Patent Publication Number: US-7595200-B2

Title: Sample processing devices and carriers

Description:
RELATED APPLICATIONS 
     This application is a continuation of Ser. No. 10/929,044, filed Aug. 27, 2004 now U.S. Pat. No. 7,445,752 which is a divisional application of U.S. Ser. No. 09/895,001, filed Jun. 28, 2001, now U.S. Pat. No. 6,814,935, which is a continuation-in-part of U.S. patent application Ser. No. 09/710,184, filed Nov. 10, 2000, now U.S. Pat. No. 6,627,159 and claims the benefit of U.S. Provisional Patent Application Ser. No. 60/214,508 filed on Jun. 28, 2000. 
    
    
     GRANT INFORMATION 
     The present invention may have been made with support from the U.S. Government under NIST Grant No. 70NANB8H4002. The U.S. Government may have certain rights in the inventions recited herein. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to the field of sample processing devices. More particularly, the present invention relates to assemblies of sample processing devices and carriers, as well as methods of using the sample processing devices. 
     BACKGROUND 
     Many different chemical, biochemical, and other reactions are sensitive to temperature variations. The reactions may be enhanced or inhibited based on the temperatures of the materials involved. In many such reactions, a temperature variation of even 1 or 2 degrees Celsius may have a significantly adverse impact on the reaction. Although it may be possible to process samples individually and obtain accurate sample-to-sample results, individual processing can be time-consuming and expensive. 
     One approach to reducing the time and cost of processing multiple samples is to use a device including multiple chambers in which different portions of one sample or different samples can be processed simultaneously. However, this approach presents several temperature control related issues. When using multiple chambers, the temperature uniformity from chamber to chamber may be difficult to control. Another problem involves the speed or rate at which temperature transitions occur when thermal processing, such as when thermal cycling. Still another problem is the overall length of time required to thermal cycle a sample(s). 
     The multiple chamber device may include a distribution system. However, the distribution system presents the potential for cross-contamination. Sample may inadvertently flow among the chambers during processing, thereby potentially adversely impacting the reaction(s) occurring in the chambers. This may be particularly significant when multiple samples are being processed. In addition, the distribution system may present problems when smaller than usual samples are available, because the distribution system is in fluid communication with all of the process chambers. As a result, it is typically not possible to prevent delivery of sample materials to all of the process chambers to adapt to the smaller volume samples. 
     Thermal processing, in and of itself, presents an issue in that the materials used in the devices may need to be robust enough to withstand repeated temperature cycles during, e.g., thermal cycling processes such as PCR. The robustness of the devices may be more important when the device uses a sealed or closed system. 
     SUMMARY OF THE INVENTION 
     The present invention provides methods and devices for thermal processing of multiple samples at the same time. The sample processing devices provide process arrays that include conduits useful in distributing sample materials to a group of process chambers located in fluid communication with the main conduits. The sample processing devices may include one or more of the following features in various combinations: deformable seals, process chambers connected to the main conduit by feeder conduits exiting the main conduit at offset locations, U-shaped loading chambers, and a combination of melt bonded and adhesively bonded areas. 
     If present in the sample processing devices of the present invention, deformable seals may provide for closure of the main conduits to prevent leakage. Deformable seals may also provide for isolation of the process chambers located along the main conduit, such that cross-contamination (e.g., migration of reagent between process chambers after introduction of sample material) between the process chambers may be reduced or eliminated, particularly during sample processing, e.g. thermal cycling. Deformable seals may also provide the opportunity to tailor the devices for specific test protocols by closing the distribution channels leading to selected process chambers before distributing sample materials. Alternatively, some deformable seals may be closed to adjust for smaller sample material volumes reducing the number of process chambers to which the sample materials are distributed. 
     Sample processing devices of the present invention that include feeder conduits connecting the process chambers to the main conduits may preferably do so using feeder conduits that exit the main conduit at different locations along the main conduit, such that no main conduit/feeder conduit junctions are directly aligned across the main conduit. Such an arrangement may provide further reductions in the possibility of cross-contamination between process chambers by providing a longer path length between the process chambers. 
     Loading structures in the form of U-shaped loading chambers, where provided, may provide advantages in filling of the loading chambers by providing a structure from which air (or any other fluid located in the loading chamber) can escape during filling. 
     Sample processing devices that include both melt bonded and adhesive bonded areas may provide the advantage of capitalizing on the properties of both attachment methods in a single device. For example, it may be preferred to use melt bonding in the areas occupied by the process chambers to take advantage of the strength of the melt bonds. In the same device, it may be possible to take advantage of the sealing properties of the adhesive bonded areas. 
     In other aspects, the sample processing devices of the present invention may be used in connection with carriers that may, in various embodiments, provide for selective compression of sample processing devices, either compression of discrete areas proximate the process chambers or compression of the sample processing devices in the areas outside of the process chambers. In various embodiments, the carriers may preferably provide for limited contact between themselves and the sample processing devices, limited contact between themselves and any compression structure used to compress the carrier and sample processing device assembly, and limited thermal mass. The carriers may also provide openings to allow visual access to the process chambers. 
     It is also preferred that the sample processing devices of the invention exhibit robustness in response to the rapid thermal changes that can be induced due to the relatively high thermal conductivity and relatively low thermal mass of the devices. This robustness may be particularly valuable when the devices are used in thermal cycling methods such as, e.g., PCR. In all thermal processing methods, the preferred devices maintain process chamber integrity despite the pressure changes associated with the temperature variations and despite the differences between thermal expansion rates of the various materials used in the devices. 
     Yet another advantage of the present invention is that the devices may be mass manufactured in a web-based manufacturing process in which the various components may be continuously formed and/or bonded, with the individual devices being separated from the continuous web. 
     As used in connection with the present invention, the following terms shall have the meanings set forth below. 
     “Deformable seal” (and variations thereof) means a seal that is permanently deformable under mechanical pressure (with or without a tool) to occlude a conduit along which the deformable seal is located. 
     “Thermal processing”(and variations thereof) means controlling (e.g., maintaining, raising, or lowering) the temperature of sample materials to obtain desired reactions. As one form of thermal processing, “thermal cycling”(and variations thereof) means sequentially changing the temperature of sample materials between two or more temperature setpoints to obtain desired reactions. Thermal cycling may involve, e.g., cycling between lower and upper temperatures, cycling between lower, upper, and at least one intermediate temperature, etc. 
     In one aspect, the present invention provides a sample processing assembly including a sample processing device and a carrier attached to the sample processing device. The sample processing device includes a body with a first side attached to a second side and a plurality of process arrays formed between the first and second sides. Each process array of the plurality of process arrays includes a loading structure, a main conduit with a length, a plurality of process chambers distributed along the main conduit, and a deformable seal located between the loading structure and the plurality of process chambers, wherein the main conduit is in fluid communication with the loading structure and the plurality of process chambers. The carrier includes a first surface facing the sample processing device and a second surface facing away from the sample processing device; a plurality of main conduit support rails proximate the first surface of the carrier, wherein each main conduit of the plurality of process arrays is aligned with one main conduit support rail of the plurality of main conduit support rails; and a plurality of openings formed through the first and second surfaces of the carrier, wherein each opening of the plurality of openings is aligned with one process chamber of the plurality of process chambers. 
     In another aspect, the present invention provides a method of processing sample materials, the method including providing a sample processing assembly that includes a sample processing device attached to a carrier. The sample processing device includes a body with a first side attached to a second side and a plurality of process arrays formed between the first and second sides. Each process array of the plurality of process arrays includes a loading structure, a main conduit with a length, and a plurality of process chambers distributed along the main conduit, wherein the main conduit is in fluid communication with the loading structure and the plurality of process chambers. Each of the process arrays also includes a deformable seal located between the loading structure and the plurality of process chambers in each process array of the plurality of process arrays. The carrier includes a first surface facing the sample processing device and a second surface facing away from the sample processing device; a plurality of main conduit support rails proximate the first surface of the carrier, wherein each main conduit of the plurality of process arrays is aligned with one main conduit support rail of the plurality of main conduit support rails; and a plurality of openings formed through the first and second surfaces of the carrier, wherein each opening of the plurality of openings is aligned with one process chamber of the plurality of process chambers. The method further includes distributing sample material to at least some of the process chambers in each process array of the plurality of process arrays through the main conduit in each of the process arrays; closing the deformable seal in each process array of the plurality of process arrays, the closing including supporting the main conduit with one of the main conduit support rails while compressing the first side and the second side of the sample processing device together along the main conduit; locating the second side of the sample processing device in contact with a thermal block; and controlling the temperature of the thermal block while the sample processing device is in contact with the thermal block. 
     In another aspect, the present invention provides a method of processing sample materials by providing a sample processing assembly including a sample processing device attached to a carrier. The sample processing device includes a body with a first side attached to a second side and a plurality of process arrays formed between the first and second sides. Each process array of the plurality of process arrays includes a loading structure, a main conduit with a length, and a plurality of process chambers distributed along the main conduit, wherein the main conduit is in fluid communication with the loading structure and the plurality of process chambers. The carrier includes a first surface facing the sample processing device and a second surface facing away from the sample processing device; and a plurality of openings formed through the first and second surfaces of the carrier, wherein each opening of the plurality of openings is aligned with one process chamber of the plurality of process chambers. The method further includes distributing sample material to at least some of the process chambers in each process array of the plurality of process arrays through the main conduit in each of the process arrays; locating the second side of the sample processing device in contact with a thermal block; selectively compressing the first side and second side of the sample processing device together proximate each process chamber of the plurality of process chambers, the selective compression occurring between the carrier and the thermal block; and controlling the temperature of the thermal block while the sample processing device is in contact with the thermal block. 
     In another aspect, the present invention provides a sample processing assembly including a sample processing device attached to a carrier. The sample processing device includes a body with a first side attached to a second side and a plurality of process arrays formed between the first and second sides. Each process array of the plurality of process arrays includes a loading structure, a main conduit with a length, and a plurality of process chambers distributed along the main conduit, wherein the main conduit is in fluid communication with the loading structure and the plurality of process chambers. The carrier includes a first surface facing the sample processing device and a second surface facing away from the sample processing device; a plurality of openings formed through the first and second surfaces of the carrier, wherein each opening of the plurality of openings is aligned with one process chamber of the plurality of process chambers; and a plurality of compression structures proximate the first surface of the carrier, each compression structure of the plurality of compression structures proximate one process chamber of the plurality of process chambers. 
     In another aspect the present invention provides a sample processing assembly that includes a sample processing device attached to a carrier. The sample processing device includes a body with a first side attached to a second side and a plurality of process arrays formed between the first and second sides. Each process array of the plurality of process arrays includes a loading structure, a main conduit with a length, and a plurality of process chambers distributed along the main conduit, wherein the main conduit is in fluid communication with the loading structure and the plurality of process chambers. Each process array also includes a deformable seal located between the loading structure and the plurality of process chambers in each process array of the plurality of process arrays. The carrier includes a first surface facing the sample processing device and a second surface facing away from the sample processing device; a plurality of main conduit support rails proximate the first surface of the carrier, wherein each main conduit of the plurality of process arrays is aligned with one main conduit support rail of the plurality of main conduit support rails; a plurality of openings formed through the first and second surfaces of the carrier, wherein each opening of the plurality of openings is aligned with one process chamber of the plurality of process chambers; and a plurality of compression structures proximate the first surface of the carrier, each compression structure of the plurality of compression structures proximate one process chamber of the plurality of process chambers. 
     In another aspect, the present invention provides a method of processing sample materials, the method including providing a sample processing assembly including a sample processing device attached to a carrier. The sample processing device includes a body with a first side attached to a second side and a plurality of process arrays formed between the first and second sides. Each process array of the plurality of process arrays includes a loading structure, a main conduit with a length, and a plurality of process chambers distributed along the main conduit, wherein the main conduit is in fluid communication with the loading structure and the plurality of process chambers. Each process array also includes a deformable seal located between the loading structure and the plurality of process chambers in each process array of the plurality of process arrays. The carrier includes a first surface facing the sample processing device and a second surface facing away from the sample processing device; a plurality of main conduit support rails proximate the first surface of the carrier, wherein each main conduit of the plurality of process arrays is aligned with one main conduit support rail of the plurality of main conduit support rails; and a plurality of openings formed through the first and second surfaces of the carrier, wherein each opening of the plurality of openings is aligned with one process chamber of the plurality of process chambers. The method further includes distributing sample material to at least some of the process chambers in each process array of the plurality of process arrays through the main conduit in each of the process arrays; closing the deformable seal in each process array of the plurality of process arrays, the closing including supporting the main conduit with one of the main conduit support rails while compressing the first side and the second side of the sample processing device together along at least a portion of the length of the main conduit; locating the second side of the sample processing device in contact with a thermal block; selectively compressing the first side and second side of the sample processing device together proximate each process chamber of the plurality of process chambers, the selective compression occurring between the carrier and the thermal block; and controlling the temperature of the thermal block while the sample processing device is in contact with the thermal block. 
     In another aspect, the present invention provides a method of processing sample materials, the method including providing a sample processing assembly including a sample processing device attached to a carrier. The sample processing device includes a body with a first side attached to a second side and a plurality of process arrays formed between the first and second sides. Each process array of the plurality of process arrays includes a loading structure, a main conduit with a length, and a plurality of process chambers distributed along the main conduit, wherein the main conduit is in fluid communication with the loading structure and the plurality of process chambers. Each of the process arrays also includes a deformable seal located between the loading structure and the plurality of process chambers in each process array of the plurality of process arrays. The carrier includes a first surface facing the sample processing device and a second surface facing away from the sample processing device; a plurality of main conduit support rails proximate the first surface of the carrier, wherein each main conduit of the plurality of process arrays is aligned with one main conduit support rail of the plurality of main conduit support rails; and a plurality of openings formed through the first and second surfaces of the carrier, wherein each opening of the plurality of openings is aligned with one process chamber of the plurality of process chambers. The method further includes distributing sample material to at least some of the process chambers in each process array of the plurality of process arrays through the main conduit in each of the process arrays; closing the deformable seal in each process array of the plurality of process arrays, the closing including supporting the main conduit with one of the main conduit support rails while compressing the first side and the second side of the sample processing device together along at least a portion of a length of the main conduit; separating the loading structure of each process array of the plurality of process arrays from the sample processing device; locating the second side of the sample processing device in contact with a thermal block; and controlling the temperature of the thermal block while the sample processing device is in contact with the thermal block. 
     In another aspect, the present invention provides a method of processing sample materials, the method including providing a sample processing assembly including a sample processing device attached to a carrier. The sample processing device includes a body with a first side attached to a second side and a plurality of process arrays formed between the first and second sides. Each process array of the plurality of process arrays includes a loading chamber, a main conduit with a length, and a plurality of process chambers distributed along the main conduit, wherein the main conduit is in fluid communication with the loading chamber and the plurality of process chambers. Each of the process arrays also includes a deformable seal located between the loading chamber and the plurality of process chambers in each process array of the plurality of process arrays. The carrier includes a first surface facing the sample processing device and a second surface facing away from the sample processing device; a plurality of main conduit support rails proximate the first surface of the carrier, wherein each main conduit of the plurality of process arrays is aligned with one main conduit support rail of the plurality of main conduit support rails; and a plurality of openings formed through the first and second surfaces of the carrier, wherein each opening of the plurality of openings is aligned with one process chamber of the plurality of process chambers. The method further includes distributing sample material to at least some of the process chambers in each process array of the plurality of process arrays through the main conduit in each of the process arrays; closing the deformable seal in each process array of the plurality of process arrays, the closing including supporting the main conduit with one of the main conduit support rails while compressing the first side and the second side of the sample processing device together along at least a portion of the length of the main conduit; separating the loading chambers of each process array of the plurality of process arrays from the sample processing device; selectively compressing the first side and second side of the sample processing device together proximate each process chamber of the plurality of process chambers, the selective compression occurring between the carrier and the thermal block; locating the second side of the sample processing device in contact with a thermal block; and controlling the temperature of the thermal block while the sample processing device is in contact with the thermal block. 
     In another aspect, the present invention provides an apparatus for closing deformable seals in a sample processing device that includes a plurality of process arrays formed between the first and second sides, wherein each process array of the plurality of process arrays includes a loading structure, a main conduit with a length, and a plurality of process chambers distributed along the main conduit, wherein the main conduit is in fluid communication with the loading structure and the plurality of process chambers, and further wherein each of the deformable seals is located between the loading structure and the plurality of process chambers in one process array of the plurality of process arrays. The apparatus includes a base with a cavity adapted to receive the sample processing device; a bridge operatively attached to the base, wherein the bridge is capable of traversing a sample processing device received in the cavity along a first direction; and a plurality of sealing structures mounted to the bridge, each of the sealing structures adapted to deform a portion of the sample processing device to close one of the deformable seals, wherein the plurality of sealing structures are aligned along the first direction such that each main conduit is sequentially deformed by the plurality of sealing structures. 
     In another aspect, the present invention provides a sample processing system including a sample processing device that includes a body with a first side attached to a second side and a plurality of process arrays formed between the first and second sides. Each process array of the plurality of process arrays includes a loading structure, a main conduit with a length, and a plurality of process chambers distributed along the main conduit, wherein the main conduit is in fluid communication with the loading structure and the plurality of process chambers. The system further includes a thermal block on which the sample processing device is located; and means for simultaneously and selectively compressing the first side and second side of the sample processing device together in a discrete area proximate each process chamber of the plurality of process chambers after locating the second side of the sample processing device in contact with a thermal block. 
     These and other features and advantages of the present invention are described below in connection with various illustrative embodiments of the devices and methods of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a plan view of one sample processing device of the invention. 
         FIG. 2  is an enlarged view of a portion of one process array on the sample processing device of  FIG. 1 . 
         FIGS. 2A &amp; 2B  depict alternative loading chambers for use in sample processing devices of the invention. 
         FIGS. 3A-3D  depict alternative arrangements of process chambers, feeder conduits and a main conduit for use in connection with the present invention. 
         FIG. 4  is a cross-sectional view of the portion of the sample processing device of  FIG. 2 , taken along line  4 - 4  in  FIG. 2 . 
         FIG. 5  is a cross-sectional view of  FIG. 4 , taken along  FIG. 5-5  in  FIG. 4 . 
         FIG. 6  is a cross-sectional view of the main conduit of  FIG. 4 , taken after deformation of the main conduit to isolate the process chambers. 
         FIG. 7  depicts an alternative sample processing device of the present invention. 
         FIG. 8  is an enlarged partial cross-sectional view of the sample processing device of  FIG. 7 , taken along line  8 - 8  in  FIG. 7 . 
         FIG. 9  depicts an alternative sample processing device of the present invention. 
         FIG. 10  is a cross-sectional view of the sample processing device of  FIG. 9 , taken along line  10 - 10  in  FIG. 9 . 
         FIG. 11  depicts an alternative sample processing device of the present invention. 
         FIG. 12  is a perspective view of a sample processing device in which the loading chambers are being separated from the remainder of the sample processing device. 
         FIG. 13  is a perspective view of the sample processing device of  FIG. 12  after sealing. 
         FIG. 14  is a plan view of another sample processing device. 
         FIG. 15  is a side view of the sample processing device of  FIG. 14  after folding the device along a line separating the loading chambers from the process chambers. 
         FIG. 16  is an exploded perspective view of an assembly including a sample processing device and a carrier. 
         FIG. 17  is a perspective view of the assembly of  FIG. 16  as assembled. 
         FIG. 18  is an enlarged view of a portion of a carrier depicting one set of main conduit support rails and collars useful in isolating the process chambers on a sample processing device of the present invention. 
         FIG. 19  is a partial cross-sectional view of a portion of a carrier illustrating one example of a force transfer structure useful within the carrier. 
         FIG. 19A  is a partial cross-sectional view of a carrier and sample processing device assembly including an optical element in the carrier. 
         FIG. 19B  depicts a carrier and sample processing device assembly including an alignment structure for a sample processing delivery device. 
         FIG. 20  is an exploded perspective view of an alternative sample processing device and carrier assembly according to the present invention. 
         FIG. 20A  is a block diagram of one thermal processing system that may be used in connection with the sample processing devices of the present invention. 
         FIG. 21  is a schematic diagram of one sealing apparatus that may be used in connection with the present invention. 
         FIG. 22  is a perspective view of the apparatus of  FIG. 21 . 
         FIGS. 23-25  depict profiles of various sealing structures used to occlude conduits in connection with the apparatus of  FIGS. 21 &amp; 22 . 
         FIGS. 26A-26F  depict various seal structures useful in connection with sample processing devices of the present invention. 
         FIGS. 27A &amp; 27B  depict one seal including an expandable material used to occlude a conduit in a sample processing device of the present invention. 
         FIGS. 28A &amp; 28B  depict an alternative construction for an sample processing device of the present invention including a core located between opposing sides. 
     
    
    
     DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS OF THE INVENTION 
     The present invention provides a sample processing device that can be used in the processing of liquid sample materials (or sample materials entrained in a liquid) in multiple process chambers to obtain desired reactions, e.g., PCR amplification, ligase chain reaction (LCR), self-sustaining sequence replication, enzyme kinetic studies, homogeneous ligand binding assays, and other chemical, biochemical, or other reactions that may, e.g., require precise and/or rapid thermal variations. More particularly, the present invention provides sample processing devices that include one or more process arrays, each of which include a loading chamber, a plurality of process chambers and a main conduit placing the process chambers in fluid communication with the loading chamber. 
     Although various constructions of illustrative embodiments are described below, sample processing devices of the present invention may be manufactured according to the principles described in U.S. Provisional Patent Application Ser. No. 60/214,508 filed on Jun. 28, 2000 and titled THERMAL PROCESSING DEVICES AND METHODS; U.S. Provisional Patent Application Ser. No. 60/214,642 filed on Jun. 28, 2000 and titled SAMPLE PROCESSING DEVICES, SYSTEMS AND METHODS; U.S. Provisional Patent Application Ser. No. 60/237,072 filed on Oct. 2, 2000 and titled SAMPLE PROCESSING DEVICES, SYSTEMS AND METHODS; and U.S. Pat. No. 6,627,159, titled CENTRIFUGAL FILLING OF SAMPLE PROCESSING DEVICES. 
     The documents identified above all disclose a variety of different constructions of sample processing devices that could be used to manufacture sample processing devices according to the principles of the present invention. For example, although many of the sample processing devices described herein are attached using adhesives (e.g., pressure sensitive adhesives), devices of the present invention could be manufactured using heat sealing or other bonding techniques. 
     One illustrative sample processing device manufactured according to the principles of the present invention is illustrated in  FIGS. 1 and 2 , where  FIG. 1  is a perspective view of one sample processing device  10  and  FIG. 2  is an enlarged plan view of a portion of the sample processing device. The sample processing device  10  includes at least one, and preferably a plurality of process arrays  20 . Each of the depicted process arrays  20  extends from proximate a first end  12  towards the second end  14  of the sample processing device  10 . 
     The process arrays  20  are depicted as being substantially parallel in their arrangement on the sample processing device  10 . Although this arrangement may be preferred, it will be understood that any arrangement of process arrays  20  that results in their substantial alignment between the first and second ends  12  and  14  of the device  10  may alternatively be preferred. 
     Alignment of the process arrays  20  may be important if the main conduits  40  of the process arrays are to be closed simultaneously as discussed in more detail below. Alignment of the process arrays  20  may also be important if sample materials are to be distributed throughout the sample processing device by rotation about an axis of rotation proximate the first end  12  of the device  10 . When so rotated, any sample material located proximate the first end  12  is driven toward the second end  14  by centrifugal forces developed during the rotation. 
     Each of the process arrays  20  includes at least one main conduit  40 , and a plurality of process chambers  50  located along each main conduit  40 . The process arrays  20  also include a loading structure in fluid communication with a main conduit  40  to facilitate delivery of sample material to the process chambers  50  through the main conduit  40 . It may be preferred that, as depicted in  FIG. 1 , each of the process arrays include only one loading structure  30  and only one main conduit  40 . 
     The loading structure  30  may be designed to mate with an external apparatus (e.g., a pipette, hollow syringe, or other fluid delivery apparatus) to receive the sample material. The loading structure  30  itself may define a volume or it may define no specific volume, but, instead, be a location at which sample material is to be introduced. For example, the loading structure may be provided in the form of a port through which a pipette or needle is to be inserted. In one embodiment, the loading structure may be, e.g., a designated location along the main conduit that is adapted to receive a pipette, syringe needle, etc. 
     The loading chamber depicted in  FIG. 1  is only one embodiment of a loading structure  30  in fluid communication with the main conduit  40 . It may be preferred that the loading chamber volume, i.e., the volume defined by the loading chamber (if so provided), be equal to or greater than the combined volume of the main conduit  40 , process chambers  50 , and feeder conduits  42  (if any). 
     The process chambers  50  are in fluid communication with the main conduit  40  through feeder conduits  42 . As a result, the loading structure  30  in each of the process arrays  20  is in fluid communication with each of the process chambers  50  located along the main conduit  40  leading to the loading structure  30 . If desired, each of the process arrays  20  may also include an optional drain chamber (not shown) located at the end of the main conduit  40  opposite the loading structure  30 . 
     If the loading structure  30  is provided in the form of a loading chamber, the loading structure  30  may include an inlet port  32  for receiving sample material into the loading structure  30 . The sample material may be delivered to inlet port  32  by any suitable technique and/or equipment. A pipette  11  is depicted in  FIG. 1 , but is only one technique for loading sample material into the loading structures  30 . The pipette  11  may be operated manually or may be part of an automated sample delivery system for loading the sample material into loading structures  30  of sample processing device  10 . 
     Each of the loading structures  30  depicted in  FIG. 1  also includes a vent port  34  with the loading structure  30 . The inlet port  32  and the vent port  34  may preferably be located at the opposite ends of the legs of a U-shaped loading chamber as depicted in  FIG. 1 . Locating the inlet port  32  and the vent port  34  at opposite ends of the legs of a U-shaped loading chamber may assist in filling of the loading structure  30  by allowing air to escape during filling of the loading structure  30 . 
     It should be understood, however, that the inlet ports and vent ports in loading structures  30  are optional. It may be preferred to provide loading structures that do not include pre-formed inlet or vent ports. In such a device, sample material may be introduced into the loading structure by piercing the chamber with, e.g., a syringe. It may be desirable to use the syringe or another device to pierce the loading structure in a one location before piercing the loading structure in a second location to fill the chamber. The first opening can then serve as a vent port to allow air (or any other gas) within the loading structure to escape during loading of the sample material. 
     Some potential alternative loading structures  30 ′ and  30 ″ are depicted in  FIGS. 2A and 2B , respectively. Loading structure  30 ′ includes an inlet port  32 ′ and a vent port  34 ′ in a generally wedge-shaped loading chamber. Loading structure  30 ″ of  FIG. 2B  also includes an inlet port  32 ″ and a vent port  34 ″ in addition to a baffle  36 ″ partially separating the loading chamber between the inlet port  32 ″ and the vent port  34 ″. The baffle  36 ″ may serve the same purpose as the separate legs of the U-shaped loading chamber depicted in  FIG. 1 . The baffle  36 ″ may take a variety of forms, for example, the baffle  36 ″ may be molded into the same side of the device as the structure of the loading chamber  30 ″, the baffle  36 ″ may be formed by attaching the sides of the device together within the loading chamber, etc. 
     Each of the process arrays  20  in the sample processing devices  10  of the present invention may preferably be unvented. As used in connection with the present invention, an “unvented” process array is a process array in which the only ports leading into the volume of the process array are located in a loading chamber of the process array. In other words, to reach the process chambers within an unvented process array, sample materials must be delivered through the loading structure. Similarly, any air or other fluid located within the process array before loading with sample material must also escape from the process array through the loading structure. In contrast, a vented process array would include at least one opening outside of the loading structure. That opening would allow for the escape of any air or other fluid located within the process array before loading during distribution of the sample material within the process array. 
     Methods of distributing sample materials by rotating a sample processing device about an axis of rotation located proximate the loading structures are described in U.S. Pat. No. 6,627,159, titled CENTRIFUGAL FILLING OF SAMPLE PROCESSING DEVICES. 
     It may be preferred that, regardless of the exact method used to deliver sample materials to the process chambers through the main conduits of sample processing devices of the present invention, the result is that substantially all of the process chambers, main conduit, and feeder conduits (if any) are filled with the sample material. 
     The process arrays  20  depicted in  FIG. 1  are arranged with the process chambers  50  located in two groups on both sides of each of the main conduits  40 . The process chambers  50  are in fluid communication with the main conduit  40  through feeder conduits  42 . It may be preferred that the process chambers  50  be generally circular in shape and that the feeder conduits  42  enter the process chambers  50  along a tangent. Such an orientation may facilitate filling of the process chambers  50 . 
     The feeder conduits  42  are preferably angled off of the main conduit  40  to form a feeder conduit angle that is the included angle formed between the feeder conduit  42  and the main conduit  40 . It may be preferred that the feeder conduit angle be less than 90 degrees, more preferably about 45 degrees or less. The feeder conduit angles formed by the feeder conduits  42  may be uniform or they may vary between the different process chambers  50 . In another alternative, the feeder conduit angles may vary between the different sides of each of the main conduits  40 . For example, the feeder conduit angles on one side of each of the main conduits  40  may be one value while the feeder conduit angles on the other side of the main conduits may be a different value. 
     Each of the feeder conduits  42  connects to the main conduit  40  at a feeder conduit junction  43 . It may be preferred that the feeder conduit junctions  43  for the different process chambers  50  be offset along the length of the main conduit such that no two feeder conduit junctions are located directly across from each other. Such a construction may enhance isolation between the process chambers  50  during thermal processing of sample materials in the different process chambers by providing a longer diffusion path length between the process chambers  50 . 
       FIGS. 3A-3D  depict a variety of different feeder conduit and process chamber arrangements that may be used in connection with the process arrays of the present invention. The variations between arrangements may be found in the shape of the process chambers, how the feeder conduits enter the process chambers, the feeder conduit angles, and whether the feeder conduit junctions with the main conduit are aligned or offset, etc. 
     Turning to  FIG. 3A , the process chambers  50   a  are connected to the main conduit  40   a  through feeder conduits  42   a . The feeder conduits  42   a  are connected to the main conduit  40   a  at feeder conduit junctions  43   a  that are located directly opposite from each other across the main conduit  40   a . In addition, the feeder conduits  42   a  enter the process chambers along a line that is not aligned with a tangent of the circular process chambers  50   a . In the depicted embodiment, the centerline of each feeder conduit  42   a  is aligned with the center of the circular process chambers  50   a , although such an arrangement is not required. 
       FIG. 3B  depicts another arrangement of process chambers and feeder conduits that is similar in many respects to the arrangement of process chambers  50   a  and feeder conduits  42   a  depicted in  FIG. 3A . One difference is that the feeder conduits  42   b  of  FIG. 3B  enter the circular process chambers  50   b  along a tangent to each of the process chambers  50   b . One potential advantage of arranging the feeder conduits along a tangent to the process chambers  50   b  may include increasing the length of the feeder conduits  42   b  (which may improve isolation of the process chambers  50   b ). Another potential advantage is that entry of liquid sample materials along a tangent to the process chamber  50   b  may enhance mixing of the sample materials with any reagents or other constituents located within the process chamber  50   b.    
     Another alternative arrangement of process chambers and feeder conduits is depicted in  FIG. 3C  where the feeder conduits  42   c  enter the process chambers  50   c  along tangents to the generally circular process chambers  50   c . One difference with the arrangement depicted in  FIG. 3B  is that the feeder conduit junctions  43   c  (the points at which the feeder conduits  42   c  connect with the main conduit  40   c ) are offset along the length of the main conduit  40   c . As discussed above, that offset of the feeder conduit junctions  43   c  may enhance process chamber isolation. 
       FIG. 3C  also depicts another optional feature in the feeder conduit angles, i.e., that included angle formed between the feeder conduits  42   c  and the main conduit  40   c . In  FIG. 3C , the feeder conduit angle α (alpha) formed on the left side of the main conduit  40   c  is different than the feeder conduit angle β (beta) formed on the right side of the main conduit  40   c . More specifically, the left-side feeder conduit angle α is less than the right-side feeder conduit angle β. The different feeder conduit angles may be useful to offset the feeder conduit junctions  43   c  when the process chambers  50   c  are located directly opposite each other across the main conduit  40   c . Potential combinations of different feeder conduit angles may be, e.g., 25 degrees on one side and 45 degrees on the opposite side, although the particular angles chosen will vary based on a variety of factors including, but not limited to, size of the process chambers, distance between the process chambers, distance between the feeder conduit junctions with the main conduit, etc. 
       FIG. 3D  depicts another arrangement of feeder conduits and process chambers that may be used within process arrays on sample processing devices according to the present invention. Although the process chambers illustrated in  FIGS. 3A-3C  are generally circular in shape, it should be understood that the process chambers used in sample processing devices of the present invention may take any suitable shape. One example of an alternative shape is depicted in  FIG. 3D  in which the process chambers  50   d  are in the form of oval shapes that are elongated along axis  51   d . The axis  51   d  is preferably generally aligned with the main conduit  40   d . As a result, the oval-shaped process chambers  50   d  have their largest dimension aligned with the main conduit  40   d.    
       FIG. 3D  also depicts feeder conduits  42   d  that are preferably angled off of the main conduit  40   d  and adjoin the process chambers  50   d  at one end. It may be further preferred that the feeder conduits  42   d  meet the process chambers  50   d  at the end closest to the loading structures (not shown). Entry of the feeder conduits  42   d  into the process chambers  50   d  at the end may facilitate removal of air within the chambers  50   d  during distribution of sample material. 
       FIGS. 4 and 5 , in conjunction with  FIG. 2 , illustrate yet another optional feature of the sample processing devices of the present invention.  FIG. 4  is a cross-sectional view of  FIG. 2  taken along line  4 - 4  in  FIG. 2  and  FIG. 5  is a cross-sectional view of  FIG. 2  taken along line  5 - 5  in  FIG. 4 . 
     It may be preferred to maintain the size of both the main conduit  40  and the feeder conduit  42  as small as possible while still allowing for adequate sample material delivery and sufficient distance between the process chambers  50  to limit diffusion. Reducing the size of the conduits  40  and  42  limits “conduit volume” within the process arrays, where conduit volume is the combined volume of the main conduit  40  and the feeder conduits  42  (where present), i.e., conduit volume does not include the volume of the process chambers  50 . It may be desirable to limit the ratio of conduit volume to the total process chamber volume (i.e., the combined volume of all of the process chambers in the subject process array) to about 2:1 or less, alternatively about 1:1 or less. 
     One manner in which conduit volume can be limited is to reduce the cross-sectional area of the main conduit  40  and/or the feeder conduits  42  (if present in the device). It may be possible to provide feeder conduits  42  with a smaller cross-sectional area than the main conduit  40  because of the reduced length of the feeder conduits  42  as compared to the main conduit  40  (making flow restriction less of a concern in the feeder conduits).  FIGS. 4 &amp; 5  depict the smaller cross-sectional area of the feeder conduit  42  as compared to the main conduit  40 . The different cross-sectional area of the conduits  40  and  42  is achieved, in the illustrated embodiment, by different heights and widths in the two conduits, although different cross-sectional areas may be achieved by varying only one of height or width in the different conduits. It may further be preferred that the height of both the main conduit  40  and feeder conduits  42  (if provided) be less than the height of the process chambers  50  as seen in  FIG. 4 . 
     It may be preferred that all of the structures forming the conduits and process chambers be provided in the first side  16  while the second side  18  is provided in the form of a generally flat sheet. In such a device, height of the conduits and process chambers can be measured above the generally flat second side  18 . 
       FIG. 4  also depicts that process chamber  50  may include a reagent  54 . It may be preferred that at least some, and preferably all, of the process chambers  50  in the devices  10  of the present invention contain at least one reagent before any sample material is distributed. The reagent  54  may be fixed within the process chamber  50  as depicted in  FIG. 4 . The reagent  54  is optional, i.e., sample processing devices  10  of the present invention may or may not include any reagents  54  in the process chambers  50 . In another variation, some of the process chambers  50  may include a reagent  54 , while others do not. In yet another variation, different process chambers  50  may contain different reagents. 
     The process chamber  50  also defines a volume  52 . In sample processing devices of the present invention, it may be preferred that the volume  52  of the process chambers be about 5 microliters or less, alternatively about 2 microliters or less, and, in yet another alternative, about 1 microliter or less. Providing sample processing devices with micro-volume process chambers may be advantageous to reduce the amount of sample material required to load the devices, reduce thermal cycling time by reducing the thermal mass of the sample materials, etc. 
     Other features of the sample processing device  10  depicted in  FIGS. 4 and 5  are a first side  16  and a second side  18 , between which the volume  52  of process chamber  50  is formed. In addition to the process chambers  50 , the main conduit  40  and the feeder conduits  42  are also formed between the first and second sides  16  and  18 . Although not depicted, the loading structures, e.g., loading structures, are also formed between the first and second sides  16  and  18  of the sample processing device  10 . 
     The major sides  16  and  18  of the device  10  may be manufactured of any suitable material or materials. Examples of suitable materials include polymeric materials (e.g., polypropylene, polyester, polycarbonate, polyethylene, etc.), metals (e.g., metal foils), etc. In one embodiment, it may be preferred to provide all of the features of the process arrays, such as the loading structures, main conduits, feeder conduits and process chambers in one side of the device, while the opposite side is provided in a generally flat sheet-like configuration. For example, it may be preferred to provide all of the features in the first side  16  in a polymeric sheet that has been molded, vacuum-formed, or otherwise processed to form the process array features. The second side  18  can then be provided as, e.g., a sheet of metal foil, polymeric material, multi-layer composite, etc. that is attached to the first side to complete formation of the process array features. It may be preferred that the materials selected for the sides of the device exhibit good water barrier properties. 
     By locating all of the features in one side of the sample processing device  10 , the need for aligning the two sides together before attaching them may be eliminated. Furthermore, providing the sample processing device  10  with a flat side may promote intimate contact with, e.g., a thermal block (such as that used in some thermal cycling equipment). In addition, by providing all of the features in one side of the sample processing device, a reduced thermal mass may be achieved for the same process chamber volume. Further, the ability to selectively compress discrete areas about each of the process chambers may be enhanced in devices in which the structure is found on only one side thereof. Alternatively, however, it will be understood that features may be formed in both sides  16  and  18  of sample processing devices according to the present invention. 
     It may be preferred that at least one of the first and second sides  16  and  18  be constructed of a material or materials that substantially transmit electromagnetic energy of selected wavelengths. For example, it may be preferred that one of the first and second sides  16  and  18  be constructed of a material that allows for visual or machine monitoring of fluorescence or color changes within the process chambers  50 . 
     It may also be preferred that at least one of the first and second sides  16  and  18  include a metallic layer, e.g., a metallic foil. If provided as a metallic foil, the side may include a passivation layer on the surfaces that face the interiors of the loading structures  30 , main conduits  40 , feeder conduits  42 , and/or process chambers  50  to prevent contamination of the sample materials by the metal. 
     As an alternative to a separate passivation layer, any adhesive layer  19  used to attached the first side  16  to the second side  18  may also serve as a passivation layer to prevent contact between the sample materials and any metallic layer in the second side  18 . The adhesive may also be beneficial in that it may be conformable. If so, the adhesive may provide enhanced occlusion by filling and/or sealing irregularities or surface roughness&#39; present on either of the two sides. 
     In the illustrative embodiment of the sample processing device depicted in  FIGS. 1 and 2 , the first side  16  is preferably manufactured of a polymeric film (e.g., polypropylene) that is formed to provide structures such as the loading structures  30 , main conduit  40 , feeder conduits  42 , and process chambers  50 . The second side  18  is preferably manufactured of a metallic foil, e.g., an aluminum or other metal foil. The metallic foil is preferably deformable as discussed in more detail below. 
     The first and second sides  16  and  18  may be attached to each other by any suitable technique or techniques, e.g., melt bonding, adhesives, combinations of melt bonding and adhesives, etc. If melt bonded, it may be preferred that both sides  16  and  18  include, e.g., polypropylene or some other melt bondable material, to facilitate melt bonding. It may, however, be preferred that the first and second sides  16  and  18  be attached using adhesive. As depicted in  FIGS. 4 and 5 , the adhesive may preferably be provided in the form of a layer of adhesive  19 . It may be preferred that the adhesive layer  19  be provided as a continuous, unbroken layer over the surface of at least one of the first and second sides  16  and  18 . It may, for example, be preferred that the adhesive layer  19  be provided on the second side  18  and, more particularly, it may be preferred that the adhesive layer  19  cover substantially all of the surface of the second side  18  facing the first side  16 . 
     A variety of adhesives may be used, although any adhesive selected should be capable of withstanding the forces generated during processing of any sample materials located in the process chambers  50 , e.g., forces developed during distribution of the sample materials, forces developed during thermal processing of the sample materials, etc. Those forces may be large where e.g., the processing involves thermal cycling as in, e.g., polymerase chain reaction and similar processes. It may also be preferred that any adhesives used in connection with the sample processing devices exhibit low fluorescence, be compatible be the processes and materials to be used in connection with sample processing devices, e.g. PCR, etc. 
     It may be preferred to use adhesives that exhibit pressure sensitive properties. Such adhesives may be more amenable to high volume production of sample processing devices since they typically do not involve the high temperature bonding processes used in melt bonding, nor do they present the handling problems inherent in use of liquid adhesives, solvent bonding, ultrasonic bonding, and the like. 
     One well known technique for identifying pressure sensitive adhesives is the Dahlquist criterion. This criterion defines a pressure sensitive adhesive as an adhesive having a 1 second creep compliance of greater than 1×10 −6  cm 2 /dyne as described in  Handbook of Pressure Sensitive Adhesive Technology  , Donatas Satas (Ed.), 2 nd  Edition, p. 172, Van Nostrand Reinhold, New York, N.Y., 1989. Alternatively, since modulus is, to a first approximation, the inverse of creep compliance, pressure sensitive adhesives may be defined as adhesives having a Young&#39;s modulus of less than 1×10 6  dynes/cm 2 . Another well known means of identifying a pressure sensitive adhesive is that it is aggressively and permanently tacky at room temperature and firmly adheres to a variety of dissimilar surfaces upon mere contact without the need of more than finger or hand pressure, and which may be removed from smooth surfaces without leaving a residue as described in  Test Methods for Pressure Sensitive Adhesive Tapes  , Pressure Sensitive Tape Council, (1996). Another suitable definition of a suitable pressure sensitive adhesive is that it preferably has a room temperature storage modulus within the area defined by the following points as plotted on a graph of modulus versus frequency at 25° C.: a range of moduli from approximately 2×10 5  to 4×10 5  dynes/cm 2  at a frequency of approximately 0.1 radian/second (0.017 Hz), and a range of moduli from approximately 2×10 6  to 8×10 6  dynes/cm 2  at a frequency of approximately 100 radians/second (17 Hz) (for example see FIG. 8-16 on p. 173 of  Handbook of Pressure Sensitive Adhesive Technology , Donatas Satas (Ed.), 2 nd  Edition, Van Nostrand Rheinhold, New York, 1989). Any of these methods of identifying a pressure sensitive adhesive may be used to identify potentially suitable pressure sensitive adhesives for use in the methods of the present invention. 
     It may be preferred that the pressure sensitive adhesives used in connection with the sample processing devices of the present invention include materials which ensure that the properties of the adhesive are not adversely affected by water. For example, the pressure sensitive adhesive will preferably not lose adhesion, lose cohesive strength, soften, swell, or opacify in response to exposure to water during sample loading and processing. Also, the pressure sensitive adhesive should not contain any components which may be extracted into water during sample processing, thus possibly compromising the device performance. 
     In view of these considerations, it may be preferred that the pressure sensitive adhesive be composed of hydrophobic materials. As such, it may be preferred that the pressure sensitive adhesive be composed of silicone materials. That is, the pressure sensitive adhesive may be selected from the class of silicone pressure sensitive adhesive materials, based on the combination of silicone polymers and tackifying resins, as described in, for example, “Silicone Pressure Sensitive Adhesives”,  Handbook of Pressure Sensitive Adhesive Technology,  3 rd  Edition, pp. 508-517. Silicone pressure sensitive adhesives are known for their hydrophobicity, their ability to withstand high temperatures, and their ability to bond to a variety of dissimilar surfaces. 
     The composition of the pressure sensitive adhesives is preferably chosen to meet the stringent requirements of the present invention. Some suitable compositions may be described in International Publication WO 00/68336 titled SILICONE ADHESIVES, ARTICLES, AND METHODS (Ko et al.). 
     Other suitable compositions may be based on the family of silicone-polyurea based pressure sensitive adhesives. Such compositions are described in U.S. Pat. No. 5,461,134 (Leir et al.); U.S. Pat. No. 6,007,914 (Joseph et al.); International Publication No. WO 96/35458 (and its related U.S. Patent application Ser. No. 08/427,788 (filed Apr. 25, 1995); U.S. Patent application Ser. No. 08/428,934 (filed Apr. 25, 1995); U.S. Patent application Ser. No. 08/588,157 (filed Jan. 17, 1996); and U.S. Patent application Ser. No. 08/588,159 (filed Jan. 17, 1996); International Publication No. WO 96/34028 (and its related U.S. Patent application Ser. No. 08/428,299 (filed Apr. 25, 1995); U.S. Patent application Ser. No. 08/428,936 (filed Apr. 25, 1995); U.S. Patent application Ser. No. 08/569,909 (filed Dec. 8, 1995); and U.S. Patent application Ser. No. 08/569,877 (filed Dec. 8, 1995)); and International Publication No. WO 96/34029 (and its related U.S. Patent application Ser. No. 08/428,735 (filed Apr. 25, 1995) and U.S. Patent application Ser. No. 08/591,205 (filed Jan. 17, 1996)). 
     Such pressure sensitive adhesives are based on the combination of silicone-polyurea polymers and tackifying agents. Tackifying agents can be chosen from within the categories of functional (reactive) and nonfunctional tackifiers as desired. The level of tackifying agent or agents can be varied as desired so as to impart the desired tackiness to the adhesive composition. For example, it may be preferred that the pressure sensitive adhesive composition be a tackified polydiorganosiloxane oligurea segmented copolymer including (a) soft polydiorganosiloxane units, hard polyisocyanate residue units, wherein the polyisocyanate residue is the polyisocyanate minus the —NCO groups, optionally, soft and/or hard organic polyamine units, wherein the residues of isocyanate units and amine units are connected by urea linkages; and (b) one or more tackifying agents (e.g., silicate resins, etc.). 
     Furthermore, the pressure sensitive layer of the sample processing devices of the present invention can be a single pressure sensitive adhesive or a combination or blend of two or more pressure sensitive adhesives. The pressure sensitive layers may result from solvent coating, screen printing, roller printing, melt extrusion coating, melt spraying, stripe coating, or laminating processes, for example. An adhesive layer can have a wide variety of thicknesses as long as it meets exhibits the above characteristics and properties. In order to achieve maximum bond fidelity and, if desired, to serve as a passivation layer, the adhesive layer should be continuous and free from pinholes or porosity. 
     Even though the sample processing devices may be manufactured with a pressure sensitive adhesive to connect the various components, e.g., sides, together, it may be preferable to increase adhesion between the components by laminating them together under elevated heat and/or pressure to ensure firm attachment of the components and sealing of the process arrays. 
     Another potential feature of the sample processing devices of the invention is a deformable seal that may be used to close the main conduit, isolate the process chambers  50 , or accomplish both closure of the main conduit and isolation of the process chambers. As used in connection with the present invention, the deformable seals may be provided in a variety of locations and/or structures incorporated into the sample processing devices. Essentially, however, the deformable seal in a process array will be located somewhere in the fluid path between the loading chamber and the plurality of process chambers. 
     With respect to  FIG. 1 , for example, the deformable seal may be located in the main conduit  40  between the loading structure  30  and the plurality of process chambers  50  of each process array  20 . In this configuration the deformable seal may extend for the substantially the entire length of the main conduit  40  or it may be limited to selected areas. For example, the deformable seal may extend along the main conduit  40  only in the areas occupied by the feeder conduits  42  leading to the process chambers  50 . In another example, the deformable seal may be a composite structure of discrete sealing points located along the main conduit  40  or within each of the feeder conduits  42 . Referring to  FIG. 7  (described below), in another configuration, the deformable seal may be limited to the area  119  between the loading structures  130  and the plurality of process chambers  150  in each of the process arrays  120 . 
     Closure of the deformable seals may involve plastic deformation of portions of one or both sides  16  and  18  to occlude the main conduits  40  and/or feeder conduits  42 . If, for example, a pressure sensitive adhesive  19  is used to attach the first and second sides  16  and  18  of the sample processing device together, that same pressure sensitive adhesive may help to maintain occlusion of the main conduits  40  and/or feeder conduits  42  by adhering the deformed first and second sides  16  and  18  together. In addition, any conformability in the adhesive  19  may allow it to conform and/or deform to more completely fill and occlude the main conduits  40  and/or feeder conduits  42 . 
     It should be understood, however, that complete sealing or occlusion of the deformed portions of the sample processing device  10  may not be required. For example, it may only be required that the deformation restrict flow, migration or diffusion through a conduit or other fluid pathway sufficiently to provide the desired isolation. As used in connection with the present invention, “occlusion” will include both partial occlusion and complete occlusion (unless otherwise explicitly specified). Furthermore, occlusion of the main conduit may be continuously over substantially all of the length of the main conduit or it may be accomplished over discrete portions or locations along the length of the main conduit. Also, closure of the deformable seal may be accomplished by occlusion of the feeder conduits alone and/or by occlusion of the feeder conduit/main conduit junctions (in place of, or in addition to, occlusion of a portion or all of the length of the main conduit). 
     In some embodiments in which the deformable seal is provided in the form of an occludable main conduit, it may be advantageous to occlude the main conduit over substantially all of its length and, in so doing, urge any sample materials within the main conduit back towards the loading chamber (e.g., as described below in connection with  FIGS. 21-25 ). It may be preferred that the sample materials urged back towards the loading chamber are driven back into the loading chamber. As a result, the loading chambers in process arrays of the present invention may also serve as waste or purge chambers for sample materials urged out of the main conduits and/or feeder conduits during closure of the deformable seals. 
     Referring now to  FIGS. 4-6 , one embodiment of a deformable seal for isolating the process chambers  50  is depicted. The deformable seal is provided in the form of a deformable second side  18  that can be deformed such that it extends into the main conduit  40  as depicted in  FIG. 6 . 
     The use of adhesive to attach the first side  16  to the second side  18  may enhance closure or occlusion of the deformable seal by adhering the two sides together within the main conduit  40 . It may be preferred that the adhesive  19  be a pressure sensitive adhesive in such an embodiment, although a hot melt adhesive may alternatively be used if deformation of the main conduit  40  is accompanied by the application of thermal energy sufficient to activate the hot melt adhesive. 
     In one method in which the process arrays  20  are closed after distribution of sample materials into process chambers  50 , it may be necessary to close the deformable seal along only a portion of the main conduit  40  or, alternatively, the entire length of the distribution channel  40 . Where only a portion of the main conduit  40  is deformed, it may be preferred to deform that portion of the main conduit  40  located between the loading chamber  30  and the process chambers  50 . 
     Sealing all of the main conduit  40  by forcing the sides  16  and  18  together along the length of the conduit  40  may provide advantages such as driving any fluid located in the main conduit  40  back into the loading structure  30 . One potential advantage, however, of sealing only a portion of the length of the main conduit  40  is that either none or only a small amount of any fluid material located in the main conduit  40  would be returned to the loading structure  30 . 
       FIGS. 7 &amp; 8  depict another sample processing device  110  according to the present invention that includes a first side  116  attached to a second side  118 , with a set of process arrays  120  formed between the two sides  116  and  118 . One difference between the sample processing device  110  depicted in  FIGS. 7 &amp; 8  and the sample processing device of  FIGS. 1 &amp; 2  is that the sides  116  and  118  of the sample processing device  110  are attached together by the combination of a melt bond and an adhesive. 
     As used herein, a “melt bond” is a bond formed by the melting and/or mixing of materials such as that occurring during, e.g., heat sealing, thermal welding, ultrasonic welding, chemical welding, solvent bonding, etc. In such a device, the materials facing each other in sides  116  and  118  must be compatible with melt bonding so that a seal of sufficient integrity can be formed to withstand the forces experienced during processing of sample materials in the process chambers. 
     The adhesive  119  is provided only within a selected area of the sample processing device and may be provided for the dual purpose of attaching portions of the two sides  116  and  118  together and assisting with sealing or occlusion of the main conduit  140  by adhering the sides  116  and  118  together as discussed above. 
     It may be preferred that the selected area of pressure sensitive adhesive  119  be located between the loading chambers  130  and the process chambers  150  as seen in  FIGS. 7 &amp; 8 . Although the pressure sensitive adhesive  119  is depicted as being limited to an area that does not include the loading chambers  130 , it should be understood that the pressure sensitive adhesive  119  may be used to attach the two sides  116  and  118  together within the area occupied by the loading chambers  130  in addition to the area between the loading structures  130  and the process chambers  150 . 
     By locating the pressure sensitive adhesive  119  in the area between the loading structures  130  and the process chambers  150 , the main conduits  140  are directed through the pressure sensitive adhesive layer  119  such that closure or occlusion of the deformable seals can be assisted by the adhesive located between the two sides  116  and  118 . Another potential advantage of attaching the two sides  116  and  118  together with a melt bond in the area occupied by the process chambers  150  is that the bond strength of the melt bond may be better suited to withstand the forces developed during thermal processing of sample materials in the process chambers  150 . 
       FIG. 7  also depicts another arrangement of process arrays  120  that may be used in connection with sample processing devices of the present invention. Each of the process arrays  120  includes a loading structure  130 . The loading structures  130  are in fluid communication with a plurality of process chambers  150  through main conduits  140 . 
     One feature illustrated in connection with  FIG. 7  is the addition of valves  144  along the main conduits  140 . By selectively opening or closing the valves  144  along the main conduit  140  (which may be either closed or open when manufactured) the delivery of sample material to each set of process chambers  150  may be enabled or prevented. For example, if one of the valves  144  is open while the other valve  144  is closed, delivery of sample material will be effected only to one set of process chambers  150  (through the open valve  144 ). 
     It may be possible to achieve the same result, i.e., enabling or preventing delivery of sample material to a subset of process chambers  150 , by sealing the main conduit  140  at an appropriate location after the bifurcation point. The use of valves  144  may, however, provided the ability for automated control or customization of the sample processing device including process arrays  120 . The valves  144  may take any suitable form, some examples of which are described in the patent applications identified above. 
     By using customizable process arrays  120 , it may be possible to provide sample processing devices that are tailored at the point of use for particular testing needs. Other advantages may be found in the ability to reduce the volume of sample material needed by reducing the number of process chambers  150  to which that sample material may be delivered. Alternatively, where a higher level of confidence is required, the valves  144  may be opened to increase the number of process chambers  150  to which sample material is delivered, thereby increasing the number of tests performed. 
       FIGS. 9 &amp; 10  depict another sample processing device  210  according to the present invention that includes a first side  216  attached to a second side  218 , with a set of process arrays  220  formed between the two sides  216  and  218 . One difference between the sample processing device  110  depicted in  FIGS. 7 &amp; 8  and the sample processing device  210  of  FIGS. 9 &amp; 10  is that the sides  216  and  218  of the sample processing device  210  are attached together by a melt bond. 
       FIG. 9  also depicts another arrangement for process arrays  220  useful in sample processing devices of the invention. Among the features depicted in connection with process arrays  220  are the staggered relationship between loading structures  230 . Such a staggered relationship may allow for a higher density of process chambers  250  on the sample processing device. 
     Each of the loading structures  230  also includes a loading port  232  and a vent port  234  which may facilitate rapid filling of the loading structures  230  by providing a pathway separate from the loading port  232  for air to escape during filling of the loading structure  230 . 
     Another feature depicted in  FIG. 9  is the serial relationship between the process chambers  250  located along each of the main conduits  240 . Each pair of successive process chambers  250  is in fluid communication with each other along main conduit  240 . As a result, if any reagents or other materials are to be located within process chambers  250  before distribution of the sample material, then some mechanism or technique for preventing removal of those materials during distribution of the sample material must be provided. For example, the reagents may be contained in a wax or other substance within each of the process chambers  250 . 
     Furthermore, it may be preferred that the height of the main conduits  240  between the process chambers  250  be less than the height of the process chambers  250 . Such a design may improve the ability to rapidly and accurately occlude the main conduits by deforming a deformable seal structure located within the main conduits  240 . 
       FIG. 11  depicts yet another arrangement of process arrays  320  on a sample processing device  310  in which the process arrays  320  share a common loading structure  330  from which a set of main conduits  340  extend. Each of the main conduits  340  connects a set of process chambers  350  to the common loading structure  330 . 
     Another feature in the process arrays  320  of sample processing device  310  are drain chambers  360  connected to the end of the main conduits  340  that is opposite the loading structure  330 . The drain chambers  360  may be separated from the main conduit by a drain valve  362  that may preferably be closed until the process chambers  350  are filled with sample material. After filling of the process chambers  350 , the drain valve  362  can be opened to allow sample material remaining in the main conduits  340  and loading structure  330  to proceed into the drain chamber  360 . The drain chambers  360  may allow for improved sealing or occlusion of the main conduits  340  by providing for the removal of sample materials from the main conduits  340  before sealing as discussed above. 
     Referring now to  FIG. 12 , another optional feature of the present invention is separation of the loading structures  430  from the remainder of another embodiment of a sample processing device  410  according to the present invention. Separation of the loading portion of the sample processing device  410  from the portion containing the process chambers  450  may provide advantages such as, for example, reducing the size of the sample processing device  410 , reducing the thermal mass of the sample processing device  410 , removing any sample materials that may remain within the loading structures  430  after distribution to process chambers  450 , etc. 
     Separation of the loading structures  430  from the sample processing device  410  may involve, for example, cutting the sample processing device  410  along the separation line  413  as depicted in  FIG. 12 . Where the loading structures  430  are to be physically separated from the remainder of the sample processing device  410 , it is typically preferable that the main conduits  440  be sealed across at least the separation line  413  to prevent leakage of the sample materials during and after the separation process. 
     The use of an adhesive within the main conduits  440  (see, e.g.,  FIGS. 2 and 3 ) may be particularly helpful to ensure adequate sealing of the main conduits  440  as discussed above. If additional sealing is required, it may also be helpful to cover the ends of the main conduits with a seal  444  as illustrated in  FIG. 13 . The seal  444  may be provided, e.g., in the form of an adhesive coated foil or other material. Alternatively or in addition to the use of an adhesive to secure the seal  444 , it may be desirable to, e.g., heat seal the seal  444  in place on the sample processing device  410 . 
     Referring now to  FIGS. 14 and 15 , one alternative to physical separation of the loading structures  530  from the remainder of the sample processing device  510  may include folding the sample processing device  510  along, e.g., separation line  513 . That folding process may also close the main conduit  540  across the separation line  513  by crimping the main conduits  540 , such that a desired level isolation may be achieved between the process chambers  550  without further deformation of any of the main conduits  540  or the feeder conduits  542 . 
     It may be desirable to provide crimping areas  546  located at the intersections of the main conduits  540  with the folding line  513  that are wider and shallower than the surrounding portions of conduits  540  to facilitate crimping of the conduits  540  during folding. The wider, shallower crimping areas  546  do, however, preferably provide a cross-sectional area for fluid flow that is similar to the cross-sectional fluid flow area of the surrounding portions of the main conduits  540 . 
     Sample processing devices may be processed alone, e.g., as depicted in  FIG. 1 . It may, however, be preferred to provide the sample processing device  610  mounted on a carrier  680 . Such an assembly is depicted in an exploded perspective view of sample processing device  610  and carrier  680  in  FIG. 16 . 
     By providing a carrier that is separate from the sample processing device, the thermal mass of the sample processing device can be minimally affected as compared to manufacturing the entire sample processing device with a thickness suitable for handling with automated equipment (e.g., robotic arms, etc.) processing in conventional equipment. Another potential advantage of a carrier is that the sample processing devices may exhibit a tendency to curl or otherwise deviate from a planar configuration. Attaching the sample processing device to a carrier can retain the sample processing device in a planar configuration for processing. 
     Carriers used in connection with the sample processing devices of the invention preferably also have some preferred physical properties. For example, it may be preferred that the carriers provide limited areas of contact with the sample processing devices to which they are mounted to reduce thermal transmission between the sample processing device and the carrier. It may further be preferred that the surface of the carrier facing away from the sample processing device also provide limited areas of contact with, e.g., a platen or other structure used to force the sample processing device against a thermal block to reduce thermal transmission between the carrier and the platen or other structure. It may further be preferred that the carriers themselves have a relatively low thermal mass to avoid influencing temperature changes in the sample processing devices. 
     Another potentially desirable physical property of carriers manufactured according to the present invention is that they exhibit some compliance such that the carrier (and attached sample processing device) can conform to the surfaces between which the assembly is compressed, e.g., a thermal block and platen. Carriers themselves may not be perfectly planar due to, e.g., variations in manufacturing tolerances, etc. Further, the assemblies may have different thicknesses due to thickness variations in the carrier and/or the sample processing device. 
     If the sample processing device  610  is to be loaded using centrifugal forces developed during rotation of the sample processing devices the centrifugal forces may challenge the sealing of the process chambers and other fluid pathways in each of the process arrays. The challenges may be especially acute when the sample processing device is constructed using an adhesive to attach to layers together. A properly designed carrier may assist in maintaining the integrity of the sample processing device by providing the opportunity to apply pressure to the card during loading and/or thermal cycling. 
     The carrier  680  may be attached to the sample processing device  610  in a manner that allows for the carrier  680  to be reused with many different sample processing devices  610 . Alternatively, each carrier  680  may be permanently attached to a single sample processing device  610  such that, after use, both the sample processing device  610  and the carrier  680  are discarded together. 
     In the depicted embodiment, the sample processing device  610  includes molded posts  611  for aligning the sample processing device  610  to the carrier. It may be preferred that at least one of the molded posts be located proximate a center of the sample processing device  610 . Although it may be possible to provide only one molded post  611  for attaching the sample processing device  610  to the carrier  680 , it may be preferred that at least two posts  611  be provided. The centrally-located post  611  may assist in centering the sample processing device  610  on the carrier  680 , while the second post  611  may prevent rotation of the sample processing device  610  relative to the carrier  680 . Further, although only two posts  611  are depicted, it will be understood that three or more posts or other sites of attachment between the sample processing devices  610  and the carriers  680  may be provided if desired. Further, the posts  611  may be melt bonded to the sample processing device  610  to also accomplish attachment of the two components in addition to alignment. 
     Posts or other alignment features may also be provided on the, e.g., the carrier  680  to generally align the sample processing device  610  on the carrier  680  before the final alignment and attachment using molded posts  611  on the sample processing device  610 . The posts or other alignment features may also assist in aligning the assembly including the sample processing device  610  and carrier  680  relative to, e.g., a thermal processing system used to thermally cycle materials in the sample process chambers  650 . Alignment may also be used in connection with a detection system for detecting the presence or absence of a selected analyte in the process chambers  650 . 
     The carrier  680  may include various features such as openings  682  that are preferably aligned with the process chambers  650  of the sample processing device  610 . By providing openings  682 , the process chambers  650  can be viewed through the carrier  680 . One alternative to providing the openings  682  is to manufacture the carrier  680  of a material (or materials) transmissive to electromagnetic radiation in the desired wavelengths. As a result, it may be possible to use a carrier  680  that is continuous over the surface of the sample processing device  610 , i.e., a carrier with no openings formed therethrough for access to the process chambers  650 . 
     The sample processing device  610  and carrier  680  are depicted attached in  FIG. 17 , where it can be seen that the loading chambers  630  may preferably extend beyond the periphery of the carrier  680 . As such, the portion of the sample processing device  610  containing the loading structures  630  may be removed from the remainder of the sample processing device  610  after distributing the sample material to the process chambers  650 . 
     The carrier  680  illustrated in  FIGS. 16 and 17  may also provide advantages in the sealing or isolation of the process chambers  650  during and/or after loading of sample materials in the process chambers  650 . 
       FIG. 18  is an enlarged view of a portion of the bottom surface of the carrier  680 , i.e., the surface of the carrier  680  that faces the sample processing device  610 . The bottom surface of the carrier  680  includes a number of features including main conduit support rails  683  that preferably extend along the length of the main conduits  640  in the associated sample processing device  610 . The support rails  683  may, for example, provide a surface against which the main conduits  640  of the sample processing device  610  may be pressed while the conduit  640  is deformed to isolate the process chambers  650  and/or seal the conduits  640  as discussed above. 
     In addition to their use during deformation of the main conduits  640 , the support rails  683  may also be relied on during, e.g., thermal processing to apply pressure to the conduits  640 . Furthermore, the use of support rails  683  also provides an additional advantage in that they provide for significantly reduced contact between the sample processing device  610  and the carrier  680  while still providing the necessary support for sealing of the main conduits  640  on device  610 . 
     The importance of reducing contact between the carrier  680  and device  610  may be particularly important when the assembly is to be used in thermal processing of sample materials (e.g., polymerase chain reaction, etc.). As such, the carrier  680  may be characterized as including a carrier body that is spaced from the sample processing device  610  between the main conduits  640  when the support rails  683  are aligned with the main conduits  640 . The voids formed between the carrier body and the sample processing device  610  may be occupied by air or by, e.g., a compressible and/or thermally insulating material. 
     Also depicted in  FIG. 18  are a number of optional compression structures  684  which, in the depicted embodiment, are in the form of collars arranged to align with the process chambers  650  on the sample processing device  610 . The collars define one end of each of the openings  682  that extend through the carrier  680  to allow access to the process chambers  650  on sample processing device  610 . The compression structures  684 , e.g., collars, are designed to compress a discrete area of the device proximate each of the process chambers  650  on the sample processing device  610  when the two components (the sample processing device  610  and the carrier  680 ) are compressed against each other. 
     That discrete areas of compression may provide advantages such as, e.g., improving contact between the device  610  and the thermal block proximate each of the process chambers. That improved contact may enhance the transfer of thermal energy into and/or out of the process chambers. Further, the improvements in thermal transmission may be balanced by only limited thermal transmission into the structure of the carrier  680  itself due, at least in part, to the limited contact area between the sample processing device  610  and the carrier  680 . 
     Another potential advantage of selectively compressing discrete areas of the device  610  is that weakening of any adhesive bond, delamination of the adhesive, and/or liquid leakage from the process chambers  650  may be reduced or prevented by the discrete areas of compression. This advantage may be particularly advantageous when using compression structures in the form of collars or other shapes that surround at least a portion of the process chambers on the sample processing device. 
     The collars in the depicted embodiment are designed to extend only partially about the perimeter of the process chambers  650  and are not designed to occlude the feeder conduit entering the process chamber  650 . Alternatively, however, collars could be provided that are designed to occlude the feeder conduits, thereby potentially further enhancing isolation between the process chambers during thermal processing of sample materials. 
     The collars  684  may optionally provide some reduction in cross-talk between process chambers  650  by providing a barrier to the transmission of electromagnetic energy (e.g., infrared to ultraviolet light) between the process chambers  650  during processing and/or interrogation of the process chambers  650 . For example, the collars  684  may be opaque to electromagnetic radiation of selected wavelengths. Alternatively, the collars  684  may merely inhibit the transmission of electromagnetic radiation of selected wavelengths by diffusion and/or absorption. For example, the collars  684  may include textured surfaces to enhance scattering, they may include materials incorporated into the body of the collar  684  and/or provided in a coating thereon that enhance absorption and/or diffusion. 
     The carrier  680  may also preferably include force transmission structures to enhance the transmission of force from the upper surface of the carrier  680  (i.e., the surface facing away from the sample processing device) to the compression structures (in the form of collars  684  in the illustrative embodiment) and, ultimately, to the sample processing device itself. 
       FIG. 19  depicts a portion of one illustrative embodiment of one force transmission structure. The force transmission structure is provided in the form of an arch  685  that includes four openings  682  and is operably attached to collars  684 . The force transmission structure defines a landing area  687  located between the openings  682  and connected to the collars  684  such that a force  686  applied to the landing area  687  in the direction of the sample processing device is transmitted to each of the collars  684 , and, thence, to the sample processing device (not shown). In the depicted embodiment, the landing areas are provided by the crowns of the arches  685 . 
     It is preferred that the arch  685  transmit the force evenly between the different collars  684  attached to the arch  685 , which are essentially provided as hollow columns supporting the arch  685  (by virtue of openings  682 ). This basic structure is repeated over the entire surface of the carrier  680  as seen in, e.g.,  FIG. 16 . 
     Advantages of providing landing areas on the force transmission structures include the corresponding reduction in contact between the carrier  680  and a platen or other structure used to compress the sample processing device using the carrier  680 . That reduced contact can provide for reduced thermal transmission between the carrier  680  and the platen or other structure used to compress the sample processing device. In addition, the force transmission structures and corresponding compression structures on the opposite side of the carrier may all contribute to reducing the amount of material in the carrier  680 , thereby reducing the thermal mass of the carrier  680  (and, in turn, the assembly of carrier  680  and sample processing device). 
       FIG. 19A  illustrates another optional feature of carriers used in connection with the present invention. The carrier  680 ′ is depicted with an optical element  688 ′, e.g., a lens, that may assist in focusing electromagnetic energy directed into the process chamber  650 ′ or emanating from the process chamber  650 ′. The optical element  688 ′ is depicted as integral with the carrier  680 ′, although it should be understood that the optical element  688 ′ may be provided as a separate article that is attached to the carrier  680 ′. 
       FIG. 19B  depicts yet another optional feature of carriers used in connection with the present invention. The carrier  680 ″ includes an alignment structure  687 ″ that may be used to assisting guiding a pipette  611 ″ or other sample material delivery device into the appropriate loading structure on the sample processing device  610 ″. The alignment structure  687 ″ may preferably be removed with the loading structures on the sample processing device  610 ″ as described herein. The alignment structure  687 ″ may be generally conical as depicted to guide the pipette  611 ″ if it is slightly off-center from an inlet port into the loading structure on sample processing device  610 ″. 
     As an alternative the molded carrier depicted in  FIGS. 16-19 , it may be possible to use a carrier in the form of a sheet of material in contact with one side of the sample processing device.  FIG. 20  is an exploded view of one illustrative sample processing device  710  and a carrier  780  that may be used in connection with the sample processing device  710 . 
     The sample processing device  710  includes a set of process arrays  720 , each of which includes process chambers  750  that, in the depicted sample processing device  710 , are arranged in an array on the surface of the sample processing device  710 . The carrier  780  includes a plurality of openings  782  formed therein that preferably align with the process chambers  750  when the sample processing device  710  and carrier  780  are compressed together. 
     The carrier  780  may be manufactured of a variety of materials, although it may be preferred that the carrier be manufactured of a compressible material, e.g., a sheet of compressible foam or other substance. In addition to compressibility, it may be preferred that the compressible material also exhibit low thermal conductivity, low thermal mass, and low compression set, particularly at the temperatures to which the sample processing device will be subjected. One class of suitable foams may include, e.g., silicone based silicone foams. 
     If the carrier  780  is manufactured of compressible material, there may be no need to provide relief on the surface of the carrier  780  facing the sample processing device  710  to prevent premature occlusion of the conduits in the process arrays  720 . If, however, the carrier  780  is manufactured of more rigid materials, it may be desirable to provide some relief in the surface of the carrier  780  for the conduits in the process arrays  720 . 
     Similar to the carrier  680  described above, a carrier  780  such as that depicted in  FIG. 20  may also provide for selective compression of the sample processing devices by not compressing the sample processing devices in the areas occupied by the process chambers  750  (due to the absence of material located above the process chambers  750 ). As a result, the carrier  780  may also provide advantages in that weakening of the adhesive bond, delamination of the adhesive, and/or liquid leakage from the process chambers  750  may be reduced or prevented by the compression provided to the sample processing device  710  outside of the process chambers  750 . In addition, thermal leakage from, e.g., a thermal block against which the assembly is urged, may be reduced if the material of the carrier  780  has desirable thermal properties (e.g., low thermal mass, low thermal conductivity, etc.). 
     The openings  782  may optionally provide some protection reduction in cross-talk between process chambers  750  by providing a barrier to the transmission of electromagnetic energy (e.g., light) between the process chambers  750  during processing and/or interrogation of the process chambers  750 . For example, the carrier  780  may be opaque to electromagnetic radiation of selected wavelengths. Alternatively, the carrier may merely inhibit the transmission of electromagnetic radiation of selected wavelengths by diffusion and/or absorption. For example, the openings  782  may include textured surfaces to enhance scattering, the carrier  780  may include materials incorporated into the body of the carrier  780  and/or provided in a coating thereon that enhance absorption and/or diffusion of selected wavelengths of electromagnetic energy. 
     The carriers described above in connection with  FIGS. 16-20  may be fixedly attached to the sample processing device or they may be separate from the sample processing device. If separate, the carriers may be removably attached to or brought into contact with each sample processing device in a manner that facilitates removal from an sample processing device without significant destruction of the carrier. As a result, such carriers may be used with more than one sample processing device. Alternatively, however, the carriers may be firmly affixed to the sample processing device, such that both components are discarded after use. In some instances, the carrier may be attached to the system used to process the sample processing devices, e.g., the platen of a thermocycling system, such that as an sample processing device is loaded for thermal processing, the carrier is placed into contact with the sample processing device. 
     Both of the carriers described above are examples of means for selectively compressing the first side and second side of a sample processing device together about each process chamber. It is preferred that the compression occur simultaneously about each process chamber. Many other equivalent structures that accomplish the function of selectively compressing the first side and second side of a sample processing device together about each process chamber may be envisioned by those of skill in the art. In some embodiments, it may be preferred that the means for selectively compressing applies compressive force over substantially all of the sample processing device outside of the process chambers (e.g., the resilient carrier  780 ). In other embodiments, it may be preferred that the means for selectively compressing applies compressive forces in only a localized area about each of the process chambers in the sample processing device (e.g., carrier  680  with its associated collars). 
     Any system incorporating a means for selectively compressing may attach the means for selectively compressing to the sample processing device or to a platen or other structure that is brought into contact with the sample processing device during processing.  FIG. 20A  depicts one thermal processing system that may be used in connection with the sample processing devices of the present invention in a block diagram format. The system includes an sample processing device  710 ′ located on a thermal block  708 ′. The temperature of the thermal block  708 ′ is preferably controlled by a thermal controller  706 ′. On the opposite side of the sample processing device  710 ′, the means for selectively compressing (in the form of carrier  780 ′) is located between the sample processing device  710 ′ and a platen  704 ′. The platen  704 ′ may be thermally controlled (if desired) by a thermal controller  702 ′ (that may, in some instances, be the same as controller  706 ′ controlling the temperature of the thermal block  708 ′). The sample processing device  710 ′ and the means for selectively compressing  780 ′ are compressed between the platen  704 ′ and thermal block  708 ′ as indicated by arrows  701 ′ and  702 ′ during thermal processing of the sample processing device  710 ′. 
       FIGS. 21-25  depict various aspects of one apparatus that may be used to isolate the process chambers in a sample processing device of the present invention, where that isolation is achieved by occluding the main conduits connecting the loading structures to the process chambers. 
       FIG. 21  is a schematic diagram of one sealing apparatus  890  that may be used in connection with the sample processing devices of the present invention. The sealing apparatus  890  is depicted with a sample processing device  810  loaded within bed  894 . The depicted sealing apparatus  890  can be used to seal or occlude the process arrays in a sample processing device  810  loaded in bed  894 . A device such as sealing apparatus  890  may be particularly useful with sample processing devices that include a set of parallel main conduits that can be sealed or occluded by deforming a portion of the sample processing devices as discussed above in various embodiments. 
     The sealing apparatus  890  includes a base  891  and a bridge  892  that is traversed across a portion of the base  891  in the direction of arrow  895 . The bridge  892  includes, in the depicted embodiment, a series of rollers  893  designed to seal or occlude portions of the process arrays by compressing the sample processing device within the bed  894 . 
     The bed  894  may be constructed of a variety of materials, although it may be preferred that the bed  894  include a layer or layers of a resilient or elastomeric material that provides some support to the sample processing devices and that can also providing some compressibility in response to the forces generated as the bridge  892  is traversed across the sample processing device  810 . 
     The bed  894  preferably includes a cavity  896  into which the sample processing device  810  is situated such that the upper surface of the sample processing device  810  is generally coplanar with the remainder of the bed  894 . The cavity  896  may be relatively simple in shape where the sample processing device  810  includes a carrier as described above. In those situations, the carrier may preferably include main conduit support rails that are located underneath each of the main conduits and support the main conduits as the rollers  893  traverse the sample processing device  810 . If no carrier is present, or if the carrier used does not include support rails for the main conduits, it may be possible to provide a shaped bed  894  that includes support rails for the portions of the sample processing device to be compressed by the rollers  893 . 
     Even if a carrier is present as a part of the sample processing device  810 , portions of the sample processing device  810  may be unsupported by the carrier, such as the portion including the loading channels (see, e.g.,  FIG. 17 ). In those situations, it may be preferred that the bed  894  include shaped portions that provide support to the main conduits outside of the carrier such that sealing or occlusion of those portions of the main conduits may be effectively performed using the apparatus  890 . 
     Sealing of the main conduits in the sample processing device  810  is accomplished by traversing the bridge  892  across the sample processing device  810  in the direction of arrow  895 . As the bridge  892  is moved, the rollers  893  rotated across the surface of the sample processing device  810  to effect the sealing of the main conduits in the sample processing device  810 . Although the sealing apparatus  890  is depicted as including a series of rollers  893 , it will be understood that the rollers could be replaced by other structural members such as pins, wires, styli, blades, etc., that, rather than rolling across the sample processing device  810 , are drawn across the sample processing device  810  in a sliding motion. It may, however, be preferred that a rolling structure be used for sealing the main conduits in sample processing device  810  to reduce the amount of friction generated during the sealing process. 
     The rollers  893  (or other sealing structures) may be mounted within the bridge  892  in a variety of manners. For example, the rollers  893  may be fixedly mounted within the bridge, such that their height relative to the base  810  is fixed. Alternatively, one or more of the rollers  893  may be mounted in a suspension apparatus such that the height of the rollers  893  can vary in response to forces generated during sealing. If suspended, the portions of the rollers responsible for sealing each of the main conduits in a sample processing device  810  may be individually suspended such that each portion of the roller can move independently of other portions of the roller. As an alternative to individually suspended portions of the rollers  893 , it may be preferred that each roller  893  depicted in  FIG. 21  be provided as a one-piece cylindrical unit with structures formed on its surface that provide the desired sealing capabilities. 
       FIGS. 23 through 25  depict enlarged partial cross-sectional views of the sealing of main conduits using a device such as sealing apparatus  890 . As depicted in the series of  FIGS. 23-25 , it may be preferred that the sealing process be accomplished with a series of rollers (or other sealing structures as discussed above) that occlude the process array conduits in a sequential manner. Referring to  FIG. 23 , for example, the roller  893   a  (only a portion of which is depicted in the cross-sectional view of  FIG. 23 ) may include a ridge  897   a  that forces/deforms a portion of the second side  818  of sample processing device  810  into the main conduit  840 . In the depicted view, the main conduit  840  includes sample material located therein. Further, the main conduit  840  is supported against the forces applied by the roller  893  by a shaped structure formed in bed  894 . If this cross-sectional view were, alternatively, taken along a line running through a carrier, the main conduit may, instead be supported by a main conduit support rail as described above in connection with the sample processing device/carrier assemblies. 
     The result of the compression is that a portion of the second side  818  and associated adhesive  819  are forced into conduit  840  (towards the first side  816 ) of the sample processing device  810 . The deformation of the second side  818  may preferably result in occlusion of the main conduit that is partial. The partial occlusion may preferably be accompanied by adhesion of the first side  816  to the second side  818  using adhesive  819  within the main conduit  840 . In some instances, this partial occlusion of the main conduit  840  may be sufficient to isolate the various process chambers located along the main conduit  840 . As a result, the view depicted in  FIG. 23  may be one of a sealed processed array in some instances. 
     It may, however, be preferred that the main conduit  840  be more occluded than that depicted in  FIG. 23 .  FIG. 24  depicts a second roller  893   b  and associated ridge  897   b  That presents a more rounded profile than the profile of ridge  897   a  depicted in  FIG. 23 . The more rounded profile of ridge  897   b  may be shaped to have a more complementary fit with the main conduit  840  of sample processing device  810 . As a result of that more complementary shape, the ridge  897   b  may preferably cause substantially complete occlusion of the main conduit  840 , thereby adhering the first side  816  together with the second side  818  within the main conduit  840 . 
     Where the second side  818  is deformed to occlude the main conduit  840  and the sample processing device is constructed using an adhesive between the first side  816  and the second side  818 , deformation of the sample processing device  810  may result in some delamination between the first side  816  and the second side  818 , particularly along the edges  898  of the main conduit  840  as depicted in  FIG. 24 . Thus, in some instances, it may be desirable to perform a secondary relamination operation after occluding the main conduits. 
       FIG. 25  depicts one mechanism that may be used to address the delamination in the form of a roller  893   c  that is designed to compress the first side  816 , second side  818 , and adhesive  819  against the bed  894  to relaminate the sample processing device along the edges  898  of the main conduit  840 . 
     The rollers or other sealing structures, e.g., pins, blades, etc., may be manufactured of a variety of materials depending on the construction of the sample processing devices to be sealed. The sealing structures may, for example, be constructed of elastomeric coated rollers or other structures, they may be coated with low surface energy materials to reduce friction, they may be constructed entirely of rigid materials (e.g., metals, rigid polymers, etc.). Further, where multiple sealing structures are used (such as the three rollers  893  depicted in  FIG. 21 ), the different sealing structures may be constructed of a variety of materials, some rigid, some resilient, some including rigid and resilient portions. For example, the roller  893   b  may preferably be constructed of rigid base roll with only the ridge  897   b  constructed of resilient material to better conform to the shape of the main conduit  840 . Alternatively, the base roll may be resilient while the ridge  897   b  is constructed of rigid materials. 
     Some Alternative Constructions 
       FIGS. 26A-26F  depict some additional optional features that may be included as a part of the deformable seal used to close the main conduits and/or the feeder conduits (if any) in sample processing devices of the present invention. One optional feature includes a seal structure  935  and a conformable seal element  936  located in area  934  of conduit  932 . It will be understood that although both features are illustrated together in  FIGS. 3A and 3B , either one may be provided alone to enhance closure of the conduit  932  in area  934 . 
     The seal structure  935  may be provided as illustrated, where it is integral with the first side  950 . Alternatively, it could be provided as an additional element attached to the substrate  152  or the adhesive  154  after it is attached to the substrate  152 . Regardless of its exact construction, it is preferred that the seal structure extend into the conduit  932  to provide a structure against which the second side  960  can be pressed to seal the distribution channel  932 . By providing a discontinuity in the otherwise preferably uniform cross-section of the conduit  932 , the seal structure  935  may enhance occlusion of the conduit  932 . Furthermore, although only one seal structure  935  is illustrated, multiple seal structures may be provided, e.g., in the form of aligned ridges. It may be preferred that the seal structure extend across the full width of the conduit  932  Additionally, the seal structure may take a variety of shapes, with the illustrated rounded ridge being only one example. Other potential shapes may include, but are not limited to, rectangular ridges, triangular ridges, etc. 
     Like the seal structure  935 , the conformable seal element  936  may be provided to enhance occlusion of the conduit  932  in the area  934  and preferably exhibits some conformance in response to the compressive forces used to occlude the conduit  932 . That conformability may improve closure of the conduit  932  after the deformation force is removed. When used with a seal structure  935  that provides a discontinuity on the opposing surface of the conduit  932 , the conformable seal element  936  may be even more effective at closing the conduit  932  as it conforms to the seal structure  935  (see  FIG. 26B ). 
     The conformable seal element  936  may be provided in a variety of forms. For example, the conformable seal element  936  may be provided as a discrete structure, e.g., an elastomer such as silicone, a conformable pressure sensitive adhesive, a wax, etc. Alternatively, the conformable seal element  936  may be provided within the various sub-layers forming the side  960  of the device  910 . In yet another alternative, the conformable seal element  936  may be provided as a thickened area of the one of the layers within the side  960 , e.g., layer  962 ,  964 , or  966 . 
       FIGS. 26C and 26D  illustrate an alternative area  934 ′ of conduit  932 ′ that includes other optional features used to close conduit  932 ′ in fluid communication with process chamber  920 ′. The area  934 ′ includes complementary mating seal structures  937 ′ and  938 ′ formed on the opposing sides  950 ′ and  960 ′ of the conduit  932 ′. When deformed during closure of the conduit  932 ′, the mating structures  937 ′ and  938 ′ may provide a more tortuous fluid path, thereby improving closure of the conduit  932 ′. 
     In yet another alternative, the seal structure  938 ′ provided on the second side  960 ′ may be provided alone, with the adhesive  954 ′ being of a uniform thickness. The adhesive  954 ′ may, however, exhibit some deformation as a result of the compressive force used to close the conduit  932 ′ and that deformation may improve occlusion of the conduit  932 ′. In addition, the adhesive  954 ′ may preferably adhere to the seal structure  938 ′, thereby further improving closure of the conduit  932 ′. 
     Yet another illustrative structure that may enhance occlusion of the conduit  932 ″ is depicted area  934 ″ in  FIGS. 26E and 26F . The structure in area  934 ″ includes a cavity  939 ″ formed in the first side  950 ″ of the device. The cavity  939 ″ may preferably include a conformable seal element  936 ″ that is forced against the opposing side of the conduit  932 ″ when the cavity  939 ″ is depressed. The conformable seal element  936 ″ may be, e.g., an elastomer, a pressure sensitive adhesive, a wax, etc. The cavity  939 ″ may preferably be dome-shaped such that pressure causes it to extend into the conduit  932 ″ as illustrated in  FIG. 26F . 
     One potential advantage of the structures in area  934 ″ is that, before closure, no portion of the structures in area  934 ″ extends into the conduit  932 ″ to impede or disrupt flow therethrough. Another potential advantage of the structures illustrated in  FIGS. 26E and 26F  is that registration of the two sides  950 ″ and  960 ″ may not be required during bonding of the two major sides because the structures are all located on one side of the device. 
     As an alternative to the structure shown in  FIGS. 26E and 26F , the conformable seal element may be provided as a layer of pressure sensitive adhesive on the second major side  960 ″ against which the cavity  939 ″ is forced upon closure of the conduit  932 ″. 
       FIGS. 27A &amp; 27B  depict yet another potential variation for the deformable seals that may be used to isolate process chambers in sample processing devices of the present invention. The depicted seal structure  1070  may be located along a conduit  1060  (e.g., main conduit or feeder conduit). The seal structure  1070  may be provided in the form of material located along the conduit  1060 . When heated above a selected temperature, the material of the seal structure  1070  deforms (in the illustrated case the deformation is in the form of expansion) to partially or completely occlude the conduit  1060 . The material used in the seal structure  1070  may be, e.g., polymer that expands to form a foamed polymer. The foaming action may be provided, e.g., by using a blowing agent or supercritical carbon dioxide impregnation. 
     Where a blowing agent is used in the seal structure  1070 , it may be impregnated into the polymer. Examples of suitable blowing agents include, but are not limited to: CELOGEN AZ (available from Uniroyal Corporation, Middlebury, Conn.), EXPANCEL microspheres (Expancel, Sweden), and glycidyl azide based polymers (available from Minnesota Mining and Manufacturing Company, St. Paul, Minn.). When the impregnated polymer is then heated above a selected temperature, the blowing agent generates a gas that causes the polymer to foam and expand and close the seal structure  1070  as depicted in  FIG. 27B . 
     Supercritical foaming may also be used to occlude the conduit  1060  by expanding the seal structure  1070 . A polymer may be caused to foam by impregnating the polymer with, e.g., carbon dioxide, when the polymer is heated above its glass transition temperature, with the impregnating occurring under high pressure. The carbon dioxide may be applied in liquid form to impregnate the polymeric matrix. The impregnated material can be fabricated into the valve structure, preferably in a compressed form. When heated the carbon dioxide expands, the structure also deforms by expanding, thereby closing the conduit  1060 . 
       FIGS. 28A and 28B  depict one alternative construction for a sample processing device  1110  according to the present invention. The sample processing device  1110  includes a core  1190 , a first side  1150  attached to one major surface of the core  1190  and a second side  1160  attached to the other major surface of the core  1190 . The second side  1160  preferably includes a metallic layer  1162  and passivation layer  1164  that is located between the metallic layer  1162  and the core  1190 . 
     The core  1190  includes a plurality of voids  1122  formed therein that extend through both major surfaces of the core  1190 . The voids  1122 , together with the first and second sides  1150  and  1160  define process chambers  1120  of the sample processing device  1110 . In addition to the voids  1122 , the process chamber volume may further be defined by structures formed in one or both of the sides. For example, the second side  1160  includes structures in the form of depressions that increase the volume of the process chambers  1120 . 
     The core  1190  may also include elongated voids  1134  that form conduits  1132  in fluid communication with the process chambers  1120 . The voids  1134  may be formed completely through the core  1190  as are the voids  1122  forming the process chambers  1120  or they may be formed only partially through the thickness of the core  1190 . 
     The core  1190  may be formed of a variety of materials, although it may be preferable to manufacture the core  1190  from polymeric materials. Examples of suitable polymeric materials include, but are not limited to, polypropylene, polyester, polycarbonate, polyethylene, etc. It may further be preferred that the core  1190  be manufactured of materials that are compatible with the reactions and any materials (samples, reagents, etc.) that may be located within the process chambers  1120 . 
     The second side  1160  may be manufactured of materials similar to those used in, e.g., the construction of the sample processing devices described above. The adhesive layers  1154  and  1164  used to connect the sides  1150  and  1160  to the core  1190  may be the same or different. As an alternative to the adhesives, the layers  1154  and/or  1164 , or their respective substrates  1152  and/or  1162 , may be constructed of materials that are amenable to melt bonding to the core  1190 . 
     Patents, patent applications, and publications disclosed herein are hereby incorporated by reference as if individually incorporated. It is to be understood that the above description is intended to be illustrative, and not restrictive. Various modifications and alterations of this invention will become apparent to those skilled in the art from the foregoing description without departing from the scope of this invention, and it should be understood that this invention is not to be unduly limited to the illustrative embodiments set forth herein.