Abstract:
A saliva sampling device includes an expresser cup, an absorbent foam swab capable of absorbing a fluid specimen, and a flexible tether affixed to the foam swab. The foam swab is used to collect a sample of a fluid specimen such as saliva, and the tether is adapted to enable a user to sanitarily draw the saturated foam swab into the expresser cup in which the foam swab becomes compressed: and the absorbed fluid is expressed therefrom in a drop by drop fashion. The device also may include a platform having a reagent strip for absorbing the expressed fluid to reveal test results. The device may also include a divider for separating the expressed fluid into two or more aliquots prior to the testing thereof such that one of the aliquots may be used for confirmation or later testing of the fluid. In one embodiment, the expresser cup includes a conical cross section to effect gradual compression of the foam swab.

Description:
The present invention generally relates to fluid specimen collection devices, and more specifically relates to a saliva sampling device and method for extracting saliva for use in diagnostic tests. 
     Unlike other forms of fluid specimens such as blood or urine, collection of oral fluid, such as saliva, for diagnostic purposes is complicated by many factors, for example, the low volumes of salivary fluid secreted, the relatively high viscosity of the fluid, and the diverse anatomic dispersion of the salivary glands. These problems become compounded when a single saliva sample is to be divided into two or more portions as is sometimes desired. Most techniques for collection involve the use of capillary tubes, suction into micro pipettes, chewing on paraffin, and/or aspiration from the mouth into polypropylene syringes. 
     In addition, testing of salivary specimens has not yet been extensively developed. Blood and urine samples have for long been the primary fluids used for testing for disease as well as for evidence of substance abuse. However, it is now known that human saliva carries lymphocytes, plasma cells and immunoglobulins that are directly related to the immunoglobulins found in the blood. In addition, saliva carries immunoglobins that are believed to be peculiar to saliva, for example, the antibody known as secretory IgA. Because of the association between immunoglobulins of the blood and saliva, as well as the occurrence of secretory IgA, antigen-antibody tests have been conducted on salivary fluid to assess the value of such tests as screening tools for disease. 
     U.S. Pat. No. 5,922,614 to Cesarczyk describes a Sample Collection Method with Extraction Sleeve. The device is designed for collecting saliva or urine samples using an absorbent, elongate foam member secured within a hollow tube and having a portion extending therefrom. The foam member is used to absorb a fluid specimen. The foam member and hollow tube are slidably mounted within an outer sleeve covering the foam member. Fluid is collected by a user exerting pressure against the sleeve to compress the foam member and thereby release the fluid. According to Cesarczyk, the device provides an aseptic, easy to use device for collecting a fluid sample such as saliva. 
     The present invention exemplifies an improved oral fluid collection device which is easier to use than other devices in the field that are those presently available. 
     The present invention provides an improved sampling device for collecting and delivering an oral fluid specimen such as saliva, for diagnostic testing. 
     SUMMARY OF THE INVENTION 
     Accordingly, a method and device are provided for both collecting and delivering a fluid sample, such as blood, urine or saliva for diagnostic testing. It is noted that the device is especially advantageous for samples of which only a low volume of sample is available for collection, specifically saliva. 
     The device generally comprises an expresser, having a distal open end connected to a port, and a generally closed proximal end. The expresser is adapted to receive an absorbent member substantially saturated with a fluid specimen, through the distal opening. As the absorbent member is pulled through the distal opening and into the port, the port provides means for compressing the absorbent member to effect expression of the fluid specimen therefrom the absorbent member. 
     Connected to the expresser distal open end is a platform for collecting at least a portion of the specimen as it is expressed from the absorbent member. The platform preferably is adapted to provide means for testing the fluid specimen. For example, the platform may include a sample well for receiving drops of expressed fluid. To facilitate flow of the expressed fluid into the sample well, the expresser may be disposed at an angle with respect to the generally horizontal platform. 
     The sample well may include a first port and a second port, comprising, for example a test port and a confirmation port respectively. In addition, the platform may include a lateral flow test strip in fluid communication with the test port, and a confirmation container in fluid communication with the confirmation port. Preferably, the platform has a closed top surface encasing the test strip, and a viewing window exposing a portion of the strip. 
     In one especially advantageous embodiment, the device further comprises means for dividing the fluid expressed from the expresser. For example, a partition, disposed between the test and confirmation ports and extending at least partially into the expresser container is provided. A ratio of confirmation sample to lateral flow sample could be adjusted by changing location and/or configuration of the dividing partition. 
     In one embodiment of the invention, an absorbent member is provided, as well as tether means for enabling manual handling of the absorbent member. The expresser distal opening may include an inlet, sized for passage of the absorbent member, and a longitudinal slot in communication with the inlet, sized for passage of the tether means. By controlling the pulling of the tether, the user may cleanly and controllably express the fluid, drop by drop, to be used for testing/diagnostic purposes. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The objects and advantages of the present invention: will be more clearly understood and appreciated with reference to the following detailed description when considered in conjunction with the appended drawings of which: 
     FIG. 1 shows a perspective view of a saliva sampling device in accordance with the present invention, including an expresser adapted to receive an absorbent member, the expresser including a port adapted to compress the absorbent member to effect expression of saliva fluid absorbed by the absorbent member, and collection means, comprising a platform connected to the expresser, for collecting the portion of fluid for testing; 
     FIG. 2 shows a top view of the device in FIG. 1; 
     FIG. 3 shows a cross sectional view of the device taken along line  3 — 3  of FIG. 2; 
     FIG. 4 shows a cross sectional view of the device taken along line  4 — 4  of FIG. 2; 
     FIG. 5 shows a side view of an absorbent member and tether combination suitable for use in the device shown in FIGS. 1-4; 
     FIG. 6 shows a confirmation container useful in the device of the present invention for storing a portion of the expressed saliva fluid for processing at a later time; and 
     FIG. 7 shows an expresser cup useful with a method of the present invention. 
    
    
     DETAILED DESCRIPTION 
     Turning now to FIGS. 1-4, an embodiment of the fluid specimen sampling device  10  in accordance with the invention is shown. The device  10  generally comprises a substantially cylindrical member, hereinafter referred to as an “expresser”  12  for reasons which will later become apparent. The expresser  12  includes a proximal, generally closed end  14  and a distal, substantially open end  16 . The expresser  12  is adapted to receive an absorbent member  17  (not in view in FIG. 2) through the distal open end  16 , said absorbent member  17  to be described in greater detail hereinafter. In accordance with a method of the present invention, a fluid specimen or sample is applied to the absorbent member  17  and is expressed therefrom for collection and testing. For example, the absorbent member  17  may comprise an absorbent sponge, foam swab or like material capable of absorbing a fluid specimen such as saliva, sized to be comfortably placed in a mouth of a patient or subject person (not shown). After the foam swab  17  is so placed in the mouth, it is allowed to remain in the mouth for a sufficient time to allow a sample of saliva fluid to be absorbed thereby. The time for absorption of a sufficient amount of specimen will generally vary depending upon the particular subject person. 
     The expresser  12  is designed to enable sanitary, effective expression of at least a portion of the fluid sample that has been absorbed by the foam swab  17  in an amount sufficient for testing and/or collection. Referring specifically now to FIGS. 3 and 4, the expresser  12  includes a port  20 , defined by inner walls  22  thereof, the port terminating at the proximal end  14 . The expresser port  20  provides means for compressing the foam swab  17  as the foam swab  17  is passed into the expresser  12 . A tether  24 , connected to the absorbent member  17  is provided for enabling a user to pull the absorbent member  17  into the port  20 . 
     As shown in FIGS. 3 and 5 the tether  24  may comprise a flexible, plastic monofilament having a distal portion  30  passing through the absorbent member  17  with a hook  32  outside of the absorbent member  17 , thereby providing a simple, yet secure engagement therebetween. A handle  34  (shown only in FIG. 5) is provided for facilitating manual handling of the foam swab  17 . 
     Referring back now to FIGS. 1-3, the device  10  further comprises means for collecting the expressed fluid sample. Specifically, for example, a platform  48  having a sample well  50  in communication with the expresser distal opening  16  may be provided wherein the platform  48  includes a plastic housing  52  supported by legs  54 , skirt (not shown) or other suitable structure. The housing  52  is structured to accommodate at least one reagent strip or one lateral flow test strip  58  made of nitrocellulose or other suitable material, said lateral flow test strip  58  having a portion  60  being exposed to the sample well  50 . Reagent strip  58  will not be further described in detail herein, as lateral flow test strips suitable for use with the present invention are well known in the art of diagnostic testing devices. 
     Preferably, as shown most clearly in FIGS. 1 and 4, in order to effectively channel the flow of expressed fluid into the sample well  50 , the expresser  12  is connected to the platform  48  at an inclined angle, for example, of about 45 degrees. 
     Upon deposit of the expressed sample fluid into the sample well  50 , the fluid begins migration along the test strip  58 . A window  60  in the platform  48  provides means for enabling viewing of a test strip portion  62  that reveals validity, positive/negative or quantitative test results. 
     In one especially advantageous aspect of the invention, the sample well  50  may be divided into two or more sub-ports, for example, a first port  72  and a second port  74 . The first port  72  and second port  74  will be hereinafter designated as a test port and a confirmation port, respectively, although it is contemplated that the ports may both function as different test ports, for example. As shown in FIG. 3, the test port  72  is in fluid communication with the lateral flow test strip  58  such that a first portion of the fluid, deposited in the test port  72 , will immediately begin migration along the strip  58 . Similarly, the confirmation port  74  may be in fluid communication with a confirmation container  78  for collecting and/or storing a second portion of the fluid for confirmation of patient identity, test validity or other processing steps to be performed at a later time. 
     Referring to FIGS. 1,  3  and  4 , the confirmation container  78  is shown depending from the platform  48  immediately beneath the confirmation port  74 . Preferably, as shown in FIG. 4, suitable means, for example cooperating plug  80  depending from the platform, is provided for removably coupling the container  78  to the platform  48 . Turning to FIG. 6, additionally provided is a tamper evident closure cap  81  for sealing the confirmation container  78  after it has been removed from the platform  48 . 
     Turning again to FIGS. 1-4, means for dividing the sample fluid is provided. More specifically, a partition  82 , extending substantially normal to the platform  48  and at least partially into the expresser  12  is provided for dividing the fluid sample into two or more portions as the fluid is being expressed and collected. The partition  82  is secured to the platform  48  within the sample well  50  and may be substantially flush with the inner wall  22  defining the expresser port  20  (see FIGS.  3  and  4 ). As shown in FIG. 3, the partition  82  functions to direct a portion of the expressed fluid into the test port  72  (flow portion represented by arrow  88 ) and another portion of the expressed fluid into the confirmation port  74  (flow represented by arrow  89 ). This feature of the invention enables a user to divide and perform multiple tests or procedures on an individual sample of a fluid, such as saliva which is typically difficult to collect in any substantial quantity. 
     It is contemplated that an alternative feature of the invention includes manually squeezable walls of the expresser  12 , provided as an alternative or additional means for expressing fluid from the foam swab  17 . More specifically, after the absorbent member  17  is pulled into the expresser  12 , drops of the fluid may be extracted therefrom by the user manually applying pressure to, or squeezing, the expresser  12 . A suitable material for the squeezable expresser is a low density polyethylene plastic. 
     Referring back now to FIGS. 1 and 2, the device  10  may further comprise means  96  for facilitating insertion of the absorbent member  17  and tether  24  into the expresser  12 . Particularly, the expresser  12  may include a wide inlet  98  sized for substantially uncompressed passage of the absorbent member  17 , and a longitudinal slot  102  in communication with the distal end inlet, sized for passage of the tether  24 . As shown in FIG. 2, the slot  102  extends from the wide inlet  98  through the proximal end  14  of the expresser  12 . 
     The device  10  may further include means for holding the absorbent member  17  in a compressed position to enable a user to manually release the tether after the absorbent member  17  has been compressed without causing the absorbent member  17  to expand and potentially reabsorb the expressed fluid. The user may therefor attend to other tasks while waiting for the absorbed fluid to be expressed from the foam swab  17  and flow along the expresser inner walls  22 . It noted that this feature is especially advantageous for use with high viscosity, cohesive fluids such as saliva which tend to flow relatively slowly. 
     Collecting and testing of a fluid specimen may be performed as follows. The absorbent foam  17 , having the tether  24  secured thereto, is placed in the mouth of a patient, or subject person, and the foam  17  is kept in the mouth until it is substantially saturated with saliva fluid. A technician, or other user of the device  10  can thereafter sanitarily handle the absorbent member  17  by means of the handle  34 . The technician places the saturated foam  17  into the wide inlet portion  98  of the slot means  96  and the tether  24  is gently pulled toward and into the slot  102  such that it eventually projects from the expresser  12  through the proximal end  14  thereof. 
     To express the absorbed fluid from the foam  17 , the technician gently pulls the tether handle  34  to cause the foam  17  to enter the port  20  and become compressed thereby and eventually be squeezed within the expresser port  20 . 
     A small disk  36 , or the like, made for example of rubber or plastic, may be slidably engaged to the tether  24  such that the fluid specimen will be substantially prevented from leaking from the expresser  12  during the compression of the swab. 
     Expressed fluid is channeled toward the sample well  50  and divided by the partition  82 . Means, such as a narrow end  104  of the slot  102 , may be provided for locking the tether  24 , thereby holding the foam  17  in a compressed position, such that the expressed fluid will not inadvertently be reabsorbed by the foam swab  17 . A portion of the fluid is collected in the confirmation container  78  which is may then removed from the platform and sealed with cap  81 . The technician may read test results through window  60 . 
     Preferably, the device is configured on such a way that the reagent strip may be successfully photocopied or scanned to preserve a copy of the test results. For example the device  10  may structured such that the expresser is easily removable from the platform lowering the profile of the test device  10 . 
     Turning now to FIG. 7, the alternative saliva sampling device  110 , comprising conical expresser  112 , hereinafter referred to as “expresser cup”  112 , is shown, with like parts being represented by like reference numerals. This device  110  is useful for collecting and testing an oral fluid sample, in accordance with a method the invention, and may be used independently and exclusively of the platform  48 . For example, the device  110  may be used to provide a particular number of drops of an absorbed fluid sample, to be deposited onto conventional fluid specimen testing apparatus or into collection canisters (not shown). 
     In this embodiment, the tether foam  17  is threaded through the expresser cup  112 , without the expresser cup  112  being secured to the platform  48  of FIGS. 1-4. The assembled device  10  is then used in sampling with a proximal end  124  of the cup  112  located next to the tether handle  34 . After the foam  17  is saturated the fluid specimen, the foam  17  is removed from the mouth and, with one hand of a user holding the expresser cup  92 , and another hand holding the handle  34 , the foam is gently pulled into the cup  122 , causing the foam  17  to enter the narrowing expresser cup  92  until a desired number of drops of the oral fluid is expressed therefrom. An open distal end  122  of the cup  112  may be placed over a collection area whereon the expressed fluid may be dropped for immediate testing or collection for later confirmation or use thereof. In this example, a slot such as  96 , is preferably not provided. Assembly of the device  110  may be accomplished by threading the tether  24  through a proximal end opening  125 , and subsequently attaching the absorbent member  17  to the tether  24  using suitable means. 
     In another aspect of the invention, individual drops of fluid may be obtained by carefully controlling manual pulling of the absorbent member into the expresser  120 . As an example, a first drop of fluid may be obtained by pulling the absorbent member  17  into the expresser cup  112  and allowing the absorbent member  17  to be sufficiently compressed thereby to cause expression of only a single first drop of fluid. The first drop is thereafter collected onto a collection area. One or more additional drops of the fluid sample may be obtained by continuing to pull the absorbent member  17  further into the port and allowing the additional drops to flow and drop from the expresser cup  122 . These additional drops may be deposited onto the same collection area or onto a different collection area (for example, into a standalone confirmation canister) by simply positioning the expresser  122  over the desired collection area. The above steps may be repeated until the desired number of drops are obtained and collected. The method may further comprise separately processing the drops of fluid. For example, the step of separately processing may comprise directing a first drop: onto a lateral flow test strip for testing, and storing a second drop in a canister or container for use in confirmation testing or otherwise processing at a later time. 
     It is to be appreciated that although the present devices  10 ,  120  were developed for use in the collecting and testing of oral fluid, for example saliva, with appropriate modification thereto, the devices  10 ,  120  may be adapted for the collection and testing of blood, plasma, serum, urine or other fluid specimens. For example, the absorbent member  17  may be made of materials presently known to those skilled in the art, to be suitable for the absorption of said other fluid specimens. 
     Although there has been hereinabove described a saliva sampling device, in accordance with the present invention, for the purpose of illustrating the manner in which the invention may be used to advantage, it will be appreciated that the invention is not limited thereto. Accordingly, any and all modifications, variations, or equivalent arrangements which may occur to those skilled in the art should be considered to be within the scope of the invention as defined in the appended claims.