Patent Publication Number: US-7915033-B2

Title: Incubation container system

Description:
BACKGROUND OF THE INVENTION 
     Containers for incubating living cells and tissues (e.g., Petri dishes) are employed for many types of biological experiments. Certain experiments grow cells or other biological materials on microscope slides, so that the materials can be inspected or analyzed using a microscope. The containers available for incubating living cells or tissues, however, can be inconvenient when used for slide-based experiments. 
     Slide-based biological experiments can involve placing a standard glass microscope slide bearing a biological specimen in a conventional incubation container (e.g., a Petri dish), with the slide being covered with a fluid or a reagent. The container can then be incubated for a period of time, for example so that the biological specimen on the slide can grow or otherwise change over time. After incubation, a scientist may wish to remove the microscope slide from the container to examine it using a microscope. Removing the slide from the container is difficult, however, because the slide tends to adhere to the bottom of the container. The adhesion can be attributed to the electrostatic interactions between the positive ends of the polar water molecules and the negatively charged oxygen atoms in the materials forming the glass of the container and the microscope slide. It is particularly difficult to remove a microscope slide from the container bottom when fluid is present. Furthermore, when the scientist endeavors to remove the adherent slide from the container bottom, the forces applied to the slide can cause the specimen to be disturbed, so that the accuracy of the microscopic examination is impaired. With excessive force, the microscope slide can break, with the potential for physical injury to the scientist and the potential for interfering with the overall experiment. 
     There exists a need in the art, therefore, for an incubation container conveniently sized and shaped for scientific studies that can support a microscope slide for slide-based experiments. Desirably, the microscope slide can be easily inserted into and removed from the container without disturbing any specimen that the slide supports. 
     BRIEF SUMMARY OF THE INVENTION 
     A method and system for providing a container for investigating at least one specimen are described. The method and system include providing a dish. The dish includes a floor, a plurality of sidewalls, and at least one pedestal. The floor has a perimeter. The plurality of sidewalls coupled with the floor proximate to the perimeter. The at least one pedestal resides on a portion of the floor and is pedestal configured to support at least one microscope slide distal from the floor. The microscope slide(s) bear the specimen(s) for investigation. In one aspect, the method and system also include providing a lid configured to reside on the plurality of sidewalls. 
     According to the method and system disclosed herein, the container may allow a slide to be more readily removed from the container, particularly when a fluid is desired to be present. Consequently, investigation of specimens may be facilitated. 
    
    
     
       BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS 
         FIG. 1A  illustrates the topside of an exemplary embodiment of an incubation dish. 
         FIG. 1B  illustrates the underside of an exemplary embodiment of an incubation dish. 
         FIG. 2  is a top, perspective view of another exemplary embodiment of an incubation dish 
         FIG. 3  is a top, perspective view of another exemplary embodiment of an incubation dish 
         FIG. 4A  illustrates the topside of an exemplary embodiment of a lid adapted to cover an incubation dish. 
         FIG. 4B  illustrates the underside of an exemplary embodiment of a lid adapted to cover an incubation dish. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The method and system relate to containers for biological or other material. The following description is presented to enable one of ordinary skill in the art to make and use the invention and is provided in the context of a patent application and its requirements. Various modifications to the embodiments and the generic principles and features described herein will be readily apparent to those of ordinary skill in the art. Thus, the method and system are not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features described herein. Thus, the method and system are mainly described in terms of particular systems provided in particular implementations. However, one of ordinary skill in the art will readily recognize that this method and system will operate effectively in other implementations. For example, the systems may have differing lengths, aspect ratios, sizes, or take a number of different forms, and/or be used in methodologies and experiments not inconsistent with the method and system. 
     Disclosed herein is a container for incubating biological materials that may be adapted for supporting a microscope slide and permitting the convenient placement of the slide into the container and the convenient removal of the slide from the container. Thus, the container may be used for investigating one or more specimens. The container may include a container dish and a corresponding lid. In embodiments, the incubation container may include an incubation container dish into which fluid or biological materials can be placed. A lid is configured to cover the dish, restricting evaporation of the fluids from the dish and/or preventing materials from the environment to gain access to the dish contents. In embodiments, the lid may form an airtight seal with the dish. In embodiments, the lid may form a seal with the dish that permits some air exchange or other gas flow. 
     Projecting superiorly from the base of the container dish are one or more pedestals to support at least one microscope slide. In embodiments, a single pedestal may be situated centrally in the container dish, dimensioned so that the slide balances on it. In another embodiment, the single pedestal may be configured to support the slide near the perimeter of at least part of the slide while leaving the central portion of the slide open, for example for viewing. In other embodiments, a plurality of pedestals may be situated on the base of the container dish, sized and spaced so that they support a microscope slide in a stable manner. In an embodiment, assuming that a conventional microscope slide is about three inches long and one inch wide, a pair of pedestals can be positioned, set apart from about 1.25 to 7 cm. In embodiments, the pedestals can each have a contact area of about 1 cm 2 , although other dimensions can be chosen so that a microscope slide fits comfortably but is not too loose. In other embodiments, even numbers of pedestals can be positioned to provide stable support for a slide. For example, four, six, or eight appropriately-sized pedestals can be positioned to support the slide. Odd numbers of pedestals can also be used to provide support for the slide. 
     In embodiments, the pedestals are arranged so that an inverted microscope may have an unimpeded view of the central portion of the slide. For example, the bottom of the container dish may be configured so that it provides across its entirety a viewing area, for example a viewing area of about 27 cm 2 . If a 3×1 inch slide is to be viewed, then a viewing area of at least about 12.5 cm 2  may be used so that the slide can be accessed by an inverted microscope if a pair of pedestals are positioned, for example, about 5 cm apart. Pedestals may be shaped as squares, rectangles, circles, ovals, pyramids or any other shape that can support the microscope slide in a stable manner. When a plurality of pedestals is employed, the pedestals can be positioned in any pattern that allows support of the slide along with microscopic access thereto. In embodiments, the pedestals are positioned so that a technician can readily manipulate the microscope slide digitally or with an instrument. 
     The pedestals may be formed integrally with the incubation container dish, or the pedestals may be attached to the incubation container dish. If the pedestals are formed integrally with the incubation container, they may be formed from plastic materials by injection molding or milling, and the like. In embodiments, the pedestals may be made of plastic, glass, rubber, metal or ceramic, and affixed to the floor of the dish. In some embodiments, plastic, glass and rubber would be used for biological applications. If the pedestals are attached to the incubation container, they may be attached using glues or epoxies, or the like. Other methods of forming incubation containers with pedestals may also be used. 
     The pedestals may be dimensioned to support the microscope slide sufficiently close to the bottom of the incubation container dish that an inverted microscope can be used to examine a specimen placed upon the slide. In embodiments, the pedestals are about 4 mm in height, measured from the lowest point on the bottom of the dish to the top surface that would support the slide. Other heights for the pedestals can be designed to account for differences in the type of microscope used, for example, the focal length of the objective lens. For example, taller pedestals may be suitable for applications where lower magnifications and/or longer working distances would be used. In one embodiment, the pedestal height of about 4 mm is selected to permit the ready observation of cells through the bottom of the dish using the 10×objective of an inverted microscope, while also permitting ready manipulation of the slide by a scientist. 
     In embodiments, the container dish and lid may be made from a variety of materials, depending on the circumstances of its use. For containers where an inverted microscope will be used to inspect the microscope slide that the container bears, the container dish is desirably made from an optically clear material, for example, an optically clear polycarbonate. The dish can be made of a homogeneous material, or it can have specific areas with particular properties. For example, a container dish can embed a lens or a filter in its substance, to permit particular microscopic techniques. In other embodiments, the container dish can be made of other materials, for example, glasses, metals, resins, plastics, ceramics, clay, and the like. In some embodiments, the container dish and lid may be made of different materials, while in other embodiments, the container dish and lid may be made of the same material(s). 
     For certain biological applications, it is desirable to use a material for the container dish that can withstand exposure to a number of reagents, that has a low degassing value, and that is optically clear. While certain container dishes can, in embodiments, be designed to be disposable after a single use, in other embodiments, it is advantageous to fabricate a container dish that can be used multiple times. Polycarbonate is particularly suitable for biological applications, because it can withstand the conditions in an autoclave, as would be used for sterilizing biological instruments. 
       FIG. 1A  shows a top, perspective view of an exemplary embodiment of an incubation container dish  102  having a sidewall  104  joining a floor  108 . In the depicted embodiment, the sidewall  104  joins the floor  108  through a series of beveled edges  110  that smooth the juncture of sidewall  104  to floor  108 . In other embodiments, the sidewall  104  forming a vertical boundary for the incubation dish  102  can join the floor  108  at any angle or as a rounded juncture. Other optional features of the floor  108  can be envisioned, such as a moat (not shown) to hold fluid in a trough surrounding the periphery of the floor  108 , or a system of one or more pools (not shown) that contain fluids or reagents situated at specific locations on the floor  108 , and formed as depressions in the floor  108 . For floors  108  having such optional features, the height of the floor  108  can be elevated so that the moat (not shown) or the pools (not shown) do not project below the bottom of the overall incubation dish  102 . The floor  108  is desirably made from an optically clear material so that a microscope imaging system placed under the dish  102  can image a microscope slide (not shown) that is supported by the plurality of pedestals  114  that are formed within the dish  102 . In the embodiment shown, the pedestals  114  are configured to support one microscope slide. However, in another embodiment, the pedestals  114  may be configured to support multiple slides. In addition, in some embodiments, the pedestals  114  are configured to support the microscope slide(s) at a distance from the floor  108  that is less than the height of the sidewalls  104 . Thus, the microscope slide(s) may be retained between the floor  108  and a lid (not shown in  FIG. 1A ). The depicted embodiment shows the sidewalls  104  of the incubation dish  102  joining to form rounded corners  116 , but in other embodiments, the corners  116  can meet at right angles, or can be formed from several angled panels, or in any other suitable shape. The incubation dish  102  may be sized and shaped to conform to the user&#39;s requirements. In an embodiment, it can measure about 4.6 inches in length and 2.6 inches in width, with sidewalls  104  measuring about 0.5 inches in height 
       FIG. 1A  shows, in more detail, a plurality of pedestals  114  projecting from the floor  108 . In the depicted embodiment, the floor  108  and the sidewall  104  form boundaries in which fluid can be retained. The pedestals each have surfaces  118  that can support a microscope slide (not shown). In one embodiment, the surfaced  118  may be flat. In another embodiment, the surfaces  118  may have another topology capable of supporting a microscope slide. The depicted embodiment of an incubation dish  102  shows a set of ridges  120  on the flat surfaces  118  of the pedestals  114  that can hold the microscope slide in place. The height of the pedestals  114  relative to the floor  108  is such that a technician can conveniently position the microscope slide on the pedestals  114  or remove it therefrom. For example, the pedestals  114  can project about 0.16 inches from the floor  108 ; other projection amounts can be designed to meet individual user needs. Ridges  120  can be sized proportionately to the dimensions of the pedestals  114  and the incubation dish  102  so that the dish  102  can be covered by a lid (not shown) without the lid impinging upon the ridges  120 . In the depicted embodiment, the height of the sidewall  104  exceeds the height of the pedestals  114  so that the microscope slide supported on the pedestals  114  can be immersed in a fluid if desired. On the external aspect of the incubation dish  102  is an outside rim  122  upon which a cover (not shown) for the incubation dish can rest. 
       FIG. 1B  shows an exemplary embodiment of an incubation dish  102  shown from the underside. Rising from the floor  108  are two pedestals  114 . In another embodiment, the pedestals  114  may not change the topology of the underside. In the depicted embodiment, the pedestals  114  are formed in continuity with the rest of the dish  102 . In other embodiments, the pedestals  114  may be attached as separate structures to the floor  108  of the dish  102 . The floor  108  is desirably formed from an optically clear material to permit imaging through it. In the depicted embodiment, the sidewall  104  joins the floor  108  through a series of beveled edges  110  that smooth the juncture of sidewall  104  to floor  108 . 
       FIG. 2  shows a top, perspective view of another exemplary embodiment of an incubation container dish  102 ′. The container dish  102 ′ is analogous to the container dish  102 . Consequently, analogous components have similar labels. Thus, the container  102 ′ includes sidewalls  104 ′, floor  108 ′, beveled edges  110 ′, pedestals  114 ′, corners  116 ′, surfaces  118 ′, ridges  120 ′, and rim  122 ′, In addition, the container dish  102 ′ includes moat  126  which may be used to hold fluid. The moat  126  is depicted as residing at the periphery of the floor  108 ′ but between the pedestals  114 ′. However, in another embodiment, the moat  126  may extend at the periphery of the floor  108 ′, having the pedestals  114 ′ interior to the moat  126 . In addition, although a single moat  126  is depicted, the container dish  102  may include multiple moats. Further, the moat  126  is depicted as being formed within the floor  108 ′. However, in another embodiment, the moat  126  may be formed by raised walls. In such an embodiment, a portion of the floor  108 ′ may serve as the bottom of the moat  126 . 
       FIG. 3  shows a top, perspective view of another exemplary embodiment of an incubation container dish  102 ″. The container dish  102 ″ is analogous to the container dish  102 . Consequently, analogous components have similar labels. Thus, the container  102 ″ includes sidewalls  104 ″, floor  108 ″, beveled edges  110 ″, pedestals  114 ″, corners  116 ″, surfaces  118 ″, ridges  120 ″, and rim  122 ″, In addition, the container dish  102 ″ includes pools  128  which may be used to hold fluid. The pools  128  are depicted as residing between the pedestals  114 ″. However, in another embodiment, the pools  128  may extend to and/or reside at the periphery of the floor  108 ″, closer to the sidewalls  104 ″ than the pedestals  114 ″. Further, the pools  128  are depicted as being formed within the floor  108 ″. However, in another embodiment, the pools  128  may be formed by raised walls. In such an embodiment, a portion of the floor  108 ″ may serve as the bottoms of the pools  128 . 
       FIG. 4A  shows a top view of an embodiment of a lid  202  adapted for use with an incubation dish such as can be seen in  FIGS. 1A ,  1 B,  2 , and  3 . In the depicted embodiment, the lid  202  has a flat, optically clear top surface  204 . In other embodiments, a non-flat surface can be used for the lid  202 , and the lid  202  can be used with materials having other optical properties such as a degree of opacity to prevent light from entering the underlying incubation dish, or optically frosted to cut down light exposure. In the depicted embodiment, the lid wall  208  is optically clear as well, although it may be envisioned that the lid wall  208  may be made from materials having other optical properties. Extending vertically downward from the horizontal top surface is a circumferentially disposed lid rim  214 , configured to overlap with the sidewalls of an underlying incubation dish (not shown). In an embodiment, the lid  202  can measure about 4.6 inches in length and 2.6 inches in width, corresponding to the dimensions of an underlying incubation dish (not shown), with a lid wall  208  measuring about 0.26 inches in height. The lid rim  214  may bear indentations, projections, or other texturing features (not shown) that facilitate its manipulation. In the depicted embodiment, the corners  210  of the lid are curved, conforming to the shape of the incubation dish as depicted in  FIGS. 1A ,  1 B,  2 , and  3 . It is understood that the corners  216  desirably conform in shape to the corners of the underlying incubation dish. As shown in  FIG. 4B , a plurality of notches  212  may be disposed along the inner aspect of the lid rim  214  to elevate the lid  202  off the underlying incubation dish, thereby allowing an air gap for gas exchange. Without the notches  212 , the lid  202  can rest on the top of the incubation dish, providing a relatively gas-tight seal. Optionally, a gasket (not shown) can be provided to produce a more complete gas-tight seal. In another embodiment, the rim  214  may snugly fit the sidewalls of an incubation dish, such as the incubation dish  102 . In such an embodiment, once closed the combination of the lid  202  and container dish  102  may retain fluid and/or gas therein. 
     While the container has been described in connection with certain embodiments, other embodiments would be understood by one of ordinary skill in the art and are encompassed herein. It will be understood that various changes and modifications can be made all within the full and intended scope of the following claims. Accordingly, many modifications may be made by one of ordinary skill in the art without departing from the spirit and scope of the appended claims.