WO2001089963A1

WO2001089963A1 - Test tube rack assembly having a common liquid-tight tube seal

Info

Publication number: WO2001089963A1
Application number: PCT/US2001/016361
Authority: WO
Inventors: Carl Ted Edens
Original assignee: Digene Corporation
Priority date: 2000-05-19
Filing date: 2001-05-18
Publication date: 2001-11-29

Abstract

A test tube rack (100) comprising a bottom assembly (120) and a top assembly (140). The bottom assembly (120) is secured to the top assembly (140) by a latching mechanism (160). Interposed between the top assembly (140) and the test tubes held by the bottom assembly (120) is a common seal. When the latching mechanism (160) is secured, a liquid-tight seal between the top assembly (140) and the test tubes (50) is created by the common seal. Figure 1 shows a side view cross section of the instant invention.

Description

BACKGROUND OF THE INVENTION

1. FIELD OF THE INVENTION

The present invention relates generally to a test tube rack, and, more particularly, to a test tube rack assembly with a common liquid-tight test tube seal over all the test tubes in the rack.

2. DESCRIPTION OF RELATED ART

Biological or chemical analysis and culture testing requires extensive handling, manipulation and transportation of individual test tubes. Each of these test tubes are individually capped and, typically, held in a rack. Such racks consist of a pair of plate members held in spaced parallel relationship and provided with an array of aligned apertures for receiving the individual test tubes. During analysis and testing, the individual test tubes are continuously removed from the rack and capped and uncapped by a lab technician for the addition of reagents, denaturation, vortexing, and withdrawal of samples from the test tubes. This procedure increases the processing time and can result in spillage of the contents, the evaporation of the specimen due to extended periods of not being recapped, and damage to the test tubes .

It is therefore highly desirable that the test tubes be held securely in position in a rack during manipulation and transportation and have a common seal to eliminate the capping and recapping of each test tube in order to save processing time and minimize the handling of the individual test tubes.

SUMMARY OF THE INVENTION The invention provides a test tube rack assembly that overcomes these problems . According to one embodiment , the test tube rack assembly comprises a bottom assembly and a top assembly. The bottom assembly includes a pair of parallel sidewalls and a plurality of spaced apart superimposed parallel plates secured to the sidewalls. The plates include a top guide plate, a bottom guide plate and a base plate. Each of the guide plates have an array of apertures each for receiving a test tube. Each of the apertures are vertically aligned with a corresponding aperture in each other guide plate. The top assembly includes a top plate and a pair of parallel sidewalls. A common seal is interposed between the top plate and the test tube. A latching mechanism secures the top assembly to the bottom assembly to form a liquid-tight seal over all the test tubes by the common seal . The common seal comprises a foam sheet adhered to the top plate. The common seal may also include a sealing sheet and/or a disposable sealing film. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a side view of one embodiment of the rack assembly. ^' DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Certain preferred embodiments of the present invention will now be described with reference to the drawings. Turning first to Fig. 1, a test tube rack assembly 100 according to the present invention is shown. The rack assembly generally includes a bottom assembly 120 and a top assembly 140 secured to the bottom assembly 120 by a latching mechanism 160.

The bottom assembly 120 includes a base plate 122, a pair of spaced apart guide plates 124, 126, a front plate 128, a back plate (not shown), and a pair of side plates 130. The front plate 128 and the back plate are bent up from base plate 122 to add stiffness to the rack 100.

Guide plate 124 is spaced apart from base plate 122 and disposed between base plate 122 and guide plate 126. The plates 122, 124, and 126 are disposed substantially parallel to each other and are held in spatial and parallel relationship by way of the parallel disposed sidewalls 130.

Sidewalls 130 are provided in one side with shallow parallel grooves or supports 132 in which are inserted, or support the ends of the guide plates 124 and 126. In alternate embodiments, as illustrated in Fig. 1, guide plates 124 and 126 are supported by standoff members 134 which are secured to the base plate 122 by a stud insert 136. As illustrated in Fig. 1, side plates 130 are integral and- bent up^" from base plate 122. Although, in alternate embodiments, side plates can be separate members having a groove and adapted to receive the end edges of base plate 122. The sidewalls 130 preferably project above the upper guide plate 126 to form a protecting wall for the test tubes disposed in the rack 100.

Plates 122, 124, and 126 and sidewalls 130 of the bottom assembly 120 may be constructed of, for example, an anodized aluminum, stainless steel, or the like. It will also be readily apparent that these plates and sidewalls may be constructed of any appropriate material other than metal, such as, for example, plastic, or of partly plastic and partly metallic materials. Plastic material such as, for example, acryllic plastic or the like, can be opaque, transparent or colored in any appropriate arrangement or color combination for the purpose, for example, of distinguishing a rack holding a particular type of test tubes or culture tubes from other racks. These components can also be molded partially or as a whole rather than assembled of united single elements.

The diverse elements of plates 122, 124, and 126 and of sidewalls 130 forming the rack 100 can be cemented together at their engaged surfaces by way of any appropriate cement or solvent for the particular type of plastic or other material used, or alternatively, fastened together by threaded members or the like.

Each of the guide plates 124 and 126 has a plurality of apertures (not shown) disposed, for example, in regular rows, each row having the same number of apertures . Each aperture of the lower, or intermediary, guide plate 124 is aligned with a corresponding aperture in the higher guide plate 126.

The bottom assembly 120 holds a plurality of test tubes, or like receptacles, passed through the pair of aligned apertures of the guide plates 124 and 126. The bottom of the test tubes 50 engage into recess (not shown) in the base plate 122. Each recess in base plate 122 aligns with a corresponding pair or apertures in guide plates 124 and 126.

The top assembly 140 includes a top plate 142, a pair of spaced apart side plates 144, a foam sheet 148 and a sealing sheet 150.

As illustrated in Fig. 1, sides plates 144 are integral with and bent down from top plate 142. Although, in other embodiments, side plates 144 can be separate members cemented or fastened to the edged surfaces of top plate 142.

Top plate 142 and side plates 144 may be constructed of, for example, an anodized aluminum, stainless steel, or other appropriate metal, plastic, or partly plastic and partly metal materials . The foam sheet 148 adheres to the inside surface of the top plate 1:2 by, for example, an adhesive, such as, for example, hot melt, acrylic, or synthetic rubber based adhesives, or, alternatively, by heat spot welding. The foam sheet is impermeable in nature. In particular, the foam sheet does not soak up fluids or permit fluids to pass through it. The foam sheet should also maintain its shape and be resilient at elevated temperatures. In one embodiment, the foam sheet 148 is a soft, low compression foam, such as, for example, a closed cell silicone foam. One suitable closed cell silicone foam is available as Poron^®, Model BF-1000 from Rogers Corporation (Woodstock, CT) .

The sealing sheet 150 is adhered to the bottom surface of the foam sheet 148 by, for example, an adhesive, such as, for example, hot melt, acrylic, silicone, or synthetic rubber based adhesives, or, alternatively, by heat spot welding. The sealing sheet is impermeable in nature. In particular, the sealing sheet does not soak up fluids or permit fluids to pass through it. The sealing sheet should also maintain its shape and be resilient at elevated temperatures. The sealing sheet is preferably inert and stable so as not to react with the components in the test tubes 50. For example, one suitable sealing sheet is made of a solid silicone rubber and is available from McMaster-Carr Supply, Co. (Chicago, IL) . The latching mechanism 160 secures the top assembly 140 to the base assembly 120. As illustrated in Fig. 1, the latching mechanism is a draw latch which securely clamps the bottom and top assemblies 120 and 140 together. Although any latching mechanism known in the art that secures the top assembly 140 to the base assembly 120 so that the contents are maintained within the test tubes can be used.

A sealing film 152 is placed between the top of the test tubes 50 and the bottom surface of the sealing sheet 150. The sealing film 152 should have the similar properties as the sealing sheet 150 but is meant to be disposable since the sealing film 152 is placed over the top of the test tubes and the contents of the test tube may come into contact with^* the sealing film 152. One suitable sealing film is available as DuraSeal^® from Diversified Biotech (Boston, MA).

It should be understood that a common seal can be created over all of the test tubes by use of only the foam sheet 148. However, it may be preferred that the common seal include both sealing sheet 150 and sealing film 152 to avoid contaminating the foam sheet 148 with the contents of the test tubes 50 and the need to clean or wipe off the foam sheet 148 after every use. In one embodiment, as shown in Fig. 1, the top assembly 140 includes a handle 180 secured to the top plate 142 by, for example, threaded members 182.

In use, uncapped test tubes or like receptacles or containers 50 are loaded onto the bottom assembly 120 through the corresponding apertures of guide plates 126 and 124. While loaded on the bottom assembly 120, reagents or other additives may be deposited into the test tubes or containers and samples may be removed from any one of the tubes, since each of the test tubes are not capped. The sealing film 152 is laid over the top of each tube or container followed by the top assembly 140. When the top assembly 140 is brought down over the base assembly 120, sidewalls 144 of the top assembly 140 are designed to fit between sidewalls 130 of the bottom assembly 120 to prevent the top assembly 120 from moving or shifting horizontally from the base assembly 120. The top assembly 140 is then secured to the bottom assembly 120 by latching mechanism 160 to create a common liquid-tight seal over the individual test tubes by use of the foam sheet 148, and optionally a sealing sheet 150 and a sealing film 152. This common seal eliminates the need to recap the individual test tubes and allows the entire rack to be immersed in a high temperature bath for denaturation or placed on a robotic sampling platform or vortexer deck. The rack assembly of the present invention can further be modified, to facilitate positioning and clamping the entire assembly onto an orbiting vortexer platform (i.e. beveling the corners, use of locating pins, etc.) in order to vortex all of the test tubes in the rack assembly at the same time.

It will be apparent to those skilled in the art that various modifications and variations can be made in the device of the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention embraces all such modifications and variations within the spirit and scope of the appended claims.

Claims

1.^" A test tube rack comprising: a bottom assembly comprising a pair of parallel sidewalls and a plurality of spaced-apart superimposed parallel plates secured to the sidewalls, the plates comprising a top guide plate, a bottom guide plate and a base plate, each of said guide plates having an array of apertures each for receiving a test tube, each of said apertures being vertically aligned with a corresponding aperture in each other guide plate; and a top assembly including a top plate and a pair of parallel sidewalls; a common seal interposed between the top plate and the test tubes; and a latching mechanism for securing the top assembly to the bottom assembly to form a liquid-tight seal over all the test tubes by the common seal.

2. The rack of claim 1, wherein the common seal comprises a foam sheet adhered to the top plate of the top assembly.

3. The rack of claim 2, wherein the foam sheet is a closed cell silicone foam.

4. The rack of claim 2, wherein the common seal further comprises a sealing sheet adhered to the foam member.

5. The rack of claim 4, wherein the sealing sheet is a solid silicone rubber.

6. The rack of claim 4, wherein the common seal further includes a sealing film interposed between the sealing sheet and the test tubes.

7. The rack of claim 1, wherein the latching mechanism is a draw latch.

8. The rack of claim 1, wherein the top plate is provided with a handle.