Abstract:
A lid for a liquid sample container is provided which includes an opening for transferring the sample into a further container for conducting the necessary tests and a flexible portion, which allows the sample to be expelled through the opening. The opening is normally closed by a detachable closure which can also be used to re-seal the opening after the desired quantity of the sample has been withdrawn. An apparatus is also provided for obtaining dual liquid samples, which comprises two sample containers, wherein one container is retained within a recess in the other to result in a unitary structure. Further a method of obtaining liquid samples is provided which utilizes containers of the present invention.

Description:
This is a Continuation In Part Application of patent application Ser. No. 08/897,301, now U.S. Pat. No. 5,975,373. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to devices for collecting and transporting liquid samples. More particularly, the subject devices are used for collecting and transporting samples of liquids for analytical testing. 
     2. Description of the Prior Art 
     The sampling of fluids for diagnostic or evidentiary purposes is very common. Such fluids, which include urine, blood, water, milk etc., arc collected in a specimen container and transported to a laboratory where they are analyzed to determine the presence of infections or contaminants such as drugs, alcohol etc. Under such circumstances, the collected sample must be maintained uncontaminated until the various testing procedures have been concluded. Containers for this purpose are common and usually comprise a plastic container having a secure lid. 
     The first step in analyzing the sample is normally the extraction of an aliquot of the collected fluid. Since the collected samples may pose a biohazard risk, great care must be taken to ensure that the liquid sample is not spilled during the handling of the container or the extraction of the desired aliquot. Further, in order to protect the accuracy of the analytical results, it must be ensured that no contaminants mix with the sample. 
     It is now preferred for the analytical process to be automated which involves the use of robotics to handle the specimen container and to conduct the various chemical and biochemical tests on the liquid sample. To conduct the desired tests, an aliquot of the sample is extracted from the vial and passed into a testing chamber (a test tube for example). As mentioned above, it must be ensured that the fluid sample is not spilled onto any part of the apparatus and that, during the extraction of such aliquot, another sample or other material does not contaminate the sample. Thus, specimen containers must be designed to be suitable for use in both manual and automated analytical processes. 
     Another issue arises in cases where biological samples are collected for evidentiary purposes. In such situations, the established protocols call for two samples of fluid to be collected and maintained in separate containers. One of such samples proceeds through the analytical process while the second is maintained uncontaminated for later reference if needed. In these cases it is important to maintain a proper chain of custody of the two samples so as to prevent tampering. Normally, the sample is collected in a collection cup and separated into transport containers, which are attached together, usually by rubber bands, until they reach the laboratory. Although the containers are labeled, they can easily be misplaced rendering further verification of the tests impossible and corrupting the chain of custody. 
     To address the safe transfer of the desired aliquot of the sample, various modifications to the container lid have been proposed. An example of such modification is described in U.S. Pat. No. 5,395,590 wherein Swaniger et al. teach a valved plastic lid for a specimen container. The &#39;590 lid includes a valved opening in the center which comprises a number of slits, which, due to the elasticity of the plastic material, are normally closed. However, upon applying an inward force to the lid, the slits open and allow the contained fluid to pass through. In extracting fluid from a container having such lid, the opening of a second container, such as a test tube, is placed over the opening in the lid and the two containers are inverted. The first container is then forced downward thereby causing the slits in the lid to open and allowing fluid to enter the second container. However, the lid taught in the &#39;590 patent has certain disadvantages. For example, the slits in the lid can be forced open prior to the testing process by applying pressure thereto and thereby allowing contaminants to enter the container. Similarly, the collected sample may also be inadvertently spilled thereby requiring a separate closure until the sample is extracted. Further, the manufacture of such a complicated structure adds to the cost of such a lid. 
     In U.S. Pat. No. 4,917,867, Jensen et al. teach an apparatus for the collection of dual biological samples. This reference describes a kit comprising a container containing two sample vials and other items to obtain the desired samples. After collecting the samples, the vials are placed back into the main container. Although accounting for the chain of custody during transfer, the apparatus of this reference requires the separation of the sample vials prior to the analysis process thereby resulting in the possibility of one of them being misplaced. 
     Thus a need exists for a specimen container which overcomes the above-identified deficiencies in the known devices. 
     SUMMARY OF THE INVENTION 
     Therefore, the present invention provides, in one aspect, an apparatus for collecting and transporting a liquid sample comprising: 
     a first container having a receptacle and a lid, the lid including a means for metering and dispensing a portion of the sample; 
     the first container receptacle having an internal cavity opening to the bottom of the first container; 
     a second container having a receptacle and a lid; 
     the second container being received within the cavity in the first container receptacle and being releasably secured within the cavity. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features of the preferred embodiments of the invention will become more apparent in the following detailed description in which reference is made to the appended drawings wherein: 
     FIG. 1 is a cross sectional view through the central longitudinal axis of a specimen container in accordance with one embodiment of the present invention. 
     FIG. 2 is a cross sectional view of a specimen container in accordance with another embodiment of the present invention. 
     FIG. 3 is a side view of the container of FIG. 2 with the lid removed. 
     FIG. 4 is a bottom view of the container of FIG.  3 . 
     FIG. 5 is a cross sectional view of a sample container lid in accordance with another embodiment. 
     FIG.6 is a top view of the lid for the container of FIGS. 1 or  2 . 
     FIG. 7 is a cross sectional view of a sample container lid in accordance with another embodiment. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to FIG. 1, a specimen container in accordance with a first embodiment is shown generally at  10 . The container includes a lid  12 , according to an embodiment of the invention, and a receptacle  14  for containing the liquid sample. The receptacle  14  is of a standard design and includes a threaded upper portion  16  which engages a corresponding threaded portion  18  of the lid  12 , thereby allowing the lid to be secured to the receptacle. In the preferred situation, the lid is formed of a flexible thermoplastic material and the receptacle is of a generally cylindrical structure also formed of a thermoplastic material. Preferably, both the lid and receptacle are formed of polypropylene to allow for recycling of the materials. 
     In the embodiment shown in FIG. 1, the lid  12  includes a well  20  and a spout portion  22  located in the center of the lid. The well  20  of the lid  12  is bounded by a bottom surface  24  and a sidewall  25 . Bottom surface  24  generally slopes upward from its junction with the sidewall  25 , at the outer circumference, to the center spout portion  22 . The spout portion  22  comprises a funnel  28  having an opening  26 . The spout portion further comprises an uneven bearing surface  30  the purpose of which is described below. Bearing surface  30 , in a preferred embodiment, has a plurality of ribs  31  that radiate in a direction towards the outer circumference of the lid. In an alternative embodiment, the ribs may be replaced by grooves. 
     The opening  26  is dimensioned so that, when the container  10  is inverted with the closure  32  removed, air cannot enter the container due to the surface tension of the liquid contained within. Accordingly, the liquid is prevented from exiting the container. For example, for samples comprising water or aqueous solutions, the opening  26  has a diameter of ≦0.04 in. For other liquids, the diameter of the opening  26  will depend upon its surface tension. 
     The opening  26  is sealed by a closure  32 , which is integrally formed with the lid  12  and is connected to the funnel  28  by means of a junction  34 . The junction  34  is made of the same thermoplastic material as the funnel  28  and the closure  32  but is of a thinner construction. The weakness of the junction  34  allows the closure  32  to be separated from the funnel  28  upon application of sufficient force. The closure  32  includes a pin  36  and a plurality of projections  38 , which facilitate the manual, or automated gripping of the closure  32 . In a preferred embodiment, the projections  38  comprise a plurality of arms that extend upwardly and radially thereby forming a concave region  40  around the pin  36 . Alternatively, the projections  38  can consist of ribs. 
     The outer surface  42  of the side wall  25  includes a rim  43  which extends radially outward of the lid  12  and which bears against the inner surface  44  of the receptacle  14  to form, preferably, an air tight seal therewith when the lid is engaged on the receptacle. The bottom surface  24  of the well  20  includes a weakened portion  46  between the sidewall  25  and the spout portion  22 . The weakened portion is formed by reducing the thickness of the thermoplastic material in the desired region. Thus, the bottom surface of the lid is made flexible in the region of the weakened portion  46  for the purpose described below. 
     Preferably, the outer surface  19  of the lid  12  includes conventional vertical ribs to aid in detaching the lid from the receptacle  14 . 
     Further, in the preferred embodiment, the closure  22  does not extend above the rim  27  of the lid  12  so as to permit stacking of the containers  10  and the application of a security sealing tape, when necessary. 
     In operation, the lid  12  is removed from the receptacle  14 , a fluid sample is introduced and the lid is secured to the receptacle. For withdrawing the desired aliquot of the sample, the closure  32  is twisted causing the junction  34  to break and thereby exposing the opening  26 . The projections  38  assist in removal of the closure  32  by providing leverage for such twisting motion. A test tube (not shown) or other similar container for receiving the aliquot is inverted and placed over the spout portion  22  so that the rim of the opening of such test tube rests on the uneven bearing surface  30 . Both the specimen container  10  and the test tube are then inverted thereby causing the fluid sample to fill the spout portion  22  and particularly the funnel  28 . Since air is prevented from entering the container  10 , the fluid sample does not leak from the opening  26 . To extract the aliquot, the specimen container  10  and/or the test tube are moved towards each other causing the weakened portion  46  to flex inwardly and, in turn, forcing the spout portion  22  towards the interior of the receptacle  14 . The inward movement of the spout portion  22  leads to an increase in pressure within the receptacle which, in turn, forces a portion of the fluid in the container to exit the opening and to collect in the test tube. The weakened portion  46  can be designed to deliver a specific, or controlled, volume of liquid. This is achieved by designing the weakened portion to flex by a specified amount. 
     The ribs  31 , on the uneven bearing surface  30  of the lid, provide channels for the air in the test tube to escape when displaced by the entering fluid. 
     The specimen container is then separated from the test tube and turned upright. This removes the inward force on weakened portion  46  causing it to resume its normal raised position thereby reducing the internal pressure of specimen container  10 . The vacuum created within the container due to such pressure drop causes any liquid remaining in the opening  26  and any drop clinging to the opening to be sucked back into the receptacle and prevents any further fluid from dripping out of the opening  26 . 
     In order to prevent spillage of the sample fluid after the above process, the opening  26  is closed by heat sealing. In the preferred method, the heat sealing step involves the application of a foil over the opening and the application of heat onto the foil. In such manner, the heating source does not come into contact with the opening and prevents such source from being contaminated by the sample. In the alternative, the closure  32  may be inverted and the pin  36  inserted into the opening  26 . To accommodate the latter closing method, the region  40  is designed to cover the funnel  28 . 
     As mentioned previously, these testing steps can be carried out in an automated process wherein robotics are used to manipulate the containers, test tubes and other components. 
     In another embodiment, the test tube need not be in contact with the lid  12 . In this embodiment, the contained fluid can be expelled in the same manner as above but by using a retaining device to support the container  10  above the test tube. 
     FIG. 2 illustrates a further embodiment of the present invention for handling a fluid sample, which has been transferred into two separate containers. In this embodiment, like elements are indicated with like reference numerals and the letter “a” is added for clarity. The specimen container according to this embodiment is indicated generally at  10   a . The complete specimen container includes a first fluid sample container  49  having a lid  12  such as described above. Alternatively, the lid for the first container  49  can be any conventional lid known in the prior art. In the embodiment shown, the generally cylindrical first container  49  also includes a fluid sample receptacle  14   a  comprising a fluid containing chamber  50  and legs  52  and  54  which define a generally cylindrical recess  56 . A second fluid sample container  58  is disposed within the recess  56 . The second container  58  comprises a receptacle  60  and a lid  62 . As above, the lid  62  is screwed onto the receptacle  60 . To ensure that separation of the two containers does not occur, the exterior surface  64  of the second container  58  and the surface of the recess  56  are ribbed so as to provide a friction fit there between. 
     The lid  62  of the second container  58  includes an annular recess  66  around its outer edge and directed towards the interior of the receptacle  60 . A lid of this structure is described in U.S. Pat. No. 5,460,283. The recess  66  is positioned so that, when the lid  62  is engaged on the receptacle  60 , the outer wall  68  of the annular recess  66  is pressed against the inner wall  70  thereby forming a seal between the lid  62  and the receptacle  60  to prevent leakage of the contained liquid. In an alternative embodiment, a conventional lid may be used for the second container  58 . In another embodiment, a rim  72  may be provided on the inner wall  70  of the receptacle  60 . The rim  72  is then biased against the outer wall  68  of the recess  66  when the lid is secured. 
     In the preferred embodiment, the second container  58  does not extend beyond the legs  52  and  54  of the first container so as to enable the complete specimen container  10   a  to stand on legs  52  and  54 . 
     FIGS. 3 and 4 illustrate different views of the receptacle  14   a . As shown the legs  52  and  54 , when viewed on end, are generally crescent shaped and follow the outer generally cylindrical surface of the receptacle  14   a . The receptacle  14   a  includes two slots  74  and  76  located between legs  52  and  54 . Slots  74  and  76  allow the lid  62  of the second container  58  to be grasped so as to permit extraction of the second fluid container  58  from the recess  56  of the first fluid container  49 . 
     In a further embodiment, the second fluid container  58  may be screwed into the recess  56  instead of using the friction fit as mentioned above. 
     In using the dual container  10   a  as described above, the second container  58  is first separated from the first container  49  and both lids  12  and  62  are removed. The liquid sample is transferred into receptacles  50  and  60 . Both lids  12  and  62  are replaced onto to the respective receptacles  50  and  60  and the second container  58  is inserted into the recess  56  as shown in FIG.  2 . The first container  49  contains the sample to be tested while the second container  58  contains a duplicate sample for future reference. During the testing process, the steps discussed above are followed. 
     A further, preferred embodiment of the lid is shown in FIG. 5 wherein like elements are identified by like reference numerals and wherein the letter “b” is used for clarity. The lid of this embodiment is shown at  12   b . The lid  12   b  has most of the same components as the previous embodiment of the lid  12  described above. However, the bearing surface  30   b  of this embodiment generally follows the slope of the funnel  28 . The bearing surface  30   b  includes ribs  31   b  to provide an uneven surface as described above. 
     FIG. 6 is a top view of the lid  12  and illustrates the ribs  31  of the bearing surface  30 . As shown, four ribs are provided which radiate outwardly from the center of the lid. 
     In another embodiment, the lids  12  and  12   a  can also be secured to the receptacle  14  by a snap fit. 
     FIG. 7 illustrates another embodiment of the invention wherein like elements are referred to with like numerals with the letter “c” added for clarity. In FIG. 7, the bearing surface  30   c  comprises a plurality of ribs  31   c  radiating from the center of the lid and lying on the bottom surface  24   c.    
     Although the invention has been described with reference to certain specific embodiments, various modifications thereof will be apparent to those skilled in the art without departing from the spirit and scope of the invention as outlined in the claims appended hereto.