Swab assembly

A swab assembly ( 10 ) comprises an external housing ( 11 ) formed from two interengageable housing parts ( 12, 13 ). A hollow tubular member ( 14 ) having swab material ( 16 ) at one end is attached to one housing part ( 12 ) at the other end. The Interior of the tubular member ( 14 ) is closed off with a seal member and contains a suitable reagent ( 18 ) which is held in spaced disposition from the swab material by capillary action. When the assembly is to be used, the two housing parts ( 12, 13 ) are separated revealing the inner tubular member ( 14 ) and the swab material ( 16 ) can be utilised to collect a sample. If it is desired to dispense reagent ( 18 ) onto the swab material ( 16 ) prior to or after collection of the sample, the tubular member ( 14 ) can be deformed in the region of a seal ( 17 ) to separate the tubular member from the housing part ( 12 ) thereby allowing the reagent ( 18 ) to flow onto the material ( 16 ).

Referring now to the drawings there is shown in FIG. 1, a swab assembly 10 comprising an external housing 11 formed from two interengageable housing parts 12 , 13 . Each housing part 12 , 13 is formed from a plastics material and at least one housing part 12 is formed from a resiliently deformable plastics material. As shown in the drawing, one part of the housing 12 is shaped so as to be a push fit on an external surface of the other housing part 13 to provide the interengagement. Alternatively the one housing part 12 may engage an internal surface of the other housing part 13 or indeed the housing parts 12 , 13 may cooperate in any other suitable manner to achieve interengagement. Internally of the external housing 11 is a hollow tubular member 14 having swab material 16 at one end. An opposite end of the member is attached to an internal surface of the housing part 12 and a hollow interior is closed off with a seal member 17 . A reagent 18 of suitable form in a predetermined quantity, is contained within the interior of the hollow tubular member 14 between the seal member 17 and the swab material and is held in spaced disposition from said swab material 16 by capillary action. The hollow tubular member 14 is adapted to be frangible adjacent the seal member 17 and thus the tubular member may, in a preferred embodiment, comprise an area of weakness adjacent the seal member 17 which when distorted causes fracture of the tubular member 14 in the area of weakness. The seal 17 may comprise any suitable material such as, for example a wax, silicon based material or may just be an area in which the tubular member has been heat sealed or crimped. The seal provides an airtight liquid barrier in order that the capillary action can take effect. The swab material 16 may comprise any suitably absorbent material such as, for example cotton, sponge, synthetic or textile cloths. In use, the assembly is provided as shown in the drawing. Therefore, when, for example, the assembly is being used in the forensic field at a crime scene, the person wishing to utilise the assembly to collect a sample or specimen would firstly remove the hollow tubular member 14 from the outer housing 11 by disengaging the housing part 12 from the other housing part 13 by a sliding action. As the end of the hollow tubular member 14 is fixed into the housing part 12 , removal of the housing part 12 will mean that the tubular member 14 can be removed from the external housing 13 . Furthermore, by arranging for the tubular member 14 to be retained by the housing part 13 means that at no point does a person using the assembly have to touch the swab material 16 therefore reducing to a minimum the risk of contamination. Once removed from the housing part 13 , the swab material 16 can be used to collect a desired sample or specimen. The tubular member 14 is then replaced in the housing part 13 and the two housing parts 12 , 13 are interengaged to form the complete assembly. In this position it will be realised that the sample or specimen collected on the swab material 16 is held in a suitable protective environment where the risk of contamination is minimal. Depending upon the field in which the assembly is being used, it might be necessary to apply a suitable reagent to the swab material 16 prior to collection of a sample or specimen. This is usually the case in the field of forensic use but may also apply in other fields of use. If this is necessary, prior to use, the housing part 12 is deformed by a user in the region of the seal 17 on the tubular member 14 to such an extent that the area of weakness in the end of the hollow tubular member 14 is fractured. As the predetermined quantity of chemical reagent contained within the hollow tubular member 14 is held spaced from the swab material 16 by capillary action, as soon as the end of the hollow tubular member 14 is fractured and air can enter, the liquid flows down the hollow tubular member 14 and onto the swab material 16 . It will be realised that by use of capillary action to hold the reagent 18 spaced from the swab material 16 and then to deliver the reagent onto the swab material results in a particularly effective and controlled application of reagent to the swab material and hence the collected specimen. Once the reagent 18 has been delivered to the swab material 16 , the assembly can be used as described above. Alternatively it may be desirable or necessary that the reagent 18 is delivered to the swab material 16 after collection of the specimen and, in these circumstances, the outer housing part 12 is deformed by a user to cause fracture of the inner hollow tubular member 14 in the region of the area of weakness subsequent to collection of the sample or specimen and once the hollow tubular part 14 has been replaced in housing part 13 and the housing parts 12 , 13 have been interengaged to form the complete assembly. Alternatively, the reagent 18 may be delivered onto the sample or specimen collected on the swab material 16 before the complete assembly is formed. The choice of reagent 18 will vary according to the field of application of the assembly, for example in the field of forensic use a fixative or moistening agent may be a suitable reagent. It will be appreciated that with this arrangement, it is possible to provide a swab assembly which is particularly easy and simple to use effectively and in which it is possible to minimise the risk of contamination of collected specimens whilst also allowing accurate delivery of a suitable reagent to a swab material either prior to, or subsequent to, sample or specimen collection. Referring now to FIG. 2 , there is shown a second embodiment in which an end 101 of the housing part 102 is adapted for separation from the remainder of the housing part 102 to allow access to the hollow internal tubular member 103 . This allows a plunger member 104 of appropriate dimension to be inserted into a bore 106 of the tubular member 103 and used to push the swab material 107 from the end of the member 103 so as to be retained in the other housing part 108 . For this purpose the swab material 107 is adapted to be removable from the tubular member 103 . The plunger 104 has a boss part 109 which is of greater dimension than the bore 106 of the hollow tubular member 103 to prevent the plunger 104 being inserted completely into the bore 106 . In use, as disclosed in relation to the embodiment of FIG. 1 described above, liquid is released onto the swab material 107 by deforming the housing part 102 until the hollow tubular member 103 fractures adjacent the seal 111 . The swab is then removed from the housing part 108 , used for its purpose, and replaced in the housing part 108 . The end 101 of the housing part 102 is removed, for example by cutting and the plunger member 104 is inserted In the bore 106 of the hollow tubular member 103 and is pushed in until it engages the swab material 107 and is used to disengage the material 107 from the end of the hollow member 103 . The remaining part of the housing part 102 and tubular member 103 can be discarded and a cap (not shown) or similar provided to close off the open end of the housing thereby retaining the swab material in sterile conditions. It is of course to be understood that the invention is not intended to be restricted to the details of the above embodiment which are described by way of example only.