APPARATUS FOR TAKING SAMPLES OF LIQUID

1276903 Sampling and dispensing apparatus RHONE-POULENC SA 9 Oct 1969 [10 Oct 1968] 49741/69 Heading B1X [Also in Division A5] Blood sampling apparatus comprises a receiving tube (1) Fig. 2 (not shown) having an open end and a closed end, a piston 2, Fig. 3, axially slidable within the tube (1) and having a puncturable resilient wall 14, a support tube 4 insertable into the open end of the tube (1) and carrying a hollow needle 10, and interengaging means on the support tube 4 and the piston 2 to attach one to the other. The tube 4 is formed at one end with a narrow bore duct 6 which is in communication with a connecting member 7, a suction tube 9 and preferably a hollow needle 8. The hollow needle 10 is fitted into the duct 6 and the other end of the tube 4 is formed with three slots 11 between axially extending arms 12 which are outwardly flared and have an internal rib 13 at their extremities. In use, the tube (1) is placed over the tube 4 and moved along until the needle 10 is driven through the wall 15 of the piston and simultaneously the ribs 13 engage the circular groove 3 of the piston 2. The part of the tube (1) behind the piston is thus placed in fluid contact with a source of liquid via the suction tube 9 and the needle 8 and on withdrawal of the tube (1), the liquid fills the tube. The piston 2 is retained within the tube (1) by lugs (14) while the arms 12 pass out of the tube and release the piston as they tend to move outwards on release of the compressive action of the tube (1), the piston thus forming a fluid tight stopper for the tube (1). In a modification, the needle 10 may be pointed at both ends, fixed to an end member fitted onto the piston and a puncturable, resilient seal may be placed over the end of the duct 6. A plurality of tubes 4 may be placed in parallel with a commonduct (6a) Fig. 4 (not shown) and ball valves (16) may be placed in the individual ducts 6. A protective box (17), Fig. 5, (not shown) may be used with the arrangement of Fig. 4, which box contains the appropriate number of tubes (1) and pistons therein and is formed with orifices (18) and lugs (19). The apparatus may be made from a transparent plastics material, e.g. polyethylene &c. A detachable member, not shown, may be used with the embodiment of Fig. 4 for the simultaneous withdrawal of the plurality of tubes (1) and a sodium citrate or heparin solution may be placed within the tubes (1) or in crystalline form in the duct 6 prior to the introduction of the liq