Patent GB-1256378-A (GB)
Title: Apparatus for extracting a sample of a liquid from a source of the liquid
IPC: B01L3/00
Filed: 1969-10-27
Abstract: 1,256,378. Withdrawing body fluid samples. F. HOFFMANN-LA ROCHE & CO. A.G. 27 Oct., 1969 [21 Nov., 1968; 27 Dec., 1968], No. 52606/69. Heading R. [Also in Divisions B1; B8 and Fl] A sample storage unit comprises a block 1 defining tubular chambers 10 each pair of adjacent chambers being in communication via a passage 11, and end closure members 2, 3. The passages are arranged near the upper ends of the chambers so that the upper closure member 2 upon movement from the position h illustrated in Fig. 2 to the position b will close the passages 11. The block 1 is preferably transparent and is preferably formed by moulding a thermosetting material. The closure members are made of moulded  synthetic plastic or rubber. Each portion 21 may include a projection adapted to engage a groove in the internal wall of the respective chamber so as to locate the upper closure member in the position h. A projection, alternatively may be provided in each chamber and each portion may have a groove therein. The block or the closure members are provided with parts which can be easily pierced by a hollow needle.  A similar unit is illustrated in Fig. 4. In this unit passages 12, 16 are provided for insertion of hollow needles. The passage 12 is covered by a self sealing ribbon or tape 14 e.g. of rubber, and the passage 16 is covered by a self sealing rubber liner 35 which forms a first part of the closure member 3. The second part of the closure member 3 is of plastics and includes projections 39 for engaging in lower ends-of chambers 10, apertures 38 for permitting liquid to be extracted from the chamber, and an aperture 37 which permit passage of a needle into the passage 16. In a modification of the embodiment of Fig. 4 the lower end of the body 1 and the closure member 3 are identical with the upper end and closure member 2 respectively. In use the unit of Fig. 4 is inserted in a support 44 (Fig. 7) which has grooves 46 for receiving lugs 47 of a needle carrier 42. The needle 40, for extracting a sample of liquid from a source is releasably mounted in the carrier 42 by a catch 43 which engages a frusto-conical member 41 fast with the needle, and when the carrier is assembled on the support the needle extends through passage 16. A battery driven motor housed in a casing 50 drives a fan 51 to exhaust air from the unit via pipe 53 and an air exhaust needle extending through passage 12. Upon operation of the motor by actuation of a switch 52 liquid is sucked into the chambers 10, and after withdrawal of the air exhaust needle, the closure member 2 is pushed downwardly to close the passages 11. The means for creating a suction may include a piston and cylinder arrangement or an arrangement in which a flexible chamber (60) (Fig. 9 not shown) can be manually depressed to exhaust air therefrom via a one-  way valve (65) and subsequently released to permit displacement of air within the unit by liquid via a second one-way valve (66). A manually adjustable means (71) is provided for varying the rate of flow of liquid into the unit. The upper closure member has recesses 25 each of which may include a reagent therein e.g. separated from the liquid in the associated chamber by a diaphragm which is pierced e.g. by a needle, or ruptured by friction against the walls of: the associated chamber only when the upper closure member is moved to close the passages 11.