Apparatus and method for supply of sample and sheath liquids to analytical flow cell

Claim 2

Apparatus for the concomitant supply of a first fluid, from selected one of a plurality of separate sources (40,42,44) of different first fluids, and a second fluid, from a selected one of a plurality of separate sources (96,98,100) of different second fluids, respectively, to a sheath stream flow cell analysis means which include a sheath stream flow cell (12), which apparatus comprises flow directing and control means (22) operatively associated with each of said separate first and second fluid sources, and said sheath stream flow cell, respectively, said flow directing and control means being operable to connect the selected ones, only, of said separate first and second fluid sources, and said sheath stream flow cell, for concomitant flow of said selected first and second fluids through said sheath stream flow cell.

Claim 3

Apparatus according to claim 1 wherein, said flow directing and control means comprise conduit means (68,72, 80 to 86, 94,118,120,112) connecting said pluralities of said first and second fluid sources and said sheath stream flow cell, and valve means (88,90,92,110,112,114,138,148,150) operatively associated with said conduit means and operable to control fluid flow therethrough for selection of said first and second fluids; and wherein said sheath stream flow cell analysis means comprises detecting means (49,51, 53,55) operatively associated with said sheath stream flow cell, said detecting means being operable to detect respectively different characteristics of said first fluids.

Claim 4

Apparatus according to claim 1 or 2, further comprising, pump means (34,36,38) operatively connected to said flow directing and control means and to said sheath stream flow cell and operable to concomitantly pump the selected ones of said first and second fluids from the respective fluid sources to said sheath stream flow cell for concomitant fluid flow therethrough.

Claim 5

Apparatus according to claim 3 which comprises variable speed pump drive means (16) operatively associated with said pump means and operable to drive the latter at selected pumping rates in accordance with first and second fluid selection whereby, the selected ones of said first and second fluids may be concomitantly pumped through said sheath stream flow cell at respectively optimal flow rates.

Claim 6

Apparatus according to claim 3 or 4, wherein said pump means (34,36,38) comprises differential pump means operatively connected to the inlet means (26,28) and outlet means (30), respectively, of said sheath stream flow cell, said differential pump means being operable to pump the selected one of the first of said fluids to said sheath stream flow cell inlet means at a first flow rate, and to concomitantly aspirate the selected ones of the first and second of said fluids through said sheath stream flow cell outlet means at a second, and greater flow rate whereby, the flow rate of the second of said fluids through said sheath stream flow cell will be equal to the difference between said second and first flow rates, respectively.

Claim 7

Apparatus according to claim 5, which is arranged so that, in use, said first fluids comprise a plurality of sample liquids, and said second fluids comprise a plurality of respectively optically compatible sheath liquids, and wherein said differential pump means comprise a sample liquid pump (34) which is connectable by said flow directing and control means to the selected one of the plurality of sample liquid sources and to the sheath stream flow cell inlet means to pump the selected sample liquid from said sample liquid source to the sheath stream flow cell inlet means, and a sheath liquid pump (36) which is connectable by said flow directing and control means through the sheath stream flow cell outlet and inlet means, respectively, to the selected one of the plurality of sheath liquid sources to concomitantly aspirate the selected sheath liquid, and the selected sample liquid as pumped by the sample liquid pump, through said sheath stream flow cell.

Claim 8

Apparatus according to claim 6, wherein means are provided to pressurise the respective sources of said sheath liquids.

Claim 11

A method according to claim 8, further comprising varying the rates at which the selected ones of said first and second fluids are pumped for flow through said sheath stream flow cell in accordance with the selections of said fluids whereby, the selected ones of said first and second fluids may be concomitantly flowed through said sheath stream flow cell at respectively optimal flow rates, and wherein a characteristic of the selected one of said first fluids is detected, as the same is flowed through said sheath stream flow cell, in accordance with the selection of said fluid.

Claim 12

A method according to claim 9, wherein the selected one of the first of said fluids is pumped to said sheath stream flow cell at a first flow rate, and the selected ones of the first and second of said fluids are concomitantly aspirated through said sheath stream flow cell at a second, and greater flow rate whereby, the flow rate of the second of said fluids through said sheath stream flow cell is equal to the difference between said second and first flow rates, respectively.