Patent ID: 7404490

Claim:
A flow channel for use with dispensing apparatus dispensing a sample flow and a carrier flow, said flow channel capable of developing a circumferentially consistent, laminar, annular separation flow for a range of inlet and outlet flow ratios, said flow channel comprising: (a) a core having an inlet end and an outlet end and a cylindrical wall; (b) a cylindrical shell having an inlet end and an outlet end and a cylindrical wall, wherein said cylindrical wall has a diameter larger than that of said cylindrical wall of said core and being concentrically aligned with said core, creating an annular flow volume; (c) an inlet adaptor connecting said carrier flow to said channel; (d) a flow distributor that deflects said carrier flow to a laminar, circumferentially uniform, annular flow; (e) an inlet splitter providing a contact point for said sample flow and said carrier flow; (f) an outlet splitter converting said sample flow and said carrier flow into a positively selected outlet fraction and a negatively selected outlet fraction; and (g) an outlet adaptor for separately conveying one of said positively selected outlet fraction and said-negatively selected outlet fraction for further use.