Patent ID: 7635452

Claim:
A system for measuring diffusion of a compound across a membrane comprising: a first base having first and second opposed surfaces and having a plurality of hollow projections extending outwardly from the first surface, each hollow projection having a tapered tip with an opening therein and a respective cavity contiguous with the opening disposed within the projection; a second base having first and second opposed surfaces, the first surface of the second base having a plurality of recessed tapered openings therein adapted to engage the plurality of hollow projections, each recessed tapered opening being contiguous with a respective cavity that extends into the second base; a membrane contacting the recessed tapered openings and the tips of the hollow projections, wherein the first base is fastened to the second base by a first fastening means, and wherein: a) each cavity within a hollow projection extends through the first base and forms an opening at the second surface of the first base; or b) each cavity within the second base extends through the second base and forms an opening at the second surface of the second base; or c) each cavity within a hollow projection extends through the first base and forms an opening at the second surface of the first base, and each cavity within the second base extends through the second base and forms an opening at the second surface of the second base; and a retaining plate having perforations therein adapted to allow the hollow projections to pass therethrough, wherein the retaining plate is fastened to the second base by a second fastening means, wherein the membrane is disposed between the second base and the retaining plate.