Patent ID: 7156996

Claim:
A multichamber microdialysis device comprising a plurality of sample chambers in close side by side arrangement, said sample chambers being defined by circumferential side walls having a first open end for taking up liquid samples into the sample chamber and a second open end providing an exchange opening, and a dialysate chamber for taking up a dialysate liquid, wherein the exchange opening of each sample chamber is covered with a separate semipermeable membrane fixed liquid-tight to the circumferential side walls of the sample chamber in such a manner to provide a diffusion exchange between the sample chamber and the dialysate chamber when the second end of the sample chamber is placed in contact with the dialysate liquid, and wherein a peripheral marginal section of each semipermeable membrane is clamped between a front face of the circumferential side wall of the sample chamber and a fixing part, wherein each fixing part comprises a ring-shaped portion presenting a circumferential mounting region and an annular wall extending from the perimeter of the ring-shaped portion, the diameter of said annular wall selected to allow frictional engagement of the annular wall with the circumferential side walls of the sample chambers, wherein the outer diameter of a region where the annular wall frictionally engages the circumferential side walls exceeds the sample chamber diameter by not more than 3 mm, the front face of the side wall consisting of an opposing ring-shaped circumferential mounting region wherein one of the mounting regions consists of a surface and a circumferential groove and the other mounting region consists of a surface and a protruding rib fitting into the groove, by which the membrane is pressed into the groove at its peripheral marginal section and clamped between the ring-shaped circumferential mounting region and the opposing ring-shaped circumferential mounting region.