A stopped-flow microdialysis sampling-flow injection system for automated multivessel high resolution drug dissolution testing

A simple and robust flow injection on-line microdialysis system for multive ssel drug dissolution testing is described. Microdialysis probes were used for sampling from the dissolution media. A stopped-flow dialysis mode with a 50-s stopped-flow period followed by 10-s injection at a perfusion rate o f 2.8 ml min(-1) for each probe was used to achieve high resolution of diss olution events using relatively simple equipment and operation. The precisi ons obtained for simultaneous monitoring of dissolution profiles for six ta blets were all better than 0.9% (RSD n = 80) and the overall sampling frequ ency of the system was 360 and 60 h(-1) for each test vessel. The dissoluti on profiles of isoniazid fast-release tablet from three sources were determ ined to demonstrate the performance of the system. (C) 1999 Elsevier Scienc e B.V. All rights reserved.