OBJECTIVETo establish the mothod to dectect the microdialysis recovery of HCPT and to investigate the influencing factors, thus to supply experimental basis for in-vivo microdialysis of HCPT.

METHODThe in vitro recovery of HCPT was detected by concentration difference method (increment method and decrement method). The influence of flow rates, medium concentration and temperature on the HCPT recovery and the stability were studied.

RESULTThe recovery detected by increment method was the same as by decrement method. The recovery was independent of HCPT concentrations in the medium. The hydroxycamptothecine recovery had good stability and increased as the temperature rose.

CONCLUSIONMicrodialysis sampling can be used for the pharmacokinetic study of HCPT. Retrodialysis can be used for the determination of the HCPT in vivo recovery.