Objective:To establish a method for the relative recovery (RR) of chlorine-e6 in microdialysis probe and to investigate the effect of the concentration

time and temperature on RR in chlorin-e6 microdialysis probe. Method: Gain method and loss method were used for the study. The concentration of chlorine-e6 in micro-dialysate samples was detected by HPLC and calculated probe RR with the formula used for the probe. Result: At the same concentration

RR decreased with the increase of the flow rate in the two methods. RR detected by gain method was similar to that detected by loss method. At the same flow rate

the concentration had no obvious effect on RR. RR kept steady within 12 hours

and increased obviously with the temperature. Conclusion: The influencing factors on RR in chlorin-e6 microdialysis probe are confirmed. The probe recovery obtained by gain method is similar to that by loss method. Retrodialysis can be used for the determination of the chlorine-e6 in-vivo recovery.