[Rapid determination of internal resistance in an electricigenic microorganism reaction system]

Internal resistance (R(int)) is an important parameter for kinetic studies on an electricigenic microorganism reaction system (EMRS). The traditional polarization curve measurement method is too laborious and tedious, usually leads to remarkable disturbance on system running. An improved method was put forward in this study, by decreasing the adjustment range of the external resistance value (R(ext)). In the situation of 10 omega of R(ext) step length and 1 min of voltage stabilization time, the whole test can be finished in 10 min, and the differences of the system current before and after R(int) determination were less than 20 microA. Different stabilization time has little influence on the results. Though to shorten the R(ext) step length can lessen the disturbance on the system running,it simultaneously leads to a larger measurement errors because of the multimeter precision limitation. The method advanced may be used to monitor the real-time R(int) change of EMRS.