. The conditions obtained were 0.6% (w/v) rhodanine, 70% (v/v) ethanol, 0.9molL-1 NaOH, 2.0mLmin-1 flow rate, 75 µL injection loop and 600 cm mixing tubing length, respectively. Comparative optimizations of the experimental conditions were also carried out by multivariate or simplex optimization method. The conditions obtained were 1.2% (w/v) rhodanine, 70% (v/v) ethanol, 0.9molL-1 NaOH, 2.0mLmin-1 flow rate, 75 µL injection loop and 600 cm mixing tubing length, respectively