Flow injection spectrophotometric determination of methamidophos using online hydrolysis.

ABSTRACT

A new protocol for the online spectrophotometric determination of methamidophos has been developed. The method is based on online hydrolysis of methamidophos, and the resulting hydrolyzed product is reacted with sodium nitroproside to form a colored complex. The calibration curve is linear over the concentration range of 0.5-20 microgml(-1), with a molar absorptivity of 2.5x10(4) L mol(-1) cm(-1). The method is fast and reproducible with a sample throughput of 90 samples/h. The method is successfully applied to formulations and real samples.