A New Sensitive Spectrophotometric Determination of Butachlor

A new sensitive spectrophotometric method was developed for the determination of widely used herbicide butachlor. The method is based on acidic hydrolysis of butachlor to 2, 6-diethyl amine, followed by coupling with diazotized aniline in acidic medium. The absorption maxima of the orange dye compound formed was measured at 490 nm. Beer's law was obeyed over the concentration range of 10-40 mu g (0.1 ppm to 0.4 ppm) in a final solution volume of 10 mL. The molar absorptivity, Sandell's sensitivity and correlation coefficient were found to be 7.07x10(2) L mol(-1) cm(-1), 0.20 mu g cm(-2) and 0.963 respectively. The standard deviation and relative standard deviation were found to be +/- 0.009 and 1.98% respectively. The method was simple sensitive and free from interferences of other pesticide and diverse ions. The method was successfully applied to the determination of butachlor in environmental and biological samples.