Determination of carbofuran in pesticide formulations by flow injection spectrophotometry

Abstract

A¯ow injection spectrophotometric method for the determination of carbofuran in commercial pesticide formulations was developed. The determination involves on-line hydrolysis of the extracted carbofuran at room temperature with sodium hydroxide. The resulting carbofuran-phenol is coupled with diazotized 4-aminobenzoic acid in order to achieve an appropriate selectivity and sensitivity for the spectrophotometric measurements. The calibration curve is linear over the range 1± 10 mg litre À1 of carbofuran. The proposed method has a detection limit of 0.15 mg litre À1 of carbofuran and a sample frequency of 120 injections per hour. The relative standard deviation of six independent determinations of a sample containing 1 mg litre À1 carbofuran was 0.6%. The suitability of the proposed procedure for the determination of carbofuran in commercial pesticide formulations was studied. The procedure provides results comparable to those obtained by liquid chromatographic analysis.

Flow Injection Spectrophotometric Determination of Propoxur With Diazotized 4-Aminobenzoic Acid

“…[7] Liquid chromatography has been frequently used to separate and determine propoxur. [26][27][28][29][30][31] Downloaded by [University of Chicago Library] at 15: 14 19 November 2014 A more direct method applicable to spectrophotometry would be preferable.…”