Novel and validated spectrophotometric matrix matching method for simple and rapid determination of chromium in oily media

Abstract

N,N'-bis(4-methoxysalicylidene) ethylenediamine is proposed as analytical reagent for the direct determination of chromium in original matrix of liquid oils. The method is based on the complexation of N, N'-bis (4-methoxysalicylidene) ethylenediamine and chromium in n-hexane : acetone (1 : 4) medium and spectrophotometric determination at 355 nm against reagent blank. Complexation of MSE and chromium is completed in 20 seconds at molar ratio 1 : 1. The molar absorptivity and the formation constant of the complex are determined as 9 740 L . mol(-1) . cm(-1) and 3. 6 (+/- 0. 1) x 10(5), respectively. Beer's law is obeyed in range 0. 02 similar to 1. 50 mg . chromium concentration. Limits of detection and quantification of the suggested method were 7. 5 and 25. 1 mu g . kg(-1), respectively. The accuracy and precision of the method was checked by finding mean recovery and relative standard deviation by oil-based chromium standard analysis as 96. 4%+/- 1. 4% and 1. 5 9 0, respectively. The practical applicability of elaborate method was tested using oil-based chromium standard spiked and unspiked corn, sunflower, soybean, olive and canola oils.