A rapid method for measurement of nickel and chromium at trace level in aqueous samples

Abstract

A rapid, simple and portable technique to measure Ni(II) and Cr(VI) at trace level in aqueous samples has been proposed. Colored spots were developed by interacting micro-liter drops of metal solutions with suitable reagents on TLC plates. Soon after, TLC having spots was scanned to import the image into the computer. Color densities of spots were calculated with the help of homemade software. Simple regression was practiced on calibration between standards' concentrations and their color densities. For both metals, correlation coefficients were approaching to one, which pointed out a good correlation between color densities and corresponding analyte concentrations. Real samples from electroplating unit were analyzed with the present and conventional spectrophotometric method (employed as reference), and the results were compared to evaluate the pertinence of the proposed technique in the real analysis. © 2011, Sociedad Química de México.