A rapid, eco-friendly, and reliable microplate method for determination of Cr(VI)

In the present work, the reaction of Cr(VI) with 1,5-diphenylcarbazide in microplates (enzyme-linked immunosorbent assay microtiter plate) and a subsequent determination in a plate reader at 540 nm were performed. The final volume utilized for each determination was 200 μL, and the cost and waste were reduced for hexavalent chromium [Cr(VI)] quantification. The use of microplates allowed for the analysis of a large number of samples, reducing analysis time. No statistically significant differences were observed between the results obtained in the analysis of Cr(VI) in real samples by the conventional procedure and by the proposed methodology in this work (analysis of variance, P < 0.05). Employing the proposed method, the limit of detection (5.95 μg L−1) of Cr(VI) was lower than that obtained with the traditional method. Thus, the analytical results obtained suggest that this methodology is faster, more economical, and more environmentally friendly than the traditional method.