Simultaneous Spectrophotometric Quantification of Crystal Violet and Malachite Green in Aqueous Samples: Combination of Multivariate Calibration Method and Solid Phase Extraction Based on Sodium Dodecyl Sulfate (SDS) Grafted Chitosan Nano-composite

摘要

A simple solid phase extraction (SPE) based on sodium dodecyl sulfate grafted chitosan nanocomposite was developed for simultaneous spectrophotometric determination of crystal violet (CV) and malachite green (MG) content water samples. For the data analysis of the overlapped spectra of two dyes, the partial least square regression (PLS) has been utilized. The new synthesized sorbent was characterized by Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and Energy dispersive X-ray spectroscopy (EDX). The results showed the SDS was successfully cross-linked with the chitosan. Various parameters affecting simultaneous extraction of analytes, such as pH of sample solution, sample flow rate and the volume and flow rate of eluent were optimized by central composite design and response surface methodology (RSM). Figures of merit consist of sensitivity, analytical sensitivity, limits of detection (LOD) and limit of quantitation (LOQ) were found to be 0.1879 ng/ml, 595.4409, 0.0632 and 0.1895 ng/ml and 0.1895 for CV and 0.0464, 595.4409, 0.1246 and 0.3738 ng/ml for MG, respectively. The correlation coefficient of 0.9990 and 0.9991 were achieved for CV and MG, respectively. Net analyte signal (NAS) was proposed to estimate the preconcentration factor for the analytes in mixtures.