Simultaneous determination of carbendazim and chlorothalonil pesticide residues in peanut oil using excitation-emission matrix fluorescence coupled with three-way calibration method.

Abstract

A novel fluorescence application for simultaneous determination of two common fungicide pesticides (carbendazim and chlorothalonil) in peanut oil is presented. Using the strategy of combining excitation-emission matrix (EEM) fluorescence with three-way calibration methods, the proposed approach successfully achieved quantitative analysis of carbendazim and chlorothalonil pesticide residues in peanut oil, even with highly overlapped spectra. It needs little preparation, using "mathematical separation" instead of "analytical separation" to achieve concentration prediction of target analytes in complex systems. Each analyte was performed using fluorescence spectroscopy after instrument spectral correction and scatter removal. Then the data were modeled with two three-way calibration algorithms, including alternating trilinear decomposition (ATLD) and alternating penalty trilinear decomposition (APTLD). The results indicated that APTLD performed slightly better than ATLD for this system. The carbendazim and chlorothalonil can be recognized simultaneously with the correlation coefficients all above 0.96 between resolved spectra and actual spectra. Satisfactory results have been achieved with the average recoveries (mean ± standard deviation) of carbendazim and chlorothalonil being 100.2 ± 6.7% and 99.7 ± 6.7%, respectively. Moreover, as for carbendazim and chlorothalonil, the sensitivity (SENs) are 1.50 × 102 and 3.80 × 102 mL ng-1, the limits of detection (LODs) are 11 ng mL-1 and 4.3 ng mL-1, the limit of quantitation (LOQ) are 33.33 ng mL-1 and 13.03 ng mL-1, respectively. The above results demonstrated that the proposed method is sensitive, fast and accurate for direct quantitative analysis of multiple pesticide residues in complex matrix such as that of peanut oil.