Stabilization of maneb group by ethylenediamine and direct-determination by liquid chromatography tandem mass spectrometry

A rapid, low-cost, and selective method for simultaneous and direct determination of maneb group residues (containing ethylenebis and propylenebis dithiocarbamates) in fruit by liquid chromatography coupled to tandem mass spectrometry was developed and validated in the current study. The results showed the maneb group could be melt and stabilized by 5 v% ethylenediamine for 60 days keeping in conventional refrigerators, in which a stable and ionizable pentadentate ligand complex was considered to be formed by the bidentate diamine and sulfhydryl followed by Density Functional Theory calculation. The validated method showed a sensitive quantification limits (0.03 mg/kg), a steady recovery (82.1%-91.0%) and an excellent precision (2.7%-4.3% RSD). This method is applied to analyze fruit samples and achieved satisfactory results. Therefore, this method can be proposed as a robust analytical method of maneb group in fruit, and can be adapted to detect other compounds with sulfhydryl group.

Automated summary

A rapid, low-cost, and selective liquid chromatography tandem mass spectrometry method was developed and validated for simultaneous determination of maneb group residues in fruit. The validated method showed sensitive quantification limits, steady recovery, and excellent precision. This method was successfully applied to analyze fruit samples and achieved satisfactory results.