In this study, we have established rapid and sensitive analytical method using LC-MS/MS for residue analysis of mancozeb and its metabolite, ETU, in mandarin. For mancozeb analysis, the samples were extracted with an aqueous EDTA/methanol mixture, and the sodium salt form of the analyte was derivatised with iodomethane prior to clean up using a C18 SPE cartridge. ETU was extracted with dichlomethane, using ETU-D4 as the internal standard. Used analytic LC column was the Capcellpak C18 (5 um, 2 x 50 mm) for Mancozeb, and Unison UK-C8 (3 um, 2 x 75 mm) for ETU. Mancozeb and ETU were quantitatively analyzed in positive electrospray ionization mode, using ion transitions of m/z 241 > 134.1 and 107 > 48.2, respectively. The calibration curves of mancozeb (as the methylated derivative) and ETU were linear over the range from 0.2 to 10 ug/kg for mancozeb, and 2.5 to 100 ug/kg for ETU. The limit of quantification (LOQ) was 0.01 mg/kg in mancozeb and its metabolite, ETU, respectively. Average recoveries at the LOQ were at least over 90%, and CV (%) was within 10%. Analytical method of mancozeb and ETU established in this study could reduce the time required for sample preparation and pre-treatment steps by simplifying. It is considered that this is suitable analytical method for mancozeb and its metabolite, ETU in fruit commodities, as satisfied in reproducibility and precision, etc.

Residue analysis of mancozeb and its metabolites, ETU, in mandarin using LC-MS/MS

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.