| With the breakthrough of two core techniques of sub-two micron particles chromatographic column and new liquid chromatographic system, liquid chromatography coupled to mass spectrometry (LC-MS) technology is stepping into a brand-new era. Compared with the traditional technology, praticular advantages of faster analytical speed and higher analytical sensitivity for new technology will make itself play an important role in prospective pesticide residue monitoring.In this doctoral paper, five new analytical methods of three pesticide residue systems were developed by rapid resolution liquid chromatography coupled to mass spectrometry technology (RRLC-MS). Optimization and validation were made for four aspects of sample pre-concentration method, separation of chromatography, analysis of mass spectrum and validation of the proposed method.Two analytical methods, SPE/RRLC-UV/MS and SPE-PCD/RRLC-MS, were investigated for the determination of herbicide mefenacet and three photolysis degradation products residues in Songhuajiang River water body and drinking water. In the SPE pre-concentration step, the adsorbent performance of three types of cartridges and the elution capability of four kinds of eluents were investigated for four analytes; in the LC separation step, rapid resolution high throughout LC column, Zorbax RRHT SB-C18 (50 mm×4.6 mm, 1.8μm, Agilent), was used and two elution modes, constant gradent and gradent, were adopted; for the qualitative and the quantitative method, the retention time and two parts of characteristic ions of every analyte were choosed to be qualitative parameters; two quantitative parameters, the peak area of UV chromatogram and mass chromatogram, were confirmed respectively and the mass spectrum fragmentation mode of mefenacet was studied. The research results show that the linear correlation coefficients (r2) of two proposed methods for four analytes are 0.9992～0.9998 and 0.9986～0.9992 respectively, the mean recoveries are 85.6%～101.4% and 78.6%～101.2% with relative standard deviations (RSD) 3.0%～6.9% and 3.2%～9.2%, the limits of detection (LOD) are 0.02μg·L-1 and 0.02 ng·L-1. The testing results for real water samples showed that four analytes were all detected in Songhuajiang River water body and were not detected in drinking water.Two analytical methods, SPE/RRLC-UV/MS and SPE/RRLC-MS/MS, were used for the determination of eleven triazine herbicides residues in Songhuajiang River water body. In the SPE pre-concentration step, the adsorbent performance of multi-walled carbon nanotube material as SPE adsorbent and the elution capability of five kinds of eluents were investigated for eleven analytes; in the LC separation step, rapid resolution high throughout LC column, Zorbax RRHT SB-C18 (50 mm×4.6 mm, 1.8μm, Agilent), was used and the gradent elution mode was adopted; for the qualitative and the quantitative method, the retention time and two parts of characteristic ions of every analyte were choosed to be qualitative parameters; two quantitative parameters, the peak area of UV chromatogram or mass chromatogram, were confirmed respectively and the mass spectrum fragmentation law of eleven analytes was studied. The research results show that the linear correlation coefficients (r2) of two proposed methods for eleven analytes are 0.9992～0.9996 and 0.9930～0.9980 respectively, the mean recoveries are 72.3%～97.8% and 73.0%～98.0% with relative standard deviations (RSD) 3.2%～13.6% and 2.6%～10.8%, the limits of detection (LOD) are 0.04μg·L-1 and 0.04 ng·L-1. The testing results for real water samples showed that only simazine and atrazine of eleven analytes were detected in Songhuajiang River water body and other nine analytes were not detected.MSPD/RRLC-MS/MS method was developed for the determination of nine organophosphrous pesticides residues in fruits and vegetables. The adsorbent performance of multi-walled carbon nanotube material as MSPD adsorbent and the elution capability of four kinds of eluents were investigated for nine analytes; several important parameters affecting LC separation and mass spectrum analysis were optimized; the mass spectrum fragmentation law of nine analytes was studied. The research results show that the linear correlation coefficient (r2) of the proposed method for nine analytes are 0.9942～0.9996, the mean recoveries are 71.2%～102.8% with relative standard deviation (RSD) 2.0%～11.8% , the limit of detection (LOD) is 0.4 ng·L-1. The proposed method was used for the simultaneous determination of these nine analytes residues in eight different fruit and vegetable samples.
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