Simultaneous Screening of 733 Pesticide Residues in Fruits and Vegetables by a GC/LC-Q-TOFMS Combination Technique

In this paper,we report the construction of two accurate mass databases and the development of a combination detection method that simultaneously screens for 733 pesticide and chemical contaminant multi-residues via high-throughput liquid chromatography(LC)-and gas chromatography(GC)-quadru pole-time-of-flight mass spectrometry(Q-TOFMS).This work demonstrates that electronic mass spectral standards may replace chemical-source standard materials as references through one sample preparation and the combination of GC/LC-Q-TOFMS screening.This cutting-edge technique has also replaced multiresidue determination using targeted detection with non-targeted screening.The pesticide residue types,sensitivity,recovery,and reproducibility of this combination technique are evaluated in eight fruit and vegetable matrices.This technique shows three advantages:①In comparison with the discovery capability of a single technique,the combination technique shows an improvement of 51.1%(GC-QTOFMS)and 39.6%(LC-Q-TOFMS),respectively;②the combination technique can satisfy a screening limit lower than 10μg·kg^-1 and meet the requirements of“uniform standards,”although some of the pesticide residues could be optimized to further improve screening sensitivity;③over 488 pesticides with recoveries between 60%-120%and relative standard deviation(RSD)<20%at a spiked level of 10μg·kg^-1 were detected with the combination technique in eight different matrices.From 2012 to 2017,this combination technique was applied in an investigation to screen pesticide residues from 1384 sampling locations for 38138 batched samples covering 18 categories and 134 types of fruits and vegetables obtained from across the mainland of China.After statistical analysis,533 pesticides in 115891 determinations were detected,and the regularity of pesticides in the fruits and vegetables sold on the Chinese market was shown.

Chromatographic fingerprint analysis and quantitative evaluate the rhizomes of Alpinia officinarum Hance(lesser galangal)

The rhizome of Alpinia officinarum Hance is a well-known traditional Chinese medicine(TCM)and has been widely used for the remedy of gastrointestinal diseases.In the present study,a simple and rapid HPLC-DAD was developed for the quality control of the rhizomes of A.officinarum.Its chemical fingerprint was established using raw material of 15 different origins in China.Similarity analysis(SA)and hierarchical clusting analysis(HCA)were applied to select the qualitative markers.Principal components analysis(PCA)was conducted to select the quantitative markers of the rhizomes of A.officinarum samples from different origins.The constituents were confirmed by(+)electrospray ionization LC-MS.12 constituents were selected as common peaks and 10 of them were confirmed by(+)electrospray ionization LC-MS.Six bioactive constituents including DPHA,galangin flavanone,galangin,galangin 3-methylether,DPHB and DPHC were simultaneous determination by using the HPLC-DAD analysis.The developed method was able to determine the bioactive components with excellent resolution,precision and recovery.The results indicated that chromatographic fingerprint combination with multi-components determination method is suitable for quality assessment of the rhizomes of A.officinarum.