Determination Of Multi-residue Pesticides In Fruits Juices By QuEChERS Cleanup And Gas Chromatography-tandem Mass Spectrometry

Fruit juices win the favor of customers because it is rich in nutrients. China is a large country of fruit production. The fruit juices which are processed by these raw materials not only meet domestic needs, but also export to other countries and regions. During the fruits in process, various pesticides are used to prevent insect and disease, which lead to multi-pesticide residue in juice. In recent years, with the development of science and technology, many countries increase the requirement for items of pesticide residues of the fruit juice that should be detected. And the maximum residue limits significantly reduced. Develop rapid, easy and accurate juice pesticide residue detection technology is the important technical support to control the pesticide residues in juices.Sample pretreatment is the most critical part of the pesticide residues determination.it determines the accuracy and sensitivity of the methods. QuEChERS method is quick, easy, cheap, effective, rugged and safe technique, and Since this technique was proposed it was main used in the pesticide residues of fruits and vegetables.This paper is aimed at the problem of pesticide residues in fruit juices, 90 pesticides were selected as the detection targets, the main content and result were as follows:(1)In this study, an analysis method was developed for determination of 90 pesticides by gas chromatography-mass spectrometry. The instrument parameters were optimized. Under the selected condition ,the chromatographic peaks were sharp and symmetrical, and the result of separation is good.(2)In this study, the factors that influence the experimental result were optimized, such as the extract solvent, the water absorbent, and the dispersive sorbent, and the water absorbent is used for equalizing the response enhancement for calibration standards and sample extracts, a preparation method that extracted by acetonitrile, an hydrated by anhydrous, and cleaned up by PSA and C18 was established.(3) A GC/MS method combined with the QuEChERS for determination the Multi-residue Pesticides in fruit juices was Developed. The precision accuracy and sensitivity was investigated. The result as follows: the mean recoveries of 89 pesticides were in the range of 70.3%~119.2%, the relative standard deviation were from3.4% to 15.6%, the limit of determination is lower than 10μg/kg, the limit of quantity is lower than 20μg/kg. This method was meeting the requirement of the determination of Multi-residue Pesticides in fruit juices, and was applied to more kinds of fruit juices and the application range was extended.