The determination of pesticides in fruits and vegetables has been simplified by a new sample preparation method, QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe), and published recently as AOAC Method 2007.01.1 The sample preparation is shortened by using a single step buffered acetonitrile (MeCN) extraction and liquid-liquid partitioning from water in the sample by salting out with so...

A simple and high-throughput screening method for the analysis of 136 pesticides in avocado ( Persea americana ) by LC-(+)-ESI-MS/MS and GC-MS/MS is presented. A modified QuEChERS sample preparation method was developed to improve the extraction recovery of highly lipophilic pesticides. Extracts from minced avocados after acetonitrile (MeCN) extraction were directly injected to LC-MS/MS, wherea...

This paper presents the validation of a modified QuEChERS method in four matrices - green tea, red tea, black tea and chamomile. The experiments were carried out using blank samples spiked with a solution of 86 pesticides (insecticides, fungicides and herbicides) at four levels - 10, 25, 50 and 100 μg/kg. The samples were extracted according to the citrate QuEChERS protocol; however, to reduce ...

A fast gas chromatography coupled with mass spectrometry (GC-MS) using large volume injection with programmed temperature vaporizer in solvent vent mode (PTV-LVI-SV) was developed for the trace determination of multiple pesticide residues in traditional Chinese medicines (TCMs). Experimental conditions of PTV-LVI-SV injection were optimized by central composite design. The optimized result was ...

A rapid method using programmed temperature vaporiser injection-low-pressure gas chromatography-high-resolution time-of-flight mass spectrometry (PTV-LP-GC-HR-TOF-MS) for the analysis of multiple pesticide residues in fruit-based baby food was developed. The fast and inexpensive buffered QuEChERS (quick, easy, cheap, effective, rugged, and safe) extraction method and "conventional" approach tha...

In this paper, a novel method of QuEChERS-based extraction coupled with high-performance liquid chromatography has been developed for the simultaneous determination of ursolic acid (UA) and oleanolic acid (OA) in guava leaves. The QuEChERS-based extraction parameters, including the amount of added salt, vortex-assisted extraction time, and absorbent amount, and the chromatographic conditions we...

background: the present study was the first attempt for determination and measurement of pesticide residues in tomatoes used in salad production plants in isfahan, central iran. methods: a multiresidue method based on modified quechers (quick, easy, cheap, effective, rugged and safe) sample preparation, followed by gas chromatography mass spectrometry (gc–ms) was developed and validated for the...

in this study, residues of imidacloprid (confidor) were measured in greenhouse cucumbers in mazandaran province, iran. confidor 200 sl was applied at the recommended rate (30.0 g ai ha-1) and its double (60.0 g ai ha-1). samples were collected at 1 h to 21 days after application and analyzed to determine the content and dissipation rate of imidacloprid. . analysis was carried out by the quecher...

Background: Green chemistry focuses on an efficient extraction strategy for pesticides from agricultural and environmental samples. QuEChERS (quick, easy, cheap, effective, rugged, and safe) method is used primarily, in the extraction of pesticides from food matrices. Certain modifications in the approach lead to better sensitivity and efficient extraction. This paper describes an analytical ap...