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JA0017
来源:Journal Of Agricultural and Food Chemistry | 作者:HONGXIA GUAN | 发布时间: 2147天前 | 1994 次浏览 | 分享到:
Simple and rapid methods for the analysis of pesticides in produce samples have been developed. The current study involves analysis of nonpolar and polar pesticides using GC-ECD and GC-NPD, respectively. The nonpolar pesticides were extracted using disposable pipette extraction (DPX) following a preliminary acetone extraction based on the Luke method. Recoveries of the fortified pesticides ranged between 70.5 and 110.0%, with relative standard deviations (% RSD) below 10% for most target analytes. From calibration plots, the limits of detection (LOD) were determined to be 0.99. A micro-Luke method was adapted and used for the analysis of polar pesticides, which greatly reduces the
volumes of solvent and time for sample preparation. This new method of analysis, combining DPX and micro-Luke, was compared directly with the modified Luke method for analysis of pesticides in produce samples over a 9 week period. This study validates the suitability for routine analysis of pesticides in acetone extract of fruits and vegetables using the proposed DPX and micro-Luke method
1 Introduction
Regulatory and public concern over pesticide residues in fruits and vegetables has been increasing due to potential health hazards. Measuring trace levels of pesticide residues in the presence of large amounts of sample matrix components that occur naturally is a challenging task. There is growing interest in developing simple, rapid, cost-effective, and reliable analytical methods to ensure that levels of toxic pesticides incurred in produce are below tolerance levels. Sample preparation is the first step in the analysis. Achieving accurate and precise results for the analysis of pesticides in complex matrices such as food depends largely on the extraction and cleanup methods that are employed. Many methods have been reported for the extraction of pesticides from fruits and vegetables (1-8). Perhaps the two most widely employed organic solvents used for sample extraction are acetone, which is used in the Luke method (9), and acetonitrile, which is used in the QuEChERS method (which stands for quick, easy, cheap, effective, rugged, and safe) (10-13). Due to its reliability, the Luke method has been employed for monitoring of pesticides in fruits and vegetables in approximately 80% of the FDA pesticide residue analyses in the 1980s (9). The Luke method is still the accepted residue analysis method in many,....

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