Sheridan R S, Meola J R
New York State Department of Agriculture and Markets, Food Laboratory, Albany 12235, USA.
J AOAC Int. 1999 Jul-Aug;82(4):982-90.
A method for detection, quantitation, and confirmation of more than 100 pesticides by gas chromatography (GC) with ion trap mass spectrometry (MS/MS) has been developed. The sensitivity of this method for many analytes is equal to or lower than those of selective GC detectors such as flame photometric detectors and electrolytic conductivity detectors. Using MS/MS, very low detection limits and good confirmation (1 precursor ion and 2 or more product ions) are achieved simultaneously. The entire list of pesticides is screened with 2 injections per sample. Samples are introduced onto the column by a temperature-programmed cold injection to maximize response. Each pesticide is run with its own unique set of parameters, which fragment the compound, retaining only the precursor ion. This ion is then refragmented to create a product spectrum. The selectivity of MS/MS gives a very clean spectrum, making compound identification and confirmation clear, even with a relatively dirty food matrix. If care is taken to maintain the injection port and guard column, this method can reliably identify and confirm more than 100 pesticides at the low parts-per-billion range.
已开发出一种通过气相色谱（GC）与离子阱质谱（MS/MS）联用检测、定量和确证100多种农药的方法。该方法对许多分析物的灵敏度等于或低于火焰光度检测器和电解电导率检测器等选择性气相色谱检测器。使用MS/MS可同时实现极低的检测限和良好的确证效果（1个母离子和2个或更多子离子）。每个样品通过2次进样对整个农药列表进行筛查。通过程序升温冷进样将样品引入色谱柱，以最大化响应。每种农药都以其自身独特的参数集运行，这些参数会使化合物裂解，只保留母离子。然后该离子再裂解以产生产物谱。MS/MS的选择性产生非常纯净的谱图，即使在相对复杂的食品基质中，也能清晰地进行化合物鉴定和确证。如果注意维护进样口和保护柱，该方法能够可靠地在十亿分之几的低浓度范围内鉴定和确证100多种农药。
