Freeman J A, Johnson J V, Yost R A, Kuehl D W
Chemistry Department, University of Florida, Gainesville 32611.
Anal Chem. 1994 Jun 1;66(11):1902-10. doi: 10.1021/ac00083a021.
A promising instrumental technique has been investigated to rapidly screen complex environmental samples for chemical contaminants having the propensity to covalently bond to biomacromolecules such as DNA. Radical molecular ions of pyridine, a model compound for nucleophilic bases of DNA, were mass-selected and allowed to react with electrophilic environmental contaminants in the collision cell of a triple quadrupole mass spectrometer. Analytes were introduced into the collision cell via a gas chromatographic column. Reactive chemicals are then characterized by scanning Q3 to identify associative reaction products. A good qualitative correlation was observed for the gas-phase reactivity of a series of electrophilic reagents with both their alkylating reactivity in solution (4-(4-nitrobenzyl)pyridine) and AMES test mutagenicity which had been previously published. Femtomole limits of detection for specific associative reaction products were demonstrated. Gas-phase reactions of ions of environmental contaminants (introduced into the source) with neutral pyridine (in the collision cell) were also investigated. Reactions of the radical molecular ion of the allyl reagents with neutral pyridine were similar to results from the mass-selected reaction of the pyridine radical molecular ion with neutral allylic reagents.
人们研究了一种很有前景的仪器技术，用于快速筛选复杂环境样品中具有与生物大分子（如DNA）共价结合倾向的化学污染物。吡啶的自由基分子离子作为DNA亲核碱基的模型化合物，经质量选择后，在三重四极杆质谱仪的碰撞池中与亲电环境污染物发生反应。分析物通过气相色谱柱引入碰撞池。然后通过扫描Q3来鉴定缔合反应产物，从而对反应性化学物质进行表征。对于一系列亲电试剂的气相反应性，与它们在溶液中的烷基化反应性（4-(4-硝基苄基)吡啶）以及先前发表的AMES试验致突变性之间，观察到了良好的定性相关性。证明了特定缔合反应产物的飞摩尔检测限。还研究了环境污染物离子（引入离子源）与中性吡啶（在碰撞池中）的气相反应。烯丙基试剂的自由基分子离子与中性吡啶的反应，类似于吡啶自由基分子离子与中性烯丙基试剂的质量选择反应结果。
