Centre of Advanced Studies, Faculty of Military Health Sciences, University of Defense, Hradec Kralove, Czech Republic.
Talanta. 2010 Apr 15;81(1-2):621-4. doi: 10.1016/j.talanta.2009.12.052. Epub 2010 Jan 11.
A dipstick for fast assay of nerve agents and organophosphate pesticides was developed. Indicator pH papers were used as detectors. The principle of the assay is based on enzymatic hydrolysis of acetylcholine into acetic acid and choline by acetylcholinesterase. Acidification of the reaction medium due to accumulation of acetic acid was visible. The colour changed from dark red to yellow as the pH indicator recognized pH shift. Presence of an organophosphate pesticide or a nerve agent results in irreversible inhibition of acetylcholinesterase intercepted on the dipstick. The inhibition stops the enzymatic reaction. The inhibition appears as no change of the medium pH. Three compounds were assayed: paraoxon-ethyl as representative organophosphate pesticides and nerve agents sarin and VX. The achieved limit of detection was 5 x 10(-8)M for paraoxon-ethyl and 5 x 10(-9)M for sarin and VX. Dipsticks were found stable for at least one month. Suitability of these dipsticks for routine assay is discussed.
研制了一种快速检测神经毒剂和有机磷农药的检测条。使用指示剂 pH 试纸作为检测器。检测的原理是基于乙酰胆碱酯酶将乙酰胆碱水解为乙酸和胆碱。由于乙酸的积累，反应介质的酸化是可见的。随着 pH 指示剂识别到 pH 变化，颜色从深红色变为黄色。有机磷农药或神经毒剂的存在会导致截留在检测条上的乙酰胆碱酯酶不可逆抑制。抑制停止了酶反应。抑制表现为介质 pH 没有变化。检测了三种化合物：作为代表性有机磷农药的对氧磷乙基和神经毒剂沙林和 VX。对氧磷乙基的检测限达到 5 x 10(-8)M，沙林和 VX 的检测限达到 5 x 10(-9)M。检测条在至少一个月内保持稳定。讨论了这些检测条用于常规检测的适用性。
