College of Water Sciences, Beijing Normal University, Beijing 100875, China.
J Environ Sci (China). 2012;24(5):956-62. doi: 10.1016/s1001-0742(11)60864-4.
An amperometric biosensor based on screen-printed electrodes (SPEs) was developed for the determination of organophosphorus pesticides in water samples. The extent of acetylcholinesterase (AChE) deactivation was determined and quantified for pesticide concentrations in water samples. An enzyme immobilization adsorption procedure and polyacrylamide gel matrix polymerization were used for fabrication of the biosensor, with minimal losses in enzyme activity. The optimal conditions for enzyme catalytic reaction on the SPEs surfaces were acetylthiocholine chloride (ATChCl) concentration of 5 mmol/L, pH 7 and reaction time of 4 min. The detection limits for three organophosphorus pesticides (dichlorvos, monocrotophs and parathion) were in the range of 4 to 7 microg/L when an AChE amount of 0.1 U was used for immobilization.
基于丝网印刷电极的电流型生物传感器被开发出来，用于测定水样中的有机磷农药。通过测定和定量水样中农药对乙酰胆碱酯酶（AChE）的失活程度来实现。采用酶固定化吸附和聚丙烯酰胺凝胶基质聚合的方法来制备生物传感器，酶活性损失最小。在 SPE 表面上进行酶催化反应的最佳条件为：乙酰硫代胆碱氯（ATChCl）浓度为 5mmol/L，pH 值为 7，反应时间为 4min。当使用 0.1U 的 AChE 进行固定化时，三种有机磷农药（敌敌畏、乐果和对硫磷）的检测限在 4 到 7μg/L 范围内。
