Determination of organophosphate pesticides using an acetylcholinesterase-based biosensor based on a boron-doped diamond electrode modified with gold nanoparticles and carbon spheres
Determination of organophosphate pesticides using an acetylcholinesterase-based biosensor based on a boron-doped diamond electrode modified with gold nanoparticles and carbon spheres
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DOI：
10.1007/s00604-013-1078-4
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发表时间：
2013
影响因子：
5.7
通讯作者：
Min Wei;Gaoying Zeng;Qiyu Lu
中科院分区：
文献类型：
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作者：
Min Wei;Gaoying Zeng;Qiyu Lu
利用有机磷农药对乙酰胆碱酯酶(AChE)活性的抑制作用，研制了一种有机磷农药(OPs)生物传感器。以间苯二酚和甲醛为原料合成了平均直径为500 nm的碳球(CS)，制备了一种纳米复合材料修饰掺硼金刚石(BDD)电极，并在其表面化学生长了一层金纳米粒子(AuNPs)。与裸BDD电极相比，这种新电极的电子转移电阻更低。与不加Au-NPs的电极相比，峰电位负移了42 mV，峰电流增加了55%。这归因于AuNP-CS纳米复合材料具有更大的表面，改善了对AChE的吸附，增强了其活性，并促进了电催化。在最佳条件下，毒死蜱的抑制作用与其浓度在10−11~10−7M范围内的负对数呈线性关系，检出限为1.3 × 10−13M。对甲基对硫磷的抑制作用在10−12~10−6M范围内呈线性关系，检出限为4.9 × 10−13M。该传感器具有良好的精密度和良好的操作稳定性和时间稳定性。图1.首次制备了一种新型的基于乙酰胆碱酯酶的生物传感器，该传感器基于纳米金和碳球修饰的掺硼钻石电极，用于检测有机磷农药。该生物传感器具有较高的灵敏度、较低的检测下限、良好的重现性和较好的稳定性。
We report on a biosensor for organophosphate pesticides (OPs) by exploiting their inhibitory effect on the activity of acetylcholinesterase (AChE). A boron-doped diamond (BDD) electrode was modified with a nanocomposite prepared from carbon spheres (CSs; with an average diameter of 500 nm) that were synthesized from resorcinol and formaldehyde, and then were coated with gold nanoparticles (AuNPs) by chemically growing them of the CSs. Compared to a bare BDD electrode, the electron transfer resistance is lower on this new electrode. Compared to an electrode without Au-NPs, the peak potential is negatively shifted by 42 mV, and the peak current is increased by 55 %. This is ascribed to the larger surface in the AuNP-CS nanocomposite which improves the adsorption of AChE, enhances its activity, and facilitates electrocatalysis. Under optimum conditions, the inhibitory effect of chlorpyrifos is linearly related to the negative log of its concentration in the 10−11to 10−7M range, with a detection limit of 1.3 × 10−13M. For methyl parathion, the inhibition effect is linear in the 10−12to 10−6M range, and the detection limit is 4.9 × 10−13M. The biosensor exhibits good precision and acceptable operational and temporal stability.FigureA novel acetylcholinesterase-based biosensor based on a boron-doped diamond electrode modified with gold nanoparticles and carbon spheres was firstly prepared to detect organophosphate pesticides. This biosensor exhibited higher sensitivity, lower detection limit, good reproducibility and acceptable stability.