基于静电吸附多层膜固定酶的过氧化氢生物传感器的研究

Hydrogen Peroxide Biosensor Based on Enzyme Multilayers through Electrostatic Adsorption

以玻碳电极为基底 ,电聚合 2 ,6 吡啶二甲酸 (PDC) ,使形成一带负电的界面 ,再通过静电吸附自组装一层聚阳离子聚丙烯胺 (PAH) ,用于静电吸附固定辣根过氧化物酶并以此方法固定多层酶膜制备过氧化氢传感器 .探讨了工作电位、介体浓度、pH对电极响应的影响 ,考察了电极的重现性、干扰及使用寿命 .该传感器在H2 O2 浓度 4 6× 10 -6～ 3 5× 10 -3 mol/L范围内有线性响应 ,检出限为 2× 10 -6mol/L .电极在用于实际试样回收率的测定中 。

A hydrogen peroxide biosensor has been prepared, and the procedure is as follows: firstly 2,6-pyridinedicarboxylic acid is electropolymerized onto a glassy carbon electrode to form a negatively charged surface; secondly, the positively charged polyelectrolyte poly(allylamine hydrochloride) (PAH) layer is constructed by the self-assembly technique to immobilize the negatively charged horseradish peroxidase through electrostatic adsorption; lastly, the multi-enzyme layers are fixed by the above methods and the biosensor are constructed. The effects of experimental conditions such as applied potential, mediator concentration and pH values on the electrode performance have been investigated, and the reproducibility, interferences and lifetime of the electrode are also tested. The linear response of detection of the electrode to hydrogen peroxide is in the concentration range of 4 6×10 -6～3 5×10 -3 mol/L with a detection limit of 2×10 -6 mol/L. The electrode was applied to the determination of recoveries of real sample with satisfactory results.