Sigolaeva Larisa V, Günther Ulrike, Pergushov Dmitry V, Gladyr Snezhana Yu, Kurochkin Ilya N, Schacher Felix H
Department of Chemistry, Lomonosov Moscow State University, 119991, Moscow, Russia.
Macromol Biosci. 2014 Jul;14(7):1039-51. doi: 10.1002/mabi.201300580. Epub 2014 Apr 17.
This work examines the fabrication regime and the properties of polymer-enzyme thin-films adsorbed onto conductive substrates (graphite or gold). The films are formed via two-steps, sequential adsorption of poly(n-butylmethacrylate)-block-poly(N,N-dimethylaminoethyl methacrylate) (PnBMA-b-PDMAEMA) diblock copolymer micelles (1st step of adsorption), followed by the enzyme choline oxidase (ChO) (2nd step of adsorption). The solution properties of both adsorbed components are studied and the pH-dependent step-by-step fabrication of polymer-enzyme biosensor coatings reveals rather drastic differences in their enzymatic activities in dependence on the pH of both adsorption steps. The resulting hybrid thin-films represent highly active biosensors for choline with a low detection limit of 30 nM and a good linearity in a range between 30 nM and 100 μM. The sensitivity is found to be 175 μA mM(-1) cm(-2) and the operational stability of the polymer-enzyme thin-films can be additionally improved via enzyme-to-enzyme crosslinking with glutaraldehyde.
本工作研究了吸附在导电基底（石墨或金）上的聚合物-酶薄膜的制备方式及其性质。这些薄膜通过两步法形成，依次吸附聚（甲基丙烯酸正丁酯）-嵌段-聚（甲基丙烯酸N，N-二甲基氨基乙酯）（PnBMA-b-PDMAEMA）二嵌段共聚物胶束（第一步吸附），随后吸附胆碱氧化酶（ChO）（第二步吸附）。研究了两种吸附成分的溶液性质，并且聚合物-酶生物传感器涂层的pH依赖性逐步制备揭示了其酶活性根据两个吸附步骤的pH值存在相当大的差异。所得的混合薄膜代表了用于胆碱的高活性生物传感器，检测限低至30 nM，在30 nM至100 μM范围内具有良好的线性。灵敏度为175 μA mM⁻¹ cm⁻²，并且聚合物-酶薄膜的操作稳定性可以通过用戊二醛进行酶与酶交联来进一步提高。
