Integration of polyaniline/poly(acrylic acid) films and redox enzymes on electrode supports:: An in situ electrochemical/surface plasmon resonance study of the bioelectrocatalyzed oxidation of glucose or lactate in the integrated bioelectrocatalytic systems
Integration of polyaniline/poly(acrylic acid) films and redox enzymes on electrode supports:: An in situ electrochemical/surface plasmon resonance study of the bioelectrocatalyzed oxidation of glucose or lactate in the integrated bioelectrocatalytic systems
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DOI：
10.1021/ja012680r
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发表时间：
2002-06-05
影响因子：
15
通讯作者：
Willner, I
中科院分区：
文献类型：
--
作者：
Raitman, OA;Katz, E;Willner, I
苯胺在聚丙烯酸的存在下在Au电极上电聚合得到聚苯胺/聚丙烯酸复合膜，在pH = 7.0的水溶液中表现出可逆的氧化还原功能。原位电化学- spr测量分别用于确定聚苯胺（PAn）氧化至其氧化态（PAn(2+)）和氧化聚合物（PAn(2+)）还原至其还原态（PAn）时聚合物膜的膨胀和收缩动力学。N-6-（2-氨基乙基）-黄素腺苷二核苷酸（氨基- fad， 1）共价附着在复合聚苯胺/聚丙烯酸薄膜的羧基上，然后在功能聚合物上重组无糖葡萄糖氧化酶，产生与电极电接触的葡萄糖氧化酶，具有前所未有的电通信效率：30度下的电子转移周转率接近1000 s（-1）。原位电化学- spr分析用于表征生物材料-聚合物界面的生物电催化功能。随着葡萄糖浓度的升高，生物电催化系统的电流响应增加。同样，体系的SPR光谱也受葡萄糖浓度的控制。葡萄糖浓度控制着膜组成物中PAn/PAn（2+）的稳态浓度比。因此，电化学氧化后测得的膜的SPR谱由低葡萄糖浓度下氧化PAn（2+）的典型谱转变为高葡萄糖浓度下还原PAn的谱特征。同样，聚苯胺/聚丙烯酸薄膜作为NADH氧化的电催化剂。因此，通过N-6-（2-氨基乙基）- β -烟酰胺腺嘌呤二核苷酸（氨基-NAD(+), 2）的共价附着在聚合物薄膜上，在电极上构建了一个集成的生物电催化组装体，并以戊二醛作为交联剂在乳酸脱氢酶和与聚合物相关的NAD(+)-辅因子单元之间形成了一个二维交联的亲和复合物。原位电化学- spr测量用于表征系统的生物电催化功能。系统的安培响应随着乳酸浓度的升高而增加，生物催化剂和电极之间的电子转移周转率估计为350 s（-1）。由于PAn（2+）氧化乳酸生物催化氧化产生的NADH单元，膜中PAn/PAn（2+）稳态比受乳酸浓度控制，因此电化学氧化膜测得的SPR谱与PAn（2+）谱相似。在低乳酸浓度下，SPR谱与高浓度乳酸时的PAn谱相似。
Electropolymerization of aniline in the presence of poly(acrylic acid) on Au electrodes yields a polyaniline/poly(acrylic acid) composite film, exhibiting reversible redox functions in aqueous solutions at pH = 7.0. In situ electrochemical-SPR measurements are used to identify the dynamics of swelling and shrinking of the polymer film upon the oxidation of the polyaniline (PAn) to its oxidized state (PAn(2+)) and the reduction of the oxidized polymer (PAn(2+)) back to its reduced state (PAn), respectively. Covalent attachment of N-6-(2-aminoethyl)-flavin adenin dinucleotide (amino-FAD, 1) to the carboxylic groups of the composite polyaniline/poly(acrylic acid) film followed by the reconstitution of apoglucose oxidase on the functional polymer yields an electrically contacted glucose oxidase of unprecedented electrical communication efficiency with the electrode: electron-transfer turnover rate similar to1000 s(-1) at 30 degreesC. In situ electrochemical-SPR analyses are used to characterize the bioelectrocatalytic functions of the biomaterial-polymer interface. The current responses of the bioelectrocatalytic system increase as the glucose concentrations are elevated. Similarly, the SPR spectra of the system are controlled by the concentration of glucose. The glucose concentration controls the steady-state concentration ratio of PAn/PAn(2+) in the film composition. Therefore, the SPR spectrum of the film measured upon its electrochemical oxidation is shifted from the spectrum typical for the oxidized PAn(2+) at low glucose concentration to the spectrum characteristic of the reduced PAn at high glucose concentration. Similarly, the polyaniline/poly(acrylic acid) film acts as an electrocatalyst for the oxidation of NADH. Accordingly, an integrated bioelectrocatalytic assembly was constructed on the electrode by the covalent attachment of N-6-(2-aminoethyl)-beta-nicotinamide adenine dinucleotide (amino-NAD(+), 2) to the polymer film, and the two-dimensional cross-linking of an affinity complex formed between lactate dehydrogenase and the NAD(+)-cofactor units associated with the polymer using glutaric dialdehyde as a cross-linker. In situ electrochemical-SPR measurements are used to characterize the bioelectrocatalytic functions of the system. The amperometric responses of the system increase as the concentrations of lactate are elevated, and an electron-transfer turnover rate of 350 s(-1) between the biocatalyst and the electrode is estimated. As the PAn(2+) oxidizes the NADH units generated by the biocatalyzed oxidation of lactate, the PAn/PAn(2+) steady-state ratio in the film is controlled by the concentration of lactate, Accordingly, the SPR spectrum measured upon electrochemical oxidation of the film is similar to the spectrum of PAn(2+). at low lactate concentration, whereas the SPR spectrum resembles that of PAn at high concentrations of lactate.