Design and Development of a Novel Glucose Biosensor Based on the Ferrocene-Functionalized Fe3O4 Nanoparticles/Carbon Nanotubes/Chitosan Nanocomposite Film Modified Electrode

采用交联法制备了羧基二茂铁功能化Fe3O4纳米粒子（FMC-AFNPs）复合材料，并将该复合纳米材料与多壁碳纳米管（MWNTs）、壳聚糖（CS）及葡萄糖氧化酶（GOD）混合修饰于自制的磁性玻碳基底(MGC)表面，制备了GOD/FMC-AFNPs/MWNTs/CS复合膜生物传感器电极. 实验结果表明，FMC-AFNPs复合材料有效地克服了二茂铁在电极表面的泄漏，且FMC-AFNPs/MWNTs/CS复合膜良好的生物兼容性较大地改善了固定化GOD的生物活性. MWNTs具有良好的导电性和大比表面积，在修饰膜内可作为电子传递“导线”，极大地促进电极的电子传递速率，提高电极的电催化活性和灵敏度. 该电极的葡萄糖检测的线性范围为1.0×10-5 ~ 6.0×10-3 molL-1，检测限为3.2×10-6 mmolL-1（S/N=3），表观米氏常数为5.03×10-3 mmolL-1，且有较好的稳定性和重现性.A novel platform for the fabrication of glucose biosensor was successfully constructed by entrapping glucose oxidase (GOD) in a ferrocene monocarboxylic acid-aminated Fe3O4 magnetic nanoparticles conjugate (FMC-AFNPs)/chitosan (CS)/multiwall carbon nanotubes (MWNTs) nanocomposite. The formation of FMC-AFNPs could effectively prevent the leakage of ferrocene and retain its electrochemical activity. This GOD/FMC-AFNPs/CS/MWNTs matrix provided a biocompatible microenvironment for retaining the native activity of the immobilized GOD. Moreover, the presence of MWNTs enhanced the charge-transport properties of the composite and facilitated electron transfer between the GOD and the electrode for the electrocatalysis of glucose. Under the optimal conditions the designed biosensor to glucose exhibited a wide and useful linear range of 1.0×10-5 to 6.0×10-3 molL-1 with a low detection limit of 3.2×10-6 molL-1（S/N=3）. The value of was 5.03×10-3 molL-1, indicating that the biosensor possesses higher biological affinity to glucose. Furthermore, the biosensor possesses satisfactory stability and good reproducibility.国家863计划资助项目(No. 2012AA022604)、国家自然科学基金（No. 20975021，No. 21275028）、福建省高校产学研科技重点项目(No. 2010Y4003)、福建省自然科学基金资助项目(No. 2010J06011)和福建医科大学博士启动基金（No. 2011BS005）资助作者联系地址：1. 福建医科大学药学院药物分析系，福建 福州 350004；2. 南昌大学高等研究院，江西 南昌 330031Author's Address: 1. Department of Pharmaceutical Analysis of the Fujian Medical University，Fuzhou 350004，China；2. Institute for Advanced Study of Nanchang University，Nanchang 330031，China通讯作者E-mail：[email protected]; [email protected]

Electrocatalytic Activities of Mb/AuNPs/MWNTs/GC Electrode for Hydrogen Peroxide Reduction

采用还原法制备了AuNPs/MWNTs复合材料，并构建了氧化还原蛋白质的固定化和生物传感界面AuNPs/MWNTs/GC电极. 以肌红蛋白（Myoglobin，Mb）为例，研究了固定化蛋白质在AuNPs/MWCNTs/GC电极上的直接电化学. 结果表明，AuNPs/MWCNTs复合材料不仅能有效地促进Mb与电极表面的直接电子转移，而且能很好地保持固定化Mb的生物催化活性. Mb/AuNPs/MWCNTs/GC电极对H2O2具有良好的电催化还原性能，其线性响应范围为1 ~ 138 μmol.L-1，检测下限为0.32 μmol.L-1（S/N=3），并具有较低的米氏常数（0.143 mmol.L-1）. 该电极操作简单，响应迅速，稳定性和重现性好，有望用于蛋白质的固定化及第三代生物传感器的制备.A novel matrix, multiwalled carbon nanotubes supported Au nanoparticles composite nanomaterial (AuNPs/MWNTs), for immobilization of protein and biosensing was designed using a simple and effective one-step in situ synthesis route. Using myoglobin (Mb) as a model, the direct electrochemistry of the immobilized proteins on the AuNPs/MWNTs composite was studied. The results showed that the AuNPs/MWNTs composite can maintain the bioactivity and facilitate the direct electrochemistry of Mb in the Mb/AuNPs/MWNTs/GC electrode. Based on the direct electron transfer of the immobilized Mb, the protein electrode exhibited excellent electrocatalytic activity to the reduction of H2O2 with a linear range of 1 ~ 138 μmol.L-1，low detection limit of 0.32 μmol.L-1 (S/N=3) and a low apparent Kmapp value of 0.143 mmol.L-1. The simple operation, fast response and well reproducibility of the proposed biosensor indicated its promising application in protein immobilization and preparation of the third generation biosensors.国家863计划资助项目(No. 2008AA02Z433)，国家自然科学基金资助项目(No. 20975021，No. 81171668)，福建省高校产学研科技重点项目(No. 2010Y4003)，福建省自然科学基金资助项目(No. 2010J06011)，福建医科大学校重大项目(No. 09ZD013)，福建省教育厅科技项目(No. JA10126，No. JA11110)和福建医科大学博士启动基金（No. 2011BS005）资助作者联系地址：1. 福建医科大学药学院药物分析系，福建 福州 350004； 2. 南昌大学高等研究院，江西 南昌 330031；3. 福建省药品检验所，福建 福州350001Author's Address: 1. Department of Pharmaceutical Analysis of the Fujian Medical University，Fuzhou 350004，China；2. Institute for Advanced Study of Nanchang University，Nanchang 330031，China；3. Fujian Provincial Institute for Drug Control，Fuzhou 350001，China通讯作者E-mail：[email protected]；[email protected]