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0WGC)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1.0x10^-5~6.0x10^-3mol·L^-1,检测限为3.2×10^-6mmol·L^-1(S/N=3),表观米氏常数为5.03·10^-3mmol·L^-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 Fe304 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 app of 1.0xl0-5 to 6.0x10^-3 mol.L^-1 with a low detection limit of 3.2x10^-6 mol.L^-1(S/N=3). The value of KM was 5.03x10^-3 mol·L^-1, indicating that the biosensor possesses higher biological affinity to glucose. Furthermore, the biosensor possesses satisfactory stability and good reproducibility.