title: Enzymes immobilized on amine-terminated ionic liquid-functionalized carbon nanotube for hydrogen peroxide determination.
abstract: We report on a new approach for the electrochemical detection of hydrogen peroxide (H2O2) based on Cytochrome C (Cyt c) immobilized ionic liquid (IL)-functionalized multi-walled carbon nanotubes (MWCNTs) modified glass carbon electrode (GCE). Functionalization of multi-walled carbon nanotube with amine-terminated ionic liquid materials was characterized using fourier transform infrared spectroscopy (FTIR), UV-vis spectra, and electrochemical impedance spectroscopy (EIS), and the results showed that the covalent modification of MWCNTs with ILs exhibited a high surface area for enzyme immobilization and provided a good microenvironment for Cyt c to retain its bioelectrocatalytic activity toward H2O2. Amperometry was used to evaluate the catalytic activity of the cyt c towards H2O2. The proposed biosensor exhibited a wide linear response range nearly 4 orders of magnitude of H2O2 (4.0 × 10(-8)M-1.0 × 10(-4)M) with a good linearity (0.9980) and a low detection limit of 1.3 × 10(-8)M (based on S/N=3). Furthermore, the biosensor also displays some other excellent characteristics such as high selectivity, good reproducibility and long-term stability. Thus, the biosensor constructed in this study has great potential for detecting H2O2 in the complex biosystems.
authors.affiliation: Key Laboratory of Bioelectrochemistry & Enviromental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, No. 967 Anning East Road, Lanzhou, Gansu 730070, PR China. liuxh@nwnu.edu.cn
authors.forename: Xiuhui
authors.initials: X
authors.lastname: Liu
authors.forename: Caihong
authors.initials: C
authors.lastname: Bu
authors.forename: Zhihan
authors.initials: Z
authors.lastname: Nan
authors.forename: Lichun
authors.initials: L
authors.lastname: Zheng
authors.forename: Yu
authors.initials: Y
authors.lastname: Qiu
authors.forename: Xiaoquan
authors.initials: X
authors.lastname: Lu
mesh_terms: D000588:Amines / Q000737:chemistry*; D045304:Cytochromes c / Q000378:metabolism; D004800:Enzymes, Immobilized / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000032:analysis*; D052578:Ionic Liquids / Q000737:chemistry*; D037742:Nanotubes, Carbon
chemical_list: D000588:Amines; D004800:Enzymes, Immobilized; D052578:Ionic Liquids; D037742:Nanotubes, Carbon; D045304:Cytochromes c; D006861:Hydrogen Peroxide