title: Glucose biosensor based on covalent immobilization of enzyme in sol-gel composite film combined with Prussian blue/carbon nanotubes hybrid.
abstract: A novel electrochemical glucose biosensor was developed based on in situ covalent immobilization of glucose oxidase (GOx) by one-pot chitosan (CS)-incorporated sol-gel process in the presence of Prussian blue deposited multi-walled carbon nanotubes hybrids (PB/MWNTs) using 3-isocyanatopropyltriethoxysilane (ICPTES) as both a sol-gel precursor and a covalent coupling agent for GOx and CS. The electrode modified with the PB/MWNTs-GOx-CS-ICPTES sol-gel composite film showed good electrical conductivity and effective low-potential electron transfer mediation toward H2O2 reduction attributed to the incorporation of PB/MWNTs. The biosensor exhibited a linear response to glucose in the concentration range from 2.5×10(-5) to 1.3×10(-3) M with a correlation coefficient of 0.9998, a detection limit of 7.5×10(-6) M, a low response time (10s ), good sensitivity and high anti-interference ability. Compared with the control biosensor based on the traditional tetraethoxysilane derived sol-gel composite film, the biosensor showed a similarly small apparent Michaelis-Menten constant of 3.67 mM but much higher electrochemical and biosensing stability.
authors.affiliation: Nanomedicine and Biosensor Laboratory, School of Sciences, State Key Laboratory of Urban Water Resources and Environment, Harbin Institute of Technology, Harbin 150001, PR China.
authors.forename: Guanglei
authors.initials: G
authors.lastname: Fu
authors.forename: Xiuli
authors.initials: X
authors.lastname: Yue
authors.forename: Zhifei
authors.initials: Z
authors.lastname: Dai
mesh_terms: D015374:Biosensing Techniques; D048271:Chitosan / Q000737:chemistry; D004563:Electrochemistry; D004800:Enzymes, Immobilized / Q000737:chemistry; D005295:Ferrocyanides / Q000737:chemistry; D005947:Glucose / Q000737:chemistry / Q000302:isolation & purification*; D005949:Glucose Oxidase / Q000737:chemistry; D037742:Nanotubes, Carbon / Q000737:chemistry*
chemical_list: D004800:Enzymes, Immobilized; D005295:Ferrocyanides; D037742:Nanotubes, Carbon; D048271:Chitosan; D005949:Glucose Oxidase; D005947:Glucose; C000170:ferric ferrocyanide