A bienzyme channeling glucose sensor with a wide concentration range based on co-entrapment of enzymes in SBA-15 mesopores.
A novel bienzyme-channeling sensor was constructed by entrapping glucose oxidase (GOD) and horseradish peroxidase (HRP) in the mesopores of well-ordered hexagonal mesoporous silica structures (SBA-15). The SBA-15 mesoporous materials accelerated the electron transfer between the entrapped HRP and electrode. Both HRP and GOD retained their catalytic activities in the bienzyme-entrapped SBA-15 film. In presence of glucose the enzymatic reaction of GOD-glucose-dissolved oxygen system generated hydrogen peroxide in the bienzyme-entrapped mesopores, which was immediately reduced at -0.40 V by an electrocatalytic reaction with the HRP entrapped in the same mesopore to lead to a sensitive and fast amperometric response. Thus the bienzyme channeling could be used for the detection of glucose with excellent performance without the addition of any mediator. Optimization of the experimental parameters was performed with regard to pH, operating potential and temperature. The detection limit was down to 2.7 x 10(-7)M with a very wide linear range from 3.0 x 10(-6) to 3.4 x 10(-2)M. The constructed bienzyme channeling provided a strategy for amperometric detection of oxidase substrates by co-entrapping the corresponding oxidase and HRP in the mesoporous materials.
Jiangsu Key Laboratory of Biofunctional Materials, College of Chemistry and Environmental Science, Nanjing Normal University, Nanjing, PR China. daizhihuii@njnu.edu.cn
Zhihui
Z
Dai
Jianchun
J
Bao
Xiaodi
X
Yang
Huangxian
H
Ju
D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004800:Enzymes, Immobilized / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005947:Glucose / Q000032:analysis*; D005949:Glucose Oxidase / Q000737:chemistry*; D006735:Horseradish Peroxidase / Q000737:chemistry*; D016062:Porosity; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide / Q000737:chemistry*
D004800:Enzymes, Immobilized; C509969:SBA-15; D012822:Silicon Dioxide; D005949:Glucose Oxidase; D006735:Horseradish Peroxidase; D005947:Glucose