Direct electrochemistry of glucose oxidase at electrochemically reduced graphene oxide-multiwalled carbon nanotubes hybrid material modified electrode for glucose biosensor

• Published in: Biosensors & bioelectronics Vol. 41; pp. 309 - 315
• Main Authors: Mani, Veerappan, Devadas, Balamurugan, Chen, Shen-Ming
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15.03.2013; Elsevier
• Subjects: Amperometry; Biological and medical sciences; Biosensing Techniques - instrumentation; Biosensors; Biotechnology; Blood Glucose - analysis; Conductometry - instrumentation; Direct electrochemistry; Equipment Design; Equipment Failure Analysis; ERGO–MWCNT hybrid; Fundamental and applied biological sciences. Psychology; Glucose oxidase; Glucose Oxidase - chemistry; Graphite - chemistry; Methods. Procedures. Technologies; Microelectrodes; Nanotubes, Carbon - chemistry; Nanotubes, Carbon - ultrastructure; Oxidation-Reduction; Oxides - chemistry; Practicality; Reproducibility of Results; Sensitivity and Specificity; Various methods and equipments; Amperometry; ERGO–MWCNT hybrid; Glucose oxidase; Direct electrochemistry; Practicality; Enzyme; Hybrid material; Nanotube; Hybrid; Nanostructure; Carbon; ERGO―MWCNT hybrid; Electrodes; Graphene; Biosensor; Electrochemistry; Oxidoreductases
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2012.08.045

Direct electrochemistry of glucose oxidase (GOx) at an electrochemically reduced graphene oxide–multiwalled carbon nanotubes hybrid (ERGO–MWCNT) modified glassy carbon electrode (GCE) has been reported. The π–π stacking interaction operating between the MWCNT and graphene oxide (GO) has been revealed by UV–Vis absorption spectroscopy. GOx was well immobilized onto the ERGO–MWCNT hybrid film, as a result direct electrochemistry of GOx has been achieved. Compared with pristine MWCNT, 2.1 fold higher peak current and very low peak to peak separation (ΔEp) of 26mV were observed at the hybrid film, demonstrating faster electron transfer between GOx and the modified electrode surface. Moreover, the modified film exhibited high electrocatalytic activity towards glucose via reductive detection of oxygen consumption and in the presence of mediator. The proposed biosensor exhibits low detection limit of 4.7μM with wide linear range of 0.01–6.5mM and acquires excellent storage and operational stabilities. The accurate glucose determination in human blood serum and good recoveries achieved in spiked urine samples revealed their great potential in the practical applications. ► Reduced graphene oxide–multi-walled carbon nanotube hybrid. ► Direct electrochemistry of GOx. ► Reductive detection of O2 consumption. ► Amperometric mediated sensing. ► Practicality—blood serum, urine samples.