Biocompatible hybrid film of β-cyclodextrin and ionic liquids: A novel platform for electrochemical biosensing

• Published in: Sensors and actuators. B, Chemical Vol. 155; no. 2; pp. 632 - 638
• Main Authors: Cao, Anping, Ai, Huihui, Ding, Yonglan, Dai, Chunyan, Fei, Junjie
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 20.07.2011
• Subjects: Biosensors; Direct electrochemistry; Horseradish peroxidase; Ionic liquids; Quercetin; β-Cyclodextrin; PBS; HRP; GCE; Horseradish peroxidase; EIS; LSV; ILs; β-Cyclodextrin; β-CD; CDs; CV; Quercetin; Ionic liquids; SEM; BMIMBF 4; Direct electrochemistry; Biosensors
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2011.01.022

A novel electrochemical biosensing platform was developed based on the modification of biocompatible hybrid film of β-cyclodextrin (β-CD) and ionic liquids (ILs), 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF 4) onto glass carbon electrode (GCE). Then an unmediated biosensor was successfully prepared by immobilizing the horseradish peroxidase (HRP) into the β-CD/ILs composite film. β-CD could provide a biocompatible microenvironment for HRP, and ILs could accelerate the electron transfer between HRP and the electrode. Results showed that the HRP entrapped in the β-CD/ILs film could maintain its native structure and the direct electrochemistry of HRP were facilely achieved. A couple of well-defined redox peaks of HRP were observed at about −0.32 V (vs. SCE), corresponding to the protein heme Fe(III)/Fe(II) redox couples. The electrocatalysis of this biosensor to both quercetin and hydrogen peroxide was characterized. The biosensor exhibited a low operating potential (−0.05 V vs. SCE), fast amperometric response, high sensitivity, good selectivity and sub-micromolar limit of detection.