Ratiometric electrochemical glucose biosensor based on GOD/AuNPs/Cu-BTC MOFs/macroporous carbon integrated electrode

• Published in: Sensors and actuators. B, Chemical Chemical, 2018-03, Vol.257, p.792-799
• Main Authors: Song, Yonghai, Xu, Mengli, Gong, Coucong, Shen, Yuan, Wang, Linyu, Xie, Yi, Wang, Li
• Format: Article
• Language: English
• Subjects: AuNPs; Biosensors; Carbon; Chemical sensors; Copper; Cu-BTC MOFs; Current density; Electrodes; Glucose; Glucose oxidase; Gold; Macroporous carbon; Metal-organic frameworks; Ratiometric electrochemical biosensor; Reduction; Reproducibility; Scanning electron microscopy; Trimesic acid
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2017.11.004

[Display omitted] •A novel AuNPs/Cu-BTC MOFs/3D-KSCs integrated electrode was prepared.•The Cu-BTC MOFs catalyzed glucose oxidation as reference signal.•The AuNPs not only immobilized GOD molecules, but also could catalyze O2 reduction.•The jO2/jCu-BTC was measured as response signal for ratiometric electrochemical biosensor.•The biosensor exhibited good performance with high accuracy, selectivity and reproducibility. Cu-trimesic acid metal-organic frameworks (Cu-BTC MOFs) were firstly grown on three-dimensional macroporous carbon integrated electrode (3D-KSCs), then Au nanoparticles (AuNPs) were electrodeposited on Cu-BTC MOFs/3D-KSCs electrode and finally glucose oxidase (GOD) was immobilized to construct a ratiometric electrochemical glucose biosensor. Scanning electron microscopy was employed to monitor the modified process of GOD/AuNPs/Cu-BTC MOFs/3D-KSCs electrode. Electrochemical techniques were applied to explore the electrochemical behaviors of GOD/AuNPs/Cu-BTC MOFs/3D-KSCs electrode, which showed the reduction peaks of O2 and Cu-BTC MOFs. The reduction peak current density of O2 decreased and the reduction peak current density of Cu-BTC MOFs increased with the increase of glucose concentration less than 4mM. However, the reduction peak current of O2 was still declined while the reduction peak current of Cu-BTC MOFs maintained constant with the addition of glucose beyond 4mM. The jO2/jCu-BTC was considered as the response signal which exhibited a good linear range with the glucose concentration from 44.9μM to 4.0mM and from 4.0 to 19mM, and the detection limit was 14.77μM. The as-prepared biosensor also showed high accuracy, high selectivity and good reproducibility. The work gave a first example to use electroactive MOFs as reference signal for ratiometric electrochemical sensor.