Glucose Biosensor Based on a Glassy Carbon Electrode Modified with Polythionine and Multiwalled Carbon Nanotubes

Abstract

A novel glucose biosensor was fabricated. The first layer of the biosensor was polythionine, which was formed by the electrochemical polymerisation of the thionine monomer on a glassy carbon electrode. The remaining layers were coated with chitosan-MWCNTs, GOx, and the chitosan-PTFE film in sequence. The MWCNTs embedded in FAD were like “conductive wires” connecting FAD with electrode, reduced the distance between them and were propitious to fast direct electron transfer. Combining with good electrical conductivity of PTH and MWCNTs, the current response was enlarged. The sensor was a parallel multi-component reaction system (PMRS) and excellent electrocatalytic performance for glucose could be obtained without a mediator. The glucose sensor had a working voltage of −0.42 V, an optimum working temperature of 25°C, an optimum working pH of 7.0, and the best percentage of polytetrafluoroethylene emulsion (PTFE) in the outer composite film was 2%. Under the optimised conditions, the biosensor displayed a high sensitivity of 2.80 µA mM−1 cm−2 and a low detection limit of 5 µM (S/N = 3), with a response time of less than 15 s and a linear range of 0.04 mM to 2.5 mM. Furthermore, the fabricated biosensor had a good selectivity, reproducibility, and long-term stability, indicating that the novel CTS+PTFE/GOx/MWCNTs/PTH composite is a promising material for immobilization of biomolecules and fabrication of third generation biosensors.

Development of a new biocathode for a single enzyme biofuel cell fuelled by glucose

“…Therefore, the formation of an additional layer of PPCA causes a decrease in the intensity of the redox peaks. For the GR/PB-PPCA/PPCA–GOx, an even greater decrease in redox peaks intensity was observed due to nonconducting nature of enzyme 33 , 34 immobilized on the surface. In addition, as shown in Fig.…”

Electrochemical design of a new nanosensor based on cobalt nanoparticles, chitosan and MWCNT for the determination of daclatasvir: a hepatitis C antiviral drug

“…This response time is lower than that observed by Arora et al 31 (60 s), Ali and Mohamed 32 (5 s). Du et al 33 with response time of 7 s and Tang et al 34 biosensor with a response time of less than 15 s.…”

Multiparameter Microwave Characterization and Probing of Ultralow Glucose Concentration Using a Microfabricated Biochip

“…Table 1 presents the values of the impedances and frequencies of the resonance peaks with the respective RSDs of the proposed biochip for serum samples of varying glucose concentrations. The proposed biochip exhibits a glucose detection limit at least 19 times lower than several previously reported EIS-based glucose biosensors [ 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 ].…”