A new type of sol-gel/organic hybrid composite film based on chitosan(CS) with methytrimethoxysilane(MTOS) was developed for the fabrication of an amperometric glucose biosensor. The hybrid composite film was used to ...A new type of sol-gel/organic hybrid composite film based on chitosan(CS) with methytrimethoxysilane(MTOS) was developed for the fabrication of an amperometric glucose biosensor. The hybrid composite film was used to immobilize glucose oxidase(GOD) on the surface of Prussian Blue(PB)-modified glass carbon electrode. Effects of some experimental conditions such as pH, temperature and applied potential etc. on the current response of the biosensor were investigated. The biosensor has a fast response less than 10 s and linear calibration range from 5.0×10 -6 to 2.4×10 -3 mol/L with detection limit of 1.0×10 -6 mol/L. The apparent Michaelis-Menten constant K m is found to be 3.2×10 -3 mol/L. The activation energy for enzymatic reaction is calculated to be 21.9 kJ/mol. The biosensor has a high sensitivity(420 μA·mol -1·L), long-term stability and good selectivity. This method has been used to determine the content of glucose in the real blood samples.展开更多
The interaction between Alizarin red(AR) and Chitosan(CS) was investigated in (0.1 mol/L) HAc-NaAc buffer solution(pH=4.5) on the glassy carbon electrode(GC) by cyclic and square wave voltammetry. The result...The interaction between Alizarin red(AR) and Chitosan(CS) was investigated in (0.1 mol/L) HAc-NaAc buffer solution(pH=4.5) on the glassy carbon electrode(GC) by cyclic and square wave voltammetry. The results show that both AR and AR-CS complex have a well-defined quasi-reversible redox wave(Vpc=-0.46 V, Vpa=-0.41 V) with adsorption characteristics. Electron transfer coefficient(α) and reaction rate constant(Ks) of AR and AR-CS were measured by cyclic voltammetry. The maximum binding numbers m between AR and CS was found to be 2 500. The experiment results confirmed that lower concentration of CS can enhance the detection sensitivity, while higher concentration of CS can lower the detection sensitivity. In the presence of 2.0×10-5 mol/L AR, the peak current of system are proportional to CS concentration in the range of 1.25×10-8~2.5×10-7 mol/L, and inversely proportional to CS concentration in the range of 2.5×10-7~1.25×10-5 mol/L, respectively. The binding interaction mechanism was also discussed.展开更多
文摘A new type of sol-gel/organic hybrid composite film based on chitosan(CS) with methytrimethoxysilane(MTOS) was developed for the fabrication of an amperometric glucose biosensor. The hybrid composite film was used to immobilize glucose oxidase(GOD) on the surface of Prussian Blue(PB)-modified glass carbon electrode. Effects of some experimental conditions such as pH, temperature and applied potential etc. on the current response of the biosensor were investigated. The biosensor has a fast response less than 10 s and linear calibration range from 5.0×10 -6 to 2.4×10 -3 mol/L with detection limit of 1.0×10 -6 mol/L. The apparent Michaelis-Menten constant K m is found to be 3.2×10 -3 mol/L. The activation energy for enzymatic reaction is calculated to be 21.9 kJ/mol. The biosensor has a high sensitivity(420 μA·mol -1·L), long-term stability and good selectivity. This method has been used to determine the content of glucose in the real blood samples.
文摘The interaction between Alizarin red(AR) and Chitosan(CS) was investigated in (0.1 mol/L) HAc-NaAc buffer solution(pH=4.5) on the glassy carbon electrode(GC) by cyclic and square wave voltammetry. The results show that both AR and AR-CS complex have a well-defined quasi-reversible redox wave(Vpc=-0.46 V, Vpa=-0.41 V) with adsorption characteristics. Electron transfer coefficient(α) and reaction rate constant(Ks) of AR and AR-CS were measured by cyclic voltammetry. The maximum binding numbers m between AR and CS was found to be 2 500. The experiment results confirmed that lower concentration of CS can enhance the detection sensitivity, while higher concentration of CS can lower the detection sensitivity. In the presence of 2.0×10-5 mol/L AR, the peak current of system are proportional to CS concentration in the range of 1.25×10-8~2.5×10-7 mol/L, and inversely proportional to CS concentration in the range of 2.5×10-7~1.25×10-5 mol/L, respectively. The binding interaction mechanism was also discussed.