铋-卟啉复合电极电化学检测研究

Study on Electrochemical Detection of Bismuth-porphyrin Composite Electrode

将卟啉与铋膜复合到玻碳电极表面,用制得的铋-卟啉复合玻碳电极对亚硝酸盐进行检测,与未修饰和只修饰卟啉的玻碳电极比对,通过方波伏安法对同等浓度的亚硝酸盐进行检测,峰电流明显升高,说明该复合电极对亚硝酸盐有较大的电催化作用。通过对镀铋的方法、缓冲溶液和pH值等测定条件进行优化,选取最佳的测定条件。结果表明,在8~20 mmol/L浓度范围内,峰电流和亚硝酸盐浓度呈现较好的线性关系,线性方程I=0.2011c+8.4860;相关系数R^(2)=0.9988。将复合电极放置两周后平行测定亚硝酸盐14次,峰电流值稳定。用该复合玻碳电极测定火腿肠中的亚硝酸盐,其回收率为98.64%~100.8%。

The porphyrin and bismuth membrane were associated with the surface of the carbon-glass electrode.To demonstrate that the composite electrode had a large electrocatalytic effect,and their peak currents increased compared with which was not decorated and porous porphyrin carbon-glass in determinating of the nitrite content by square wave voltammetry wave.For nitrite tested the same concentration of nitrite by square wave voltammetry was determined by optimizing the methods of coating bismuth film method,and pH value of buffering.The results showed that nitrite showed a good linear relationship from 8 to 20 mmol/L and linear equation I=0.011c+8.4860,the correlation coefficient R^(2)=0.9988.After two weeks,the composite electrode was placed in parallel to determine the nitrite 14 times,and the peak current was very stable.The recovery rate was from 98.64%to 100.8%.