通过电聚合的方法在玻碳电极表面形成聚瓜氨酸膜（PCit/GCE），制备了聚瓜氨酸玻碳电极，用于测量烟酰胺（NA），建立了测定烟酰胺的新方法。结果表明，利用PCit/GCE测定烟酰胺有较高的灵敏度，还原峰电流明显增强，烟酰胺检出浓度4.0×10^-7 mol/L。烟酰胺浓度还原峰电流在4.00×10^-6~1.00×10^-4 mol/L范围内有良好的线性关系，线性方程式为i_pc（A）=5.32×10^-7+0.36c（mol/L），相关系数R为0.993 9。PCit/GCE修饰电极测定护肤品和奶粉中的NA，回收率分别为96.1%、97%。

Polycitrulline (PCIT) modified glass-carbon electrode (PCIT/GCE) is obtained through forming polycitrulline film on the surface of a glass-carbon electrode (GCE) by electro-polymerization method, and used to detect nicotinamide, which represents a new method for the determination of niacinamide.It is found that PCIT/GCE has a higher sensitivity in detecting nicotinamide with a significantly enhanced reduction peak current.The peak current appears at a nicotinamide concentration of 4.0×10^-7 mol·L^-1.It is verified there is a good liner relationship between current intensity and nicotinamide concentration in the range of 4.00×10^-6-1.00×10^-4 mol·L^-1.The linear equation is i_pc(A)=5.32×10^-7+0.36c(mol·L^-1), and the correlation coefficient is 0.993 9.The recoveries are 96.1% and 97%, respectively when PCIT/GCE modified electrode is used to determine nicotinamide in skin care products and milk powder.

尹明静(1977-),女,硕士,讲师,研究方向为电化学和超分子化学,hzxyymj@163.com。