摘要
利用循环伏安法(CV)制备了薄而稳定的银和甘氨酸聚合物膜修饰电极,研究了VC在此电极上的电化学行为,建立了循环伏安法测定食品中VC的新方法。银和甘氨酸复合膜修饰电极对VC的电化学氧化具有明显的催化作用。在pH 5.0磷酸盐缓冲溶液(PBS)中,氧化峰电流(ipa)与其浓度(c)在1.6×10-6～3.0×10-3mol/L内呈良好的线性关系,线性方程为:ipa=-8.48×10-7+0.023 c(mol/L),相关系数为0.999 9;检出限为1.2×10-7mol/L。银掺杂甘氨酸膜电极可以消除食品中一些共存物质如VA、柠檬酸和苹果酸等的干扰,修饰电极具有良好的灵敏度、选择性和稳定性,试验中用于辣椒中VC的测定,结果满意。
A silver doped polyglycine modified electrode was prepared to yield thin and stable polymeric films by cyclic vohammetry （CV）. The electrochemical behavior of vitamin C at the modified electrode was studied. A novel method for determination of vitamin C using cyclic vohammetry was established. The modified electrode showed an ex- cellent electrocatalytical effect on the oxidation of vitamin C. In pH5.0 phosphate buffer solution （PBS）, the oxidation peak current versus the concentration of vitamin C showed a linear relations over the range of 1.6 x 10 -6 -3.0 x 10 -3 mol/L with a correlation coefficient as follows ：ipa = - 8.48 x 10-7 ＋ 0. 023c （mol/L） , R = 0. 999 9 ; the detection limit was 1.2 x 10-7 mol/L. The recovery was 95.0% ~ 101.0%. Major interferences such as vitamin A, citric acid and malic acid were tested at this silver and polyglycine compound modified electrode and found that selective detec- tion of can be achieved. This new method has been successfully applied for the determination of vitamin C in cayenne with satisfactory results in this test.
出处
《食品与发酵工业》
CAS
CSCD
北大核心
2012年第4期184-187,共4页
Food and Fermentation Industries
基金
山东省高等学校科技计划项目(J10LB64)
菏泽学院科研基金科技计划项目(XYJJKJ-4)
关键词
VC
甘氨酸
银掺杂
食品
vitamin C, glycine, silver doped, food
