镍铝类水滑石修饰玻碳电极对槲皮素痕量检测研究

Determination of Quercetin by Glassy Carbon Electrode Modified With Ni^(2+)-Al^(3+)-LDHS

用滴涂法制备了镍铝类水滑石修饰玻碳电极(Ni^(2+)-Al^(3+)-LDHs/GCE),通过 FT-IR、SEM 对修饰电极进行了表征。采用循环伏安法(CV)、方波伏安法(SWV)等电化学方法研究了槲皮素在该修饰电极上的电化学行为。结果表明:该修饰电极对槲皮素具有良好的电催化活性。在优化的条件下,用方波伏安法测得槲皮素的峰电流 I_(pa)与其浓度 c 在 3.0×10^(-6)-5.0×10^(-8)mol·L^(-1)范围内有良好的线性关系,线性方程为 I (μA)=0.664 1 c-0.011 6,γ^(2)=0.998 5。检出限(S/N=3)为 1.75×10^(-8)mol·L^(-1),该方法用于槐花和洋葱提取液中槲皮素浓度的测定,测得槐花中槲皮素质量分数为 0.94%,洋葱中槲皮素质量分数为 0.003 4%。该修饰电极制备方法简单、灵敏度高、重现性和稳定性好,为槲皮素痕量检测提供了新的方法。

Nickel-aluminium hydrotalcite modified glassy carbon electrode (Ni^(2+)-Al^(3+)-LDHS/GCE) was prepared by drop coating method, and it was characterized by FT-IR and SEM. The electrochemical behavior of quercetin on the modified electrode was studied by cyclic voltammetry(CV) and square wave voltammetry(SWV). The results showed that the modified electrode exhibited a high electrocatalytic activity for quercetin. Under the optimum conditions,the peak current had linear relationships with concentration of quercetin in the ranges of 3.0×10^(-6)mol·L^(-1)to 5.0×10^(-8)mol·L^(-1), the linear equation was I(μA)= 0.6641 c+ 0.0116(γ^(2)=0.998 5). The detection limit(S/N=3)was 1.75×10^(-8)mol·L^(-1).The proposed method was successfully applied in the detection of Locust flowers and Onions,the quercetin mass fractions in them were 0.94% and 0.0034% respectively.Furthermore,the modified electrode has the advantages of simple preparation, high sensitivity, good reproducibility and stability, providing a new method for the determination of quercetin trace.