使用全氟磺酸-六氰合铁酸钴薄膜修饰电极对多巴胺进行电氧化及测定

Castro Suely S L, Mortimer Roger J, De Oliveira Marcelo F, Stradiotto Nelson R

UERN - FANAT - Departmento de Química, 59600-010 - Mossoró, RN, Brazil.

Loughborough University - Department of Chemistry, Loughborough, LE11 3TU, UK.

Sensors (Basel). 2008 Mar 19;8(3):1950-1959. doi: 10.3390/s8031950.

The electrocatalysis of dopamine has been studied using a cobalt hexacyanoferrate film (CoHCFe)-modified glassy carbon electrode. Using a rotating disk CoHCFe-modified electrode, the reaction rate constant for dopamine was found to be 3.5 × 105 cm³ mol s at a concentration of 5.0 × 10 mol L. When a Nafion film is applied to the CoHCFe-modified electrode surface a high selectivity for the determination of dopamine over ascorbic acid was obtained. The analytical curve for dopamine presented linear dependence over the concentration range from 1.2 × 10 to 5.0 × 10 mol L with a slope of 23.5 mA mol L and a linear correlation coefficient of 0.999. The detection limit of this method was 8.9 × 10-6 mol L and the relative standard deviation for five measurements of 2.5 × 10-4 mol L dopamine was 0.58%.

已使用六氰合铁酸钴薄膜（CoHCFe）修饰的玻碳电极研究了多巴胺的电催化作用。使用旋转圆盘CoHCFe修饰电极，发现在浓度为5.0×10⁻⁵ mol/L时，多巴胺的反应速率常数为3.5×10⁵ cm³ mol⁻¹ s⁻¹。当在CoHCFe修饰电极表面涂覆Nafion膜时，对多巴胺的测定相对于抗坏血酸具有高选择性。多巴胺的分析曲线在1.2×10⁻⁵至5.0×10⁻⁴ mol/L的浓度范围内呈线性关系，斜率为23.5 mA mol⁻¹ L，线性相关系数为0.999。该方法的检测限为8.9×10⁻⁶ mol/L，对2.5×10⁻⁴ mol/L多巴胺进行五次测量的相对标准偏差为0.58%。