基于含有活性铜的碳点电化学传感器选择性检测尿酸

摘要

The active copper-containing carbon nanodots were prepared by hydrothermal method, and then characterized by fluorescence spectroscopy and UV-visible absorption spectroscopy.Subsequently, a highly sensitive and selective electrochemical biosensor was fabricated on the basis of this synthesized carbon nanodots with electro-deposition technique.The electrode behavior was investigated by cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse voltammetry.Furthermore, the catalysis mechanism was studied.The experimental results indicated that the biosensor exhibited a strong electrocatalytic activity toward the oxidation of uric acid (UA).What′s more, the interference from ascorbic acid and dopamine was eliminated effectively.Under the optimum conditions, there were linear relationships between the anodic peak current and the concentration of UA (1.00-300.0 μmol/L), and the limit detection was 0.30 μmol/L (S/N=3).The prepared biosensor had advantages such as easy fabrication, strong anti-interference ability, high sensitivity, and wide detection range, and could be used for real sample detection.%采用水热法制备了含有活性铜的碳点,利用荧光光谱和紫外可见吸收光谱对其光学性质进行了表征.通过电沉积法将其修饰于玻碳电极表面, 构建了电化学生物传感器,采用循环伏安法、交流阻抗法和差分脉冲伏安法对电极的电化学行为进行了考察, 并对其电化学反应机理进行了探讨.结果表明,此传感器对尿酸具有良好的电催化效果,可有效消除抗坏血酸和多巴胺等物质的干扰.在最佳条件下,氧化峰电流与尿酸的浓度在1.00~300 μmol/L范围内呈良好的线性关系, 检出限为0.30 μmol/L(S/N=3).此传感器具有制作简单、选择性好、灵敏度高和线性范围宽等优点,有望应用于实际样品的检测.