电化学传感法测定水中亚硝酸盐

摘要

Poly ( bromophenol blue) film modified glassy carbon electrode was fabricated through a simple and controllable in situ electro-polymerizing method, and experiment results show that the poly ( bromophenol blue) film has good catalytic ability to the electrochemical oxidation of nitrite. The optimal thick of poly ( bromophenol blue) film was electro-polymerized for 20 cycles and the optimal detection electrolyte was 0�01 mol/L pH=4�0 phosphat buffer solution. Moreover, the electrochemical oxidation of nitrite on the sensor was a two-electron and two-proton participation process. The sensor has wide linear range, low detection limit, good stability and anti-interference ability et al. At last, this sensor was successfully applied in detecting nitrite from water of the East lake.%借助于简单可控的在线电聚合方法，溴酚蓝被修饰到玻碳电极表面，制备了聚溴酚蓝修饰玻碳电极。实验表明，聚溴酚蓝薄膜对于亚硝酸盐的电化学氧化具有很好的催化作用。经实验优化，聚溴酚蓝膜的最佳厚度为聚合20圈，最佳的检测底液为pH＝4�0的0�01 mol/L磷酸盐缓冲溶液。亚硝酸盐在传感器上的电化学氧化是一个双电子双质子参与的过程。在最佳检测条件下，亚硝酸盐的氧化峰电流与其浓度在0�02～109�1μmol/L范围内有良好的线性关系，检测限低至5 nmol/L（S/N＝3），所制备的亚硝酸盐传感器线性范围宽、检出限低、稳定性和重现性好、抗干扰能力强，将传感器应用于东湖水样中亚硝酸盐含量的测定，结果令人满意。