基于表面活性剂单分子层修饰碳糊电极的一氧化氮电化学传感器及其应用

Electrochemical Sensor of Nitric Oxide Based on Self-Assembled Monolayer of Surfactant on Carbon Paste Electrode and Its Application in Biological System

报道了一种表面活性剂单分子层修饰碳糊电极,并用于NO的高灵敏电化学检测。研究表明,表面活性剂通过烷基链在电极表面形成的疏水性单分子层微环境对NO的电化学响应具有较好的促进作用。其中,阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)对NO的电化学氧化表现出最强的催化活性和增敏作用。在Nafion膜覆盖的CTAB修饰碳糊电极上,NO的安培响应与其浓度在3.6×10-8～1.8×10-5mol/L范围内呈良好的线性关系,检出限为1.8×10-8mol/L。该电极作为低成本、高灵敏的NO电化学传感器,被成功应用于大鼠肺组织细胞中NO释放的实时监测。

In this work,a novel electrochemical sensor of nitric oxide （NO） based on a surfactant self-assembled monolayer modified carbon paste electrode （CPE） was reported. The monolayer of surfactant on CPE was believed to create a hydrophobic microenvironment favorable to the accumulation of NO on CPE. A cationic surfactant,cetyltrimethylammonium bromide （CTAB）,exhibited the strongest catalytic activity and accumulation capacity for the electrochemical oxidation of NO at CPE. The amperometric response of NO at a Nafion film coated CTAB modified CPE was in a good linear relationship with its concentration in the range of 3.6×10-8~1.8×10-5 mol/L,along with a low detection limit of 1.8×10-8 mol/L （S/N=3）. This NO electrochemical sensor was successfully applied to the real-time monitoring of NO release from lung tissue cells of rat by the stimulation of L-argentine （L-Arg）.