Li Wanzhen, Ding Longhua, Wang Qiaohong, Su Bin
Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Hangzhou 310058, China.
Analyst. 2014 Aug 21;139(16):3926-31. doi: 10.1039/c4an00605d.
A thin film consisting of highly ordered and vertically oriented silica mesochannels (SMCs) was prepared on the indium tin oxide (ITO) coated glass electrode surface by chronopotentiometry. The mesochannel has a uniform pore size of 2-3 nm in diameter and a positively charged surface due to grafted ammonium groups. The electrostatic and steric effects resulted from control of the surface charge and the ionic buffer concentration make the SMCs permselective, favoring the mass transport of oppositely charged species and repelling that of similarly charged ones. By using differential pulse voltammetry (DPV), the SMCs with this charge selectivity can be employed for permselective detection of ascorbic acid (AA) and dopamine (DA) that are oppositely charged compounds. The obtained linear detection range was 49-2651 μM for AA and 20-226 μM for DA, respectively. AA and DA in real samples were also determined by the SMC film modified electrode.
通过计时电位法在氧化铟锡（ITO）包覆的玻璃电极表面制备了一种由高度有序且垂直取向的二氧化硅介孔通道（SMC）组成的薄膜。该介孔通道的孔径均匀，直径为2 - 3纳米，由于接枝了铵基团，其表面带正电荷。对表面电荷和离子缓冲液浓度的控制所产生的静电和空间效应使SMC具有选择透过性，有利于带相反电荷物质的质量传输，而排斥带相同电荷物质的传输。通过使用差分脉冲伏安法（DPV），这种具有电荷选择性的SMC可用于对带相反电荷的化合物抗坏血酸（AA）和多巴胺（DA）进行选择透过性检测。所获得的线性检测范围分别为AA的49 - 2651 μM和DA的20 - 226 μM。实际样品中的AA和DA也通过SMC薄膜修饰电极进行了测定。
