自组装溶液酸度对L-半胱氨酸自组膜的结构与性能的影响

L-半胱氨酸（L-Cys）自组装单分子膜（SAM）已在化学传感器及生物传感器研究领域得到了广泛应用.但是,L-Cys SAM容易通过静电吸附或分子间氢键形成二聚体,而降低表面功能基团的活性,进而对生物传感器的性能产生不利影响.首先在不同pH条件下,将L-Cys自组装在金电极表面,用循环伏安法、交流阻抗法和偏振模式傅里叶变换红外反射吸收光谱法对L-Cys SAM进行表征.结果表明,在pH 3.0的醋酸盐缓冲溶液中于金表面上制备L-Cys SAM可以较为有效的抑制二聚体的形成,为蛋白质的固定化提供了理想的界面,为进一步制备免疫传感器、酶传感器等生物传感器提供了技术支持.

Effect of self-assembly solution acidity on structure and performance of self-assembled monolayers of L-Cysteine on Au electrode

The self-assembled monolayers（SAMs） of L-Cysteine（L-Cys） have been widely used in development of the chemical sensors and the Bioseneors.However,the formation of L-Cys dimer by the electro-static absorption or intermolecular hydrogen bonds may reduce the activity of surface functional group of L-Cys SAMs,thus limit its application of L-Cys SAMs in biological sensing technology.In this study,the L-Cys have been assembled on gold electrode surface under different pH conditions,and were characterized by cyclic voltammetry,the electrochemical impedance spectroscopy technique and polarization mode FTIR reflection absorption spectroscopy.The results showed that the L-Cys SAMs preparated on the gold surface in acetate buffer solution（pH 3.0） can effectively inhibit formation of dimer,and provides an ideal interface for immobilization of protein.The results provide technical support for the preparation immunosensors,enzyme sensors.