激光反射仪在溶液吸附动力学研究中的应用

Application of Adsorption-desorption Process on Silica by Laser Reflectometry

激光反射仪为定量测量溶液表面吸附力的有效工具,为保证其测定灵敏度的方法,通过实验,将激光光学反射仪应用于溶液吸附上,反射仪的反射界面上安置一个S iO2硅片,硅片薄膜可提高反射束中产生周相移动的灵敏度,设备通过仪器校正和光学模型,可以计算不同吸附层厚度灵敏度的线性关系.并应用该技术测定了一种非离子表面活性剂C12EO5和2种蛋白质BSA,LSZ溶液的吸附动力学,单位面积上吸附量能够检测到低至0.01 mg/m2.

This paper discusses laser reflectometry as a tool studies adsorption from dilute solutions,and elaborates on the kind of reflectometry where the reflecting substrate carries a thin dielectric film on which the adsorption takes place.The role of this film is to enhance the sensitivity of the method by producing a suitable phase shift in the reflected beam.The experimental device,calibration procedure and some conditions for successful determination of the surface excess are described.By means of an optical model sensitivity and linearity of the technique for various thickness of the adsorbed layer are calculated.Reflectometry was used to investigate the adsorption behaviour of nonionic surfactant C12EO5 solution and two protein solutions,namely bovine serum albumin and lysozyme.And provided such optimum conditions are chosen,adsorbed amounts as low as 0.01 mg/m2 can be detected.