反射干涉光谱法测定分子印迹敏感膜表面吸附的分子浓度

Determination of Concentration of Molecule Adsorbed on Molecular Imprinted Membrane by Reflectometric Interference Spectroscopy

采用旋转涂膜法在镀有五氧化二钽增强层的载玻片上制备氯霉素分子印迹敏感膜,将印迹敏感膜玻片置入不同浓度氯霉素溶液中进行吸附试验,采用反射干涉光谱检测印迹膜吸附前后的光学厚度变化值(Δnd),溶液浓度与Δnd之间呈线性关系,线性回归方程为Δnd=-0.37+0.20c,检出限(3s/k)为0.15 mmol.L-1。该法用于加标蜂蜜样品中氯霉素的测定,所得结果与高效液相色谱法测定结果相符,回收率为96.5%,相对标准偏差(n=5)为0.8%。

Sensitive molecular imprinted membrane of chloramphenicol（CAP） was prepared by spin-coating on glass slides with strengthened layer of Ta2O5.The sensitive molecular imprinted membrane prepared were immersed in CAP solutions of different concentrations,and test for adsorptivity was performed.The variation of optical thickness（Δnd） of the molecular imprinted membranes before and after absorbing CAP were determined by reflectometric interference spectroscopy（RIfS）.Linear relationship between values of Δnd and concentration of CAP was obtained as shown by the linear regression equation,Δnd=-0.37＋0.20 c.Value of detection limit（3s/k） found was 0.15 mmol·L-1.The proposed method was used in the analysis of honey sample added with standard CAP,and the results obtained were in conformity with those found by HPLC.The values of recovery and RSD（n=5） found were 96.5% and 0.8%,respectively.