Preparation of cinchonine molecularly imprinted photonic crystal film and its specific recognition and optical responsive properties.

The cinchonine molecularly imprinted photonic polymer (MIPP) film was prepared by using methacrylic acid as functional monomer, ethylene glycol dimethacrylate as cross linker, benzoyl peroxide and N,N-dimethylaniline as initiation system by a combination of colloidal crystal template method and molecular imprinting technique. The structure and morphology of the polymer film were characterized by infrared spectra and scanning electronic microscope. The results exhibit that a highly ordered threedimensionally interconnected macroporous array with typical face-centered cubic (fcc) structure was formed in the MIPP film. The binding experiments showed that the special, hierarchical porous structure enabled this polymer to possess rapid adsorption kinetics, improved binding capacity, and specificity to analytes. The Bragg diffractive measurements showed that the MIPP film has good specific responsiveness for the template molecules. The Bragg diffraction peaks shifted from 527 to 503 nm with the concentration of the cinchonine varying from 0 to 10^-3 mol/L, whereas there were no obvious peaks shifts for its structural analogues. This may be ascribed that the changes in the lattice constants and the average refractive indices of MIPP film caused by the special adsorption of template molecules toward recognition sites. [ABSTRACT FROM AUTHOR]