Study of self-assembly system of norfloxacin molecularly imprinted polymers based on simulated design

Abstract

To rationally design molecularly imprinted polymers (MIPs) of norfloxacin (NOR), functional monomers, cross-linking agents, and solvents were screened by using the LC-WPBE/6-31G(d,p) method. The nature of the interaction between NOR imprinted molecules and trifluoromethylacrylic acid (TFMAA) functional monomers is discussed. The functional monomers were screened based on the interaction ratio, the number of bonds, and the binding energy of the stable complexes between NOR and 4-vinylpyridine, methacrylic acid, TFMAA, and 2-vinyl-4,6-diamino-1,3,5-triazine. The selection of cross-linking agent was carried out based on the binding energy when the molar ratio of cross-linking agent TFMAA was 1:1. The solvent was optimized by calculating the solvation energy of the NOR–TFMAA stable complex (1:1) using different solvents. The nature of imprinting was obtained by the topological analysis of electron density of stable complexes of NOR and TFMAA based on the atom in molecule theory. On the basis of computational results, TFMAA, trimethylolpropane trimethylacrylate, and toluene were selected as the functional monomer, cross-linking agent, and solvent, respectively. When the molar ratio of NOR:TFMAA was 1:7, the complex that was formed had the lowest binding energy and highest number of hydrogen bonds. In addition, the O and H atoms on the quinoline ring and the N and H atoms on the piperazine ring of NOR interacted with TFMAA and formed ordered complexes matching each other in chemical groups and steric configuration via hydrogen bonding. Therefore, this study can provide a theoretical basis and reference for the design and preparation of NOR–MIPs.