Screening of functional monomers and preparation of molecularly imprinted polymers (MIPs) in molecularly imprinted polymers of steranes

To prepare molecularly imprinted polymers (MIPs) with specific selectivity for steranes, the prepolyme-rization system was screened by UV spectroscopy to determine the type, proportion and mode of action of functional monomers. In this study, the interaction intensities between three template molecules (cholesterol, β-sitosterol, deoxycholic acid) and four functional monomers (acrylic acid (AA), methacrylic acid (MAA), methyl methacrylate (MMA), and acrylamide (AM)) are compared respectively. The results show that the functional monomer AA can interact strongly with the three template molecules and form a stable prepolymerization system, so AA is selected as the functional monomer of MIPs. In addition, the UV spectral absorbance change and differential UV spectral analysis of different proportions of AA show that the optimal concentration ratios of the three template molecules to functional monomer AA are all 1:4, and the stable complex configurations formed are cholesterol-1AA, β-sitosterol-1AA and deoxycholic acid-3AA, respectively. The MIPs are successfully synthesized by precipitation polymerization using EDGMA as dispersant and AIBN as initiator, and the results of FTIR show that MIPs are well prepared. Therefore, this method can be used for the screening and preparation of MIPs functional monomers with specific selectivity for steranes, and provide technical support for the study of oil-source correlation between deep and ultra-deep source rocks.