Bisphenol A (BPA)-imprinted polymer for the binding and molecular recognition of bisphenol compounds

• Main Author: Abucayon, Erwin G.
• Format: text
• Language: English
• Published: Animo Repository 2012
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/4298
• Institution: De La Salle University

Bisphenol compounds such as BPA, BADGE and BFDGE are known carcinogenic and mutagenic contaminants that can leach to food from the can packaging. Tolerable limits set by regulatory institutions suggest a stringent analytical technique to analyze and remove these toxic substances. Molecular imprinting is a technique of introducing active recognition sites in the polymer matrix, hence the prepared polymeric materials could selectively bind target compound. This study aims to synthesize and characterize BPA-imprinted polymer (MIP) as potential sorbent for bisphenol compounds. In the rational design of MIP, MMFF94 theoretical technique was used to assess the favorable binding energies of interacting template-monomer systems, template-monomer ratios and rebinding solvents that could possibly impart good imprinting characteristics. The ideal MAA-BPA (4:1) molar ratio of the synthesized polymers and the rebinding solvent (50% ACN/50% toluene) was established via computational technique using MMFF94. The new BPA-imprinted polymer was synthesized by precipitation polymerization using mecthacrylic acid (MAA), bisphenol A (BPA), trimethylolpropane trimethacrylate (TRIM), and 2,2azobis(isobutyronitrile) (AIBN) as functional monomer, template, cross-linker, and initiator, respectively. Results of infrared spectroscopy, fluorescence microscopy and elemental analysis revealed that molecularly imprinted polymer (MIP) was successfully synthesized. Scanning electron micrograph showed that the MIP’s are relatively uniform microparticles with high degree of porosity. This suggests that these imprinted polymers are suitable as sorbent for column separation. xvi Scatchard plot characterized MIP as having two binding recognition types. The stronger affinity binding type exhibits dissociation constant (Kd) 20 times smaller that that of the weaker type with binding capacity of 68.597 mg BPA/g MIP. Subsequent Freundlich isotherm further demonstrated the heterogeneity of the binding sites of the MIP with heterogeneity index, a (0.4758)