Theoretical and experimental study of valine molecular imprinted polymer using sol-gel process on silica microparticles surface

Abstract

Molecular imprinted polymer using sol-gel process on silica microparticles surface has been prepared using valine as a template, 3-aminopropyltriethoxysilane (APTES) as the functional monomer, and tetraethoxysilane (TEOS) as the cross-linker. The theoretical results of molar ratio 1:2 (Valine:APTES) showed highest interaction energy with -3.8479 kcal/mol. The molecular imprinted polymer (MIP) and non-imprinted polymer (NIP) were prepared followed by characterization and evaluation of the absorption binding performance of imprinted valine. Observation of MIP morphology on Scanning Electron Microscopy (SEM) showed that the surface of silica were coated with imprinted polymer. In Fourier-Transform Infra-Red Spectroscopy (FT-IR), the strong intensity peaks were observed at 2921.71cm−1 and 1500cm−1 represent the functional group of alkane due to presence of the C-H stretching and C - N vibration from APTES of functional monomer, respectively. Observations in MIP and NIP samples confirmed the existence of a monomer and cross-linker on the silica surface. However, the experimental binding capacity result contradict the theoretical computation, where the experimental binding capacity showed that the maximum absorption binding capacity was at molar ratio 1:1 instead of 1:2. In conclusion, this novel molecular imprinted technology might efficiently be used in the identification and selection of amino acid fragments such as valine on its biological action.