Heparin Epitope Imprinted Via Sol-Gel Process on Silica Surface: Effect of Template: Monomer Ratio Studies

Heparin, a sulfated glycosaminogylcan (GAG) is one of macromolecule natural compounds and widely used as an anticoagulant drug, anti-thrombotic agent and hemodialysis (patients undergoing kidney dialysis). Since it is derived from animal source, heparin can contain several natural contaminants. Thus, molecular imprinting technology is introduced for purification and separation of heparin. An epitope extraction was implemented consist of low molecular weight heparin (LMWH) as template to capture large molecule of heparin which prepared by sol-gel process on the surface of macromolecule silica using 3-aminopropyltriethoxysilane (APTES) and tetraethoxysilane (TEOS) and functional monomer and cross-linker respectively. Here, the effect of template: monomer ratio was evaluated and result shown that the (1:2) ratio of template to functional monomer successfully adsorb and enrich the heparin protein. The imprinted polymer was characterized with Fourier Transform Infrared (FTIR) spectroscopy, Thermogravimetric Analysis (TGA), Brunauer-Emmet-Teller (BET) and Field Emission Scanning Electron Microscopy (FESEM). The adsorption behaviours of epitope imprinting indicated that Langmuir-Freundlich (single-site) was considered as the model with better fit and kinetic batch studies showed pseudo-first-order kinetic model via physicochemical process. The results obtained good imprinting comparable of epitope imprinting effect.