Preparation, functionalization and characterization of rice husk silica for lipase immobilization via adsorption.

Silica has been extracted from rice husks via a simple hydrothermal process and functionalized with triethoxy(octyl)silane -OCTES (Octyl-SiO) and (3-aminopropyl)triethoxysilane - 3-APTES (Amino-SiO), with the aim of using it as support to immobilize lipase from Thermomyces lanuginosus (TLL) via adsorption. The supports have been characterized by particle size distribution and elemental analyses, XRD, TGA, SEM, AFM and N physisorption so as to confirm their functionalization. Effect of pH, temperature, initial protein loading and contact time on the adsorption process has been systematically evaluated.

Preparation of ion-exchange supports via activation of epoxy-SiO with glycine to immobilize microbial lipase - Use of biocatalysts in hydrolysis and esterification reactions.

Ion-exchange supports have been prepared via sequential functionalization of silica-based materials with (3‑Glycidyloxypropyl)trimethoxysilane (GPTMS) (Epx-SiO) and activation with glycine (Gly-Epx-SiO) in order to immobilize lipase from Thermomyces lanuginosus (TLL) via adsorption. Rice husk silica (RHS) was selected as support with the aim of comparing its performance with commercial silica (Immobead S60S). Sequential functionalization/activation of SiO-based supports has been confirmed by AFM, SEM and N adsorption-desorption analyses.