Preparation of Nano-porous Silica Aerogel and Its Application to a Bio-conversion Process

Jong-Kil KIM, Jin-Koo PARK, Ho-Kun KIM

Bio-conversion processes utilizing an immobilized biocatalyst (enzyme) are widely used to synthesize various kinds of medicines or intermediates of ones. The support for enzyme, such as silica, plays an important role in the overall yield of the bio-conversion reaction because the yield is depended on loading capacity of enzymes. In this study, nano-porous silica aerogel and xerogel, suitable for support of enzyme were synthesized via a salt route and the pore morphology, formed in silica, was characterized. Then, Penicillin G-amidase, the enzyme for the bio-conversion process to synthesize an antibiotic, was immobilized on the prepared porous silica and the loading efficiency was investigated in relation to the kinds of silica. As a result, silica aerogel showed much higher loading capacity (83 Units/g) of enzyme then that of xerogel (26 Units/g).

Key words: Nano-porous silica, Xerogel, Aerogel, Bio-conversion, Enzyme immobilization