文摘
The utility of various synthetic hectorites for the preparation of active enzyme complexesby simple adsorption processes was examined. The smectites compared include commerciallyavailable Laponite RD, mesostructured hectorites (both with and without organic template),and silane-modified mesostructured hectorite. The complexes were evaluated by the amountof cytochrome c that was incorporated and the fraction of enzyme available for redox reaction.The quantity of adsorbed cyt c was determined by optical absorption spectroscopy of thesupernatant solution, yielding enzyme densities that ranged from 20 to 50 wt %. There wasno correlation between weight percent loading and either the surface area or the pore volumeof the clay mineral. Rather, other characteristics such as surface compatibility appear toplay the major role in this regard. Immobilized enzyme conformation was examined by EPR.Qualitative information regarding protein stability and redox activity was also obtained bychemical reduction experiments. These studies revealed the effects of organo-tailoring ofthe inorganic surface in terms of steric hindrance of enzyme in active conformation anddenaturation within a clay pore microenvironment.