Hollow Silica Nanotubes For Immobilization Of Glucose Oxidase Enzyme And Macroreticular Chelating Resins Containing Amidoxime Groups For Immobilization Penicillin Acylase

Molecular imprinting is a new and potential separation technique for To realize a low cost, easy scale-up synthesis process and application for hollow silica materials, a novel preparation route was presented to fabricate microporous hollow silica nanoparticles with controllable morphologies and wall thickness via core/shell structure of CaCO₃/SiO₂ by adopting sodium silicate as silica source in a sol-gel route, followed by calcination and acid etching process. a novel organic-inorganic double-template method was developed to synthesize hollow silica nanoparticles with mesoporous shells. By introducing CTAB as a pore channel directing agent and utilizing TEOS as organic silica source, mesoporous hollow silica nanospheres and nanotubes with good morphologies were successfully obtained.When the Glucose Oxidase enzyme were immobilized on the Hollow silica nanotubes, the effects of various immobilizing on the apparent activity and recovery ratio of activity of immobilized penicillin acylase were examined, such as the different phase,pH,time,temperature and the used amount of enzyme. The appropriate immobilization conditions are as follows: water of phase; 6.5 of pH; 28℃of temperature; 4⁶h of time and 0.6g/ml of ratio.For examining the properties of immobilized Glucose Oxidase enzyme, suitable pH and temperature of free enzyme and immobilized enzyme catalysis reaction was examined, continued operation stability, thermal stability and storage stability was studied, at the same time, michaelis-menten constant of free enzyme and immobilized enzyme were also measured. The experiment results showed: the optimum pH of enzyme catalysis reaction were 5.6 and 5.2, the optimum temperature were 28℃and 32℃for free enzyme and immobilized enzyme, respectively. The immobilized enzyme is more stable than free enzyme and michaelis-menten constant of immobilized enzyme and free enzyme were 28.7×10^-2 mol/L and 15.6×10^-2 mol/L.There are brief introduction of Macroreticular chelating resins containing amidoxime groups, which was used to be carrier of immobilizing Penicillin acylase. The effects of various immobilizing penicillin acylase were examined, such as pH,temperature and operation stability and storage stability. The experiment results showed: the optimum pH of enzyme catalysis reaction were 9 and 8.5, the optimum temperature were 45℃and 50℃for free enzyme and immobilized enzyme, respectively. The immobilized enzyme is more stable than free enzyme.