Cholesterol oxidase biosensors based on polymer networks of chitosan/alginic acid and chitosan/p(toluenesulfonicacid)

Yapar, Elif
By mixing different stoichiometric ratios of chitosan with alginic acid (AA) and chitosan with p(toluenesulfonicacid) (PTSA), two new polymer networks were prepared. FT-IR spectroscopy results show the protonation of chitosan by AA and PTSA. Elemental analysis (EA) results show the composition of the networks. Thermal gravimetry analysis (TGA) and differential scanning calorimetry (DSC) results were used to characterize the thermal stability of the networks. Then, cholesterol oxidase (ChOx) enzyme were immobilized in these networks and checked for potential use of these enzyme entrapped polymer networks (EEPN) for enzyme immobilization. Additionally, the maximum reaction rate (Vmax) and Michaelis-Menten constant (Km) were evaluated for immobilized ChOx in these two polymer networks. Also, temperature and pH optimization, operational stability, shelf-life and the proton conductivity of these networks were investigated.


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Citation Formats
E. Yapar, “Cholesterol oxidase biosensors based on polymer networks of chitosan/alginic acid and chitosan/p(toluenesulfonicacid),” M.S. - Master of Science, Middle East Technical University, 2012.