ABSTRACT
Immobilization of invertase in conducting copolymer matrices of 3-methylthienyl methacrylate with pyrrole and thiophene was achieved by constant potential electrolysis using sodium dodecyl sulfate (SDS) as the supporting electrolyte. Polythiophene (PTh) was also used in entrapment process for comparison. Kinetic parameters, Michaelis-Menten constant, K(m), and the maximum reaction rate, V(max), were investigated. Operational stability and temperature optimization of the enzyme electrodes were also examined.
Subject(s)
Enzymes, Immobilized/chemistry , Polymethyl Methacrylate/chemistry , Thiophenes/chemistry , beta-Fructofuranosidase/chemistry , Electrochemistry , Enzymes, Immobilized/metabolism , Kinetics , Microscopy, Electron, Scanning , Pyrroles/chemistry , Sodium Dodecyl Sulfate/chemistry , Surface Properties , Temperature , beta-Fructofuranosidase/metabolismABSTRACT
Immobilization of invertase in thiophene-capped poly(methylmethacrylate)/polypyrrole matrices was achieved by constant potential electrolysis using different supporting electrolytes. Optimum reaction conditions such as substrate concentration, temperature, and pH for the enzyme electrodes were determined. The temperature and pH were found to be 60 degrees C and 4.8, respectively. The effect of supporting electrolyte on the enzyme activity revealed that SDS was the best in the immobilization procedure. Michaelis-Menten constant and the maximum reaction rate in PMMA/PPy matrices were of the order of that of pristine polypyrrole. However, in terms of repeated use, the copolymer matrices were superior to polypyrrole.