RESUMO
In this paper, a novel amperometric L-glutamate (Glu) biosensor with immobilization of L-glutamate oxidase (L-GlOx) on polypyrrole-polyvinylsulphonate (PPy-PVS) film has been successfully developed. L-GlOx enzyme was immobilized on PPy-PVS film by cross-linking with glutaraldehyde (GA) and bovine serum albumin (BSA). Determination of Glu was carried out by oxidation of enzymatically produced H2O2 at 0.3 V versus Ag/AgCl. The optimum pH and temperature parameters were found to be 9.0 and 55 °C, respectively. There were three linear parts in the regions between 1.0 × 10(-9) and 1.0 × 10(-8) M (R(2) = 0.847), 5.0 × 10(-8) and 5.0 × 10(-7) M (R(2) = 0.997), 5.0 × 10(-7) and 5.0 × 10(-5) M (R(2) = 0.994). Storage stability, operation stability of the enzyme electrode were also studied.
Assuntos
Aminoácido Oxirredutases/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas , Ácido Glutâmico/sangue , Polímeros/química , Polivinil/química , Pirróis/química , Ácidos Sulfônicos/química , Animais , Calibragem , Bovinos , Reagentes de Ligações Cruzadas/química , Eletrodos , Enzimas Imobilizadas , Glutaral/química , Humanos , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Sensibilidade e Especificidade , Soroalbumina Bovina/química , TemperaturaRESUMO
We have developed a strategy to immobilize ß-galactosidase as a model enzyme by using polymeric supports having Schiff bases, which were prepared from (aminomethyl)polystyrene and 2-phenlyindole-3-carboxaldehyde by condensation. ß-galactosidase was immobilized onto the new polymer supports via covalent bonds. The influence of temperature, pH, reusability, and storage capacity on the free and immobilized ß-galactosidase was investigated. Our results indicate that the (aminomethyl)polystyrene with Schiff bases is most suitable for the immobilization of ß-galactosidase. These kinds of new supports can be used for the immobilization of ß-galactosidase due to their strong storage capacity and reusability.