RESUMEN

A low-cost and sensitive amperometric biosensor was developed for the determination of α-amylase activity. The biosensor was constructed by immobilizing glucose oxidase-gelatin via glutaraldehyde on the Au electrode surface. Measurements were carried out chronoamperometrically at -0.7 V. Several parameters such as glucose oxidase activity, gelatin amount, and glutaraldehyde percentage for cross-linking were optimized. Optimum pH, optimum temperature, repeatability, and storage stabilities of the biosensor were identified. Under the optimum experimental conditions, a linear calibration curve was obtained for α-amylase between 0.819 and 13.110 U/ml. Sample analyses were carried out by detecting α-amylase activities in baker's yeast samples.

Asunto(s)

Técnicas Biosensibles/métodos , Electroquímica/métodos , Oro/química , alfa-Amilasas/metabolismo , Aspergillus niger/enzimología , Bacillus subtilis/enzimología , Electrodos , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Glucosa/metabolismo , Glucosa Oxidasa/química , Glucosa Oxidasa/metabolismo , Glutaral/metabolismo , Concentración de Iones de Hidrógeno , Hidrólisis , Modelos Lineales , Oxígeno/metabolismo , Almidón/metabolismo , Propiedades de Superficie , Temperatura