An improved biosensor for acetaldehyde determination using a bienzymatic strate...

• Autor(es): Ghica, Mariana Emilia ; Pauliukaite, Rasa ; Marchand, Nicolas ; Devic, Eric ; Brett, Christopher M.A.
• Data: 2007
• Identificador Persistente: http://hdl.handle.net/10316/5045
• Origem: Estudo Geral - Universidade de Coimbra
• Assunto(s): Nicotinamide adenine dinucleotide oxidase; Aldehyde dehydrogenase; Carbon film electrode; Poly(neutral red); Enzyme cross-linking; Sol-gel
• Tipo de Documento: Artigo
• Idioma: Inglês

Descrição

Improved biosensors for acetaldehyde determination have been developed using a bienzymatic strategy, based on a mediator-modified carbon film electrode and co-immobilisation of NADH oxidase and aldehyde dehydrogenase. Modification of the carbon film electrode with poly(neutral red) mediator resulted in a sensitive, low-cost and reliable NADH detector. Immobilisation of the enzymes was performed using encapsulation in a sol-gel matrix or cross-linking with glutaraldehyde. The bienzymatic biosensors were characterized by studying the influence of pH, applied potential and co-factors. The sol-gel and glutaraldehyde biosensors showed a linear response up to 60 [mu]M and 100 [mu]M, respectively, with detection limits of 2.6 [mu]M and 3.3 [mu]M and sensitivities were 1.7 [mu]A mM-1 and 5.6 [mu]A mM-1. The optimised biosensors showed good stability and good selectivity and have been tested for application for the determination of acetaldehyde in natural samples such as wine. http://www.sciencedirect.com/science/article/B6TF4-4NBH223-4/1/df3a7ae65fbb5f9739654441b2c733ed