title: Automatic bionalyzer using an integrated amperometric biosensor for the determination of L-malic acid in wines.
abstract: A new automatic bioanalyzer for L-malic acid using an integrated amperometric biosensor as detector is reported for the first time in this work. The biosensor is constructed by gold film sputtering deposition on a stainless steel disk electrode and co-immobilization of the enzymes malate dehydrogenase (MDH) and diaphorase (DP) together with the redox mediator tetrathiafulvalene (TTF) by means of dialysis membrane. The analytical performance of the biosensor was evaluated when it was used as amperometric detector in three different analytical methodologies: stirred solutions, semiautomatic FIA system and automatic bioanalyzer. The bienzyme biosensor exhibited great analytical performance in terms of sensitivity, selectivity and reproducibility of the measurements and its usefulness was demonstrated by analyzing wine reference materials with certified content of L-malic acid. The attractive analytical and operational characteristics demonstrated by the automatic bioanalyzer make it a promising simple, rapid and field-based tool for routine wine and fruit control.
authors.affiliation: Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, Avda. Complutense s/n, 28040 Madrid, Spain; InBea Biosensores S.L. Parque Científico de Madrid, C/ Santiago Grisolía 2, 28760 Tres Cantos, Madrid.
authors.forename: E
authors.initials: E
authors.lastname: Vargas
authors.affiliation: InBea Biosensores S.L. Parque Científico de Madrid, C/ Santiago Grisolía 2, 28760 Tres Cantos, Madrid.
authors.forename: M A
authors.initials: MA
authors.lastname: Ruiz
authors.affiliation: Departamento de Ingeniería electrónica, Universidad de Oviedo, Gijón, Spain.
authors.forename: F J
authors.initials: FJ
authors.lastname: Ferrero
authors.affiliation: Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, Avda. Complutense s/n, 28040 Madrid, Spain.
authors.forename: S
authors.initials: S
authors.lastname: Campuzano
authors.affiliation: Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, Avda. Complutense s/n, 28040 Madrid, Spain.
authors.forename: V
authors.initials: V
authors.lastname: Ruiz-Valdepeñas Montiel
authors.affiliation: Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, Avda. Complutense s/n, 28040 Madrid, Spain.
authors.forename: A J
authors.initials: AJ
authors.lastname: Reviejo
authors.affiliation: Departamento de Química Analítica, Facultad de CC. Químicas, Universidad Complutense de Madrid, Avda. Complutense s/n, 28040 Madrid, Spain. Electronic address: pingarro@quim.ucm.es.
authors.forename: J M
authors.initials: JM
authors.lastname: Pingarrón
mesh_terms: D015374:Biosensing Techniques; D004800:Enzymes, Immobilized / Q000737:chemistry; D006571:Heterocyclic Compounds / Q000737:chemistry; D008291:Malate Dehydrogenase / Q000737:chemistry; D008293:Malates / Q000032:analysis* / Q000737:chemistry; D009245:NADH Dehydrogenase / Q000737:chemistry; D014920:Wine / Q000032:analysis*
chemical_list: D004800:Enzymes, Immobilized; D006571:Heterocyclic Compounds; D008293:Malates; C030298:malic acid; D008291:Malate Dehydrogenase; C030574:malate dehydrogenase (decarboxylating); D009245:NADH Dehydrogenase; C063887:tetrathiafulvalene
keywords: Amperometric detection; Automatic bioanalyzer; Enzymatic biosensor; L-malic acid; Reference standards for wine samples