title: Monitoring of malolactic fermentation in wine using an electrochemical bienzymatic biosensor for L-lactate with long term stability.
abstract: L-lactic acid is monitored during malolactic fermentation process of wine and its evolution is strongly related with the quality of the final product. The analysis of L-lactic acid is carried out off-line in a laboratory. Therefore, there is a clear demand for analytical tools that enabled real-time monitoring of this process in field and biosensors have positioned as a feasible alternative in this regard. The development of an amperometric biosensor for L-lactate determination showing long-term stability is reported in this work. The biosensor architecture includes a thin-film gold electrochemical transducer selectively modified with an enzymatic membrane, based on a three-dimensional matrix of polypyrrole (PPy) entrapping lactate oxidase (LOX) and horseradish peroxidase (HRP) enzymes. The experimental conditions of the biosensor fabrication regarding the pyrrole polymerization and the enzymes entrapment are optimized. The biosensor response to L-lactate is linear in a concentration range of 1 × 10(-6)-1 × 10(-4) M, with a detection limit of 5.2 × 10(-7) M and a sensitivity of - (13500 ± 600) μA M(-1) cm(-2). The biosensor shows an excellent working stability, retaining more than 90% of its original sensitivity after 40 days. This is the determining factor that allowed for the application of this biosensor to monitor the malolactic fermentation of three red wines, showing a good agreement with the standard colorimetric method.
authors.affiliation: Instituto de Microelectrónica de Barcelona (IMB-CNM), CSIC, Campus UAB, 08193 Bellaterra, Spain.
authors.forename: Pablo
authors.initials: P
authors.lastname: Giménez-Gómez
authors.affiliation: Instituto de Microelectrónica de Barcelona (IMB-CNM), CSIC, Campus UAB, 08193 Bellaterra, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Gutiérrez-Capitán
authors.affiliation: Institut Català de la Vinya i el Vi (IRTA-INCAVI), Plaça Àgora 2, 08720 Vilafranca del Penedès, Spain.
authors.forename: Fina
authors.initials: F
authors.lastname: Capdevila
authors.affiliation: Institut Català de la Vinya i el Vi (IRTA-INCAVI), Plaça Àgora 2, 08720 Vilafranca del Penedès, Spain.
authors.forename: Anna
authors.initials: A
authors.lastname: Puig-Pujol
authors.affiliation: Instituto de Microelectrónica de Barcelona (IMB-CNM), CSIC, Campus UAB, 08193 Bellaterra, Spain.
authors.forename: César
authors.initials: C
authors.lastname: Fernández-Sánchez
authors.affiliation: Instituto de Microelectrónica de Barcelona (IMB-CNM), CSIC, Campus UAB, 08193 Bellaterra, Spain. Electronic address: cecilia.jimenez@csic.es.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Jiménez-Jorquera
mesh_terms: D015374:Biosensing Techniques; D005285:Fermentation; D006735:Horseradish Peroxidase / Q000378:metabolism; D019344:Lactic Acid / Q000378:metabolism*; D006899:Mixed Function Oxygenases / Q000378:metabolism; D014920:Wine
chemical_list: D019344:Lactic Acid; D006899:Mixed Function Oxygenases; D006735:Horseradish Peroxidase; C021497:lactate 2-monooxygenase
keywords: Amperometric biosensor; Bienzymatic membrane; Electrosynthesized polypyrrole; Malolactic fermentation; Wines; l-lactic acid analysis