RT info:eu-repo/semantics/article T1 Biomimetic biosensor based on lipidic layers containing tyrosinase and lutetium bisphthalocyanine for the detection of antioxidants A1 Rodríguez Méndez, María Luz A1 Apetrei, Constantin A1 Alessio, Priscila A1 Constantino, Carlos José Leopoldo A1 Saja Sáez, José Antonio de A1 Pavinato, Felippe J. A1 Giuliani, E. A1 Zucolotto, V. A1 Oliveira, Osvaldo N. AB This paper describes the preparation of a biomimetic Langmuir-Blodgett film of tyrosinase incorporated in a lipidic layer and the use of lutetium bisphthalocyanine as an electron mediator for the voltammetric detection of phenol derivatives, which include one monophenol (vanillic acid), two diphenols (catechol and caffeic acid) and two triphenols (gallic acid and pyrogallol). The first redox process of the voltammetric responses is associated with the reduction of the enzymatically formed o-quinone and is favoured by the lutetium bisphthalocyanine because significant signal amplification is observed, while the second is associated with the electrochemical oxidation of the antioxidant and occurs at lower potentials in the presence of an electron mediator. The biosensor shows low detection limit (1.98×10(-6)-27.49×10(-6) M), good reproducibility, and high affinity to antioxidants (K(M) in the range of 62.31-144.87 μM). The excellent functionality of the enzyme obtained using a biomimetic immobilisation method, the selectivity afforded by enzyme catalysis, the signal enhancement caused by the lutetium bisphthalocyanine mediator and the increased selectivity of the curves due to the occurrence of two redox processes make these sensors exceptionally suitable for the detection of phenolic compounds. SN 0956-5663 YR 2011 FD 2011 LK http://uvadoc.uva.es/handle/10324/30776 UL http://uvadoc.uva.es/handle/10324/30776 LA eng NO Biosensors and Bioelectronics vol. 26 p. 2513-2519 NO Producción Científica DS UVaDOC RD 29-mar-2024