Analysis of grapes and wines using a voltammetric bioelectronic tongue. Correlation with the phenolic and sugar content

Abstract

Arrays of voltammetric sensors and biosensors based on phthalocyanines have been developed and used to analyze wines and grapes. Nanostructured sensors prepared by the Langmuir-Blodgett (LB), Layer by Layer (LbL) or electro-deposition are superior because the high number of active sites. The LB and the LbL techniques can be used to co-deposit electrocatalytic materials to obtain a synergistic electrocatalytic effect. Moreover, LB and LbL can be used to immobilize enzymes in a biomimetic structure formed by amphiphilic lipids. Such sensors show an enhanced selectivity. The presence of phthalocyanines as electron mediators improves the performance of the sensors. Combining sensors and biosensors in the same array provides the advantages of classical phthalocyanine based-sensors, with the specificity of the enzyme-substrate reaction typical of biosensors. The selectivity of the electronic tongue and its capability of discrimination are clearly improved when biosensors containing glucose oxidase or tyrosinase are included in the array.