The application of a novel Poly(3,4-ethylenedioxythiophene)-Tyrosinase/Sonogel-Carbon electrode (PEDOT-Tyr/SNGC) biosensor to beers and wines analysis is proposed. This biosensor implies a new Sinusoidal Current (SC) electrodeposition method to immobilize the enzyme generating a nanostructure surface. The biosensors were characterized electrochemically, employing cyclic voltammetry and electrochemical impedance spectroscopy. Sensitivity, limit of detection, and correlation coefficients of the linear fitting were 2.40 × 10−4 µA·µM−1, 4.33 µM, and R2 = 0.9987, respectively. Caffeic acid is used as the reference polyphenol. A sampling of nine beers (four lager, three stout, and two non-alcoholic beers), and four wines (three red and one white wine) purchased in a local store was performed. The Polyphenol indeces for beers and wines have been assessed using the proposed biosensor, and the obtained values are in agreement with the literature data. Antioxidant properties of the samples using the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical spectrophotometric method were also evaluated. The correlation between the polyphenol index and the antioxidant capacity was obtained for beers and wines.

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Conducting polymers (CPs) are extensively studied due to their high versatility and electrical properties, as well as their high environmental stability. Based on the above, their applications as electronic devices are promoted and constitute an interesting matter of research. This review summarizes their application in common electronic devices and their implementation in electronic tongues and noses systems (E-tongues and E-noses, respectively). The monitoring of diverse factors with these devices by multivariate calibration methods for different applications is also included. Lastly, a critical discussion about the enclosed analytical potential of several conducting polymer-based devices in electronic systems reported in literature will be offered.

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