An electronic device based on gold nanoparticles and tetraruthenated porphyrin as an electrochemical sensor for catechol

• Main Authors: Luana M. Sousa, Luana M. Vilarinho, Gabriel H. Ribeiro, André L. Bogado, Luís R. Dinelli
• Format: Article
• Language: English
• Published: The Royal Society 2017-01-01
• Series: Royal Society Open Science
• Subjects: dihydroxybenzene; electrode modified; electropolymerization; cobalt porphyrin
• Online Access: https://royalsocietypublishing.org/doi/pdf/10.1098/rsos.170675

The aim of this study was to obtain an electrochemical device between the electrostatic interaction of the electropolymerized porphyrin {CoTPyP[RuCl3(dppb)]4}, where TPyP = 5,10,15, 20-tetrapyridilphorphyrin and dppb = 1,4-bis(diphenylphosphino)butane, and gold nanoparticles (AuNPsn−), to be used as a voltammetric sensor to determine catechol (CC). The modified electrode, labelled as [(CoTPRu4)n8+-BE]/AuNPsn− {where BE = bare electrode = glassy carbon electrode (GCE) or indium tin oxide (ITO)}, was made layer-by-layer. Initially, a cationic polymeric film was generated by electropolymerization of the {CoTPyP[RuCl3(dppb)]4} onto the surface of the bare electrode to produce an intermediary electrode [(CoTPRu4)n8+-BE]. Making the final electronic device also involves coating the electrode [(CoTPRu4)n8+-BE] using a colloidal suspension of AuNPsn− by electrostatic interaction between the species. Therefore, a bilayer labelled as [(CoTPRu4)n8+-BE]/AuNPsn− was produced and used as an electrochemical sensor for CC determination. The electrochemical behaviour of CC was investigated using cyclic voltammetry at [(CoTPRu4)n8+-GCE]/AuNPsn− electrode. Compared to the GCE, the [(CoTPRu4)n8+-GCE]/AuNPsn− showed higher electrocatalytic activity towards the oxidation of CC. Under the optimized conditions, the calibration curves for CC were 21–1357 µmol l−1 with a high sensitivity of 108 µA µmol l−1 cm−2. The detection limit was 1.4 µmol l−1.