A oxidação eletroquímica da dopamina leva à deposição de filmes poliméricos sobre a superfície de eletrodos sólidos, diminuindo a atividade dos mesmos. No eletrodo de mercúrio o processo redox ocorre na região de potencial de oxidação do mercúrio. No entanto, na presença de compostos carboxílicos o voltamograma cíclico da dopamina, no eletrodo de mercúrio, é diferenciado e apresenta um novo produto eletroativo proveniente do processo de oxidação da dopamina. O presente trabalho descreve resultados preliminares sobre o comportamento eletroquímico da dopamina no eletrodo de mercúrio na presença de acetato, citrato e EDTA.

The electrochemical oxidation of dopamine leads to deposition of polymeric films on the surfaces of solid state electrodes, decreasing the electrode activity. With a mercury electrode, the oxidation of dopamine occurs in the potential region of mercury oxidation. However, in the presence of carboxylic compounds the cyclic voltammogram of dopamine is different and presents a new electroactive product resulting from the oxidation of dopamine. This work describes preliminary results for the electrochemical behavior of dopamine at the Hg-electrode in the presence of acetate, citrate and EDTA.

This paper reviewed the development and theoretical aspects of surface plasmon ressonance (SPR) technique and discusses this powerful sensor technology in the development of biosensors, as well as for the investigation of biological interactions and clinical assays. The SPR has been proven to be a valuable tool to investigate dynamic processes, such as adsorption, degradation, determination of dieletric properties, association/dissociation kinetics, affinity constants of specific ligand-ligate interactions, allowing real-time analysis at almost any surface. The SPR as a complementary technique alongside electrochemical methods is also presented.

The use of carbon fibers to develop new sensors and biosensors has received great attention due to its characteristics and electrochemical properties. A brief presentation about history, properties, characteristics, composition and structure of the carbon fibers are shown in this paper. Several applications of the carbon fibers in electroanalytical chemistry for determination of metals and organic molecules in environmental and clinical samples are also described.