β-Cyclodextrin electropolymerization: mechanism, electrochemical behavior, and optimization

The main purpose of this manuscript was to study the electropolymerization using cyclodextrin as a monomer for application as electrochemical sensors. This process was first studied by Morales et al. and will be discussed in this work using a systematic and descriptive approach. For that, the voltammetric behavior of a -cyclodextrin electropolymerization on a carbon glassy electrode (CGE) surface and the mechanism involved was investigated. The electropolymerization exhibits two anode peaks at 0.61V and 1.56 and two cathode peaks at -0.58V and -1.05 that increases in successive cycles, indicating that a -CD polymer film is being formed. The mechanism of -CD electropolymerization occurs in two stages simultaneously: the monomer is deposited on the surface of the CGE by covalent bonds, while the monomer is coupled successively producing the polymer. The followed experimental conditions were optimized evaluating the voltammetric responses observed during the polymer formation: potential range (-1.3 to 0.9V), presence or absence of dissolved oxygen (presence) and stirring during the electropolymerization (with agitation), electrolyte pH (pH=5.0), scan rate (100mVs(-1)), and concentration of -CD (6mol L-1). The optimization promoted the development of a more efficiently synthesis. [GRAPHICS]