Differential double pulse voltammetry (DDPV) and additive differential pulse voltammetry (ADPV) applied to the study of
- PDF / 1,061,254 Bytes
- 13 Pages / 595.276 x 790.866 pts Page_size
- 20 Downloads / 222 Views
ORIGINAL PAPER
Differential double pulse voltammetry (DDPV) and additive differential pulse voltammetry (ADPV) applied to the study of the ACDT mechanism José Manuel Olmos 1 & Eduardo Laborda 2 & Angela Molina 2 Received: 9 April 2020 / Revised: 21 April 2020 / Accepted: 23 April 2020 # Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract The value of double potential pulse differential techniques for electrochemical studies of dynamic chemical speciation is investigated within the context of liquid|liquid electrochemistry. Then, not only information about the speciation thermodynamics and kinetics is accessible, but also about the species lipophilicity. This provides a comprehensive view of their behaviour in natural and biological media. With the above aim, the current-potential response of the ACDT mechanism (aqueous complexation-dissociation coupled to transfer), where two chemically linked species can transfer between a hydrophilic and a lipophilic phase, is modelled in differential double pulse voltammetry (DDPV) and additive differential pulse voltammetry (ADPV). Explicit closed-form expressions are deduced for both techniques at liquid|liquid macrointerfaces, applicable to any charge number and lipophilicity of the species. The DDPV and ADPV signals are shown to be well sensitive to the features of the chemical reaction, as well as to the species charge and lipophilic character. Also, these techniques offer higher resolution and discrimination against superimposed signals than direct-current techniques, together with high sensitivity and minimization of capacitive effects and background currents, which are key advantages for accurate quantitative analysis. Keywords ACDT mechanism . Additive differential pulse voltammetry . Differential double pulse voltammetry . Liquid|liquid electrochemistry . Chemical speciation
Introduction Chemical speciation, mass transport and lipophilicity are key aspects to understand and predict the dynamic behaviour of compounds in natural media, biological fluids and food. They affect the (bio)availability and (bio)uptake of chemical species, determining their toxic or beneficial activity [1–8], as well as the efficiency of industrial processes [4, 9, 10]. Thus, Electronic supplementary material The online version of this article (https://doi.org/10.1007/s10008-020-04619-w) contains supplementary material, which is available to authorized users. * Angela Molina [email protected] 1
Centro de Investigação em Química da Universidade do Porto, Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, Porto, Portugal
2
Departamento de Química Física, Facultad de Química, Regional Campus of International Excellence “Campus Mare Nostrum”, Universidad de Murcia, 30100 Murcia, Spain
accurate methods for the analysis of dynamic speciation and phase transfer processes are of utmost importance. In the case of ionic compounds, the aspects above mentioned can be studied simultaneously making use of the methodologies provided by biomimetic liquid|li
Data Loading...
