Determinación de arsénico en soluciones acuosas mediante voltamperometría de redisolución anódica combinada con onda cuadrada

Abstract

The contamination by arsenic is notorious and one of the most significant hazards globally that affects the environment. In low levels it affects the health being a co-carcinogen, it has been shown to be susceptible to the brain, and also worrying because it can cross the placenta retarding the growth of the fetus and causing defects in the neural tube. The different electrochemical techniques are important to determine or detect arsenic, as it an easy, effective and above all low cost method compared to conventional methods; therefore the objective of this research was to determine and validate the square wave voltammetry technique of anodic redissolution to determine arsenic in aqueous solutions, it is the most suitable technique used in experimental investigations since it determines traces of heavy metals with a limit of detection of 10-10 to 10-12 mol/L stipulated in the standards levels of the World Health Organization. By means of a systematic sampling it was decided that the voltammetry of anodic redissolution combined with square wave is an effective technique. Buffers and auxiliary solutions for experimental research were used to develop our thesis. We started with the weighing of several reagents (Sodium Acetate Trihydrate, Sodium Phosphate Monobasic, Dibasic Sodium Phosphate) of the preparation of the respective buffers. In the methodological systematization after having tested the pH and the preconcentration time, the various modifications and conventional and screen-printed electrodes were continued; the less favorable methodology was discarded after having tested in various electrochemical conditions. After obtaining better results combining electrochemical techniques, electrolytic media and electrochemical sensors with their respective modifications, favorable results were obtained as desired in the investigation.