The Use of Boron-Doped Diamond Electrode for the Determination of Selected Biocides in Water Samples

In recent years, the remains of chemical substances in water environments, referred to as emerging organic contaminations, have been more and more often studied by analysts. This work shows the possibility of using a boron-doped diamond electrode to determine low concentration levels of remains of pharmaceuticals in environmental samples. The study focused on selected biocides from the group of azole fungicides (itraconazole and posaconazole) and was performed using quick and sensitive electrochemical methods. The cyclic voltammetry method was used in order to determine the properties of these compounds, whereas analytical characterization was performed using square wave voltammetry. The work involved the specification of the optimum electrooxidation conditions of the selected fungicides, their comparative characterization, and the development of a new, sensitive methods of itraconazole and posaconazole assay. The proposed procedures allowed us to determine itraconazole in the range from 7.9 × 10−8 to 1.2 × 10−6 moL·L−1 and posaconazole in the range from 5.7 × 10−8 to 8.44 × 10−7 moL·L−1. The relative standard deviation of the measurements did not exceed 5.85%. The developed procedures were successfully used to determine itraconazole and posaconazole concentration in water samples and the assay recovery was between 93.5% and 102.8%.