Software development for calculating concentration in a buffer to the preparation of background electrolyte in the analytical method of capillary electrophoresis

Abstract

pH buffers of weak organic acids and bases are essential in capillary electrophoresis (CE) analyses, primarily when contactless conductivity detectors (C⁴D) are used. However, the preparation of a buffer with a known concentration of one component for use as a background electrolyte (BGE) in CE-C⁴D usually requires a pH adjustment to the desired value and an approximate calculation to estimate the concentration of the second component. This study developed software that allowed determining the concentration of one component when knowing the concentration of another component and the pH of the solution, taking into account the influence of ionic strength. The software was built in C# language with Windows Form interface on Microsoft Visual Studio. With the concentrations calculated from the developed software, the differences (|ΔpH|) between pH values of the obtained BGEs in practice and the desired values were smaller than 0.07, corresponding to the errors of less than 2%.