DEVELOPMENT AND CREATION OF A ZETA POTENTIAL REFERENCE MATERIAL OF PARTICLES IN A LIQUID MEDIUM

摘要

A comprehensive study to develop and create standard samples of the zeta potential unit of particles in a liquid in accordance with the requirements of GOST ISO 13099-2-2016 in the range of measured values from -150 mV to +150 mV was carried out. The existing standard samples of the zeta potential in Russia and the world have been investigated; an analysis of the applicability of the starting materials and components for the creation of new standard samples is given. Samples based on modified polystyrene latex microspheres, bovine serum albumin and supramolecular systems based on aqueous solutions of L-cysteine, N-acetylcysteine, and silver acetate are considered as promising standard samples of the zeta potential of particles. All studies were carried out on equipment from the State Primary Standard of dispersed parameters of aerosols, suspensions and powder materials, GET 163-2020, by electrophoretic light scattering and pH measurement. It was found that polystyrene latex microspheres do not meet the requirements of the task in terms of developing a set of standard samples. Samples based on suspensions of bovine serum albumin do not meet the requirements of GOST ISO 13099-2-2016. Supramolecular systems based on aqueous solutions of L-cysteine, N-acetylcysteine, and silver acetate are proposed as standard samples. Such systems are characterized by the ability to modify the initial potential-determining layer of particles without changing their aggregate stability. Studies of the long-term stability of the developed standard samples of the zeta-potential unit of particles in a liquid have been carried out.