Calculation and Uncertainty of Zeta Potentials of Microorganisms in a 1:1 Electrolyte with a Conductivity Similar to Surface Water

Publication date: Available online 18 October 2019Source: Colloids and Surfaces A: Physicochemical and Engineering AspectsAuthor(s): Amy L. Polaczyk, James E. Amburgey, Amir Alansari, Jordan C. Poler, Marco Propato, Vincent R. HillAbstractThe electrophoretic mobilities (EPM’s) of fifteen different microbes (6 viruses, 5 vegetative bacteria, 2 bacterial endospores, 2 protozoa) and one microbial particle surrogate (Polystyrene microspheres) were measured, and five models were used to convert EPM's of these microorganisms to zeta potentials. The Helmholtz-Smoluchowski, Hückel-Onsager, Henry, modified Booth, and O’Brien and Hunter models were compared over their ranges of applicability for various microbes in a weak electrolyte solution intended to simulate the conductivity of surface water. The results from each of the models were compared by assessing the magnitude of the error due to inherent limitations of the models and comparing it to the error associated with the measurement of the EPM. Results indicated that differences imparted to the calculated zeta potentials by double layer distortion corrections were typically smaller than the uncertainty of the EPM measurement from which the zeta potential value was calculated. Based on our analyses, the Helmholtz-Smoluchowski equation was most appropriate for application to bacteria (vegetative and endospores) and parasites, while the Henry or modified Booth models were necessary for viruses. Zeta potential calculations with c...
Source: Colloids and Surfaces A: Physicochemical and Engineering Aspects - Category: Chemistry Source Type: research