biostudies-literatureRidwan MGKing Abdullah University of Science and Technology1852-1860https://www.ebi.ac.uk/biostudies/studies/S-EPMC8900129biostudies-literatureUnknown126(8)The role of ionic electrostatics in colloidal processes is well-understood in natural and applied contexts; however, the electrostatic contribution of zwitterions, known to be present in copious amounts in extremophiles, has not been extensively explored. In response, we studied the effects of glycine as a surrogate zwitterion, ion, and osmolyte on the electrostatic forces between negatively charged mica-mica and silica-silica interfaces. Our results reveal that while zwitterions layer at electrified interfaces and contribute to solutions' osmolality, they do not affect at all the surface potentials, the electrostatic surface forces (magnitude and range), and solutions' ionic conductivity across 0.3-30 mM glycine concentration. We infer that the zwitterionic structure imposes an inseparabiThe journal of physical chemistry. BZwitterions Layer at but Do Not Screen Electrified Interfaces.PMC8900129BAS/1/1070-01-01Ridwan MGMaharjan NMishra HShrestha BRfalseZwitterions Layer at but Do Not Screen Electrified Interfaces.The role of ionic electrostatics in colloidal processes is well-understood in natural and applied contexts; however, the electrostatic contribution of zwitterions, known to be present in copious amounts in extremophiles, has not been extensively explored. In response, we studied the effects of glycine as a surrogate zwitterion, ion, and osmolyte on the electrostatic forces between negatively charged mica-mica and silica-silica interfaces. Our results reveal that while zwitterions layer at electrified interfaces and contribute to solutions' osmolality, they do not affect at all the surface potentials, the electrostatic surface forces (magnitude and range), and solutions' ionic conductivity across 0.3-30 mM glycine concentration. We infer that the zwitterionic structure imposes an inseparabi2022-01-01T00:00:00Z2022 Mar2025-04-05T22:58:15.552Z2025-04-05T22:58:15.552ZS-EPMC89001293519499510.1021/acs.jpcb.1c10388