Chair Professor, University of Chinese Academy of Sciences
地 点: 吕志和楼B101报告厅
主持人: 齐志 研究员 毛晟 研究员
Liquid--liquid phase separation has emerged as one of the important paradigms in the chemical physics as well as biophysics of charged macromolecular systems. We elucidate an equilibrium phase separation mechanism based on charge regulation, i.e., protonation-deprotonation equilibria controlled by pH, in an idealized macroion system which can serve as a proxy for simple coacervation. First, a low-density density functional calculation reveals the dominance of two-particle configurations coupled by ion adsorption on neighboring macroions. Then a binary cell model, solved on the Debye-Hückel as well as the full nonlinear Poisson-Boltzmann level, unveils the charge symmetry breaking as inducing the phase separation between low- and high-density phases as a function of pH. These results can be identified as a charge symmetry broken complex coacervation between chemically identical macroions.
Rudolf Podgornik is a CHair professor at the University of Chinese Academy of Sciences in Beijing. He received his PhD in theoretical phayics from the University of Ljubljana and did his postdoc at NIH, Bethesda, MD and Chemical center, University of Lund. He has published about 300 papers in refereed journals including 2 papers in Rev. Mod. Phys. amd 1 paper in Phys. Rep. His main research interests include physics of DNA, RNA and membranes; physical virology; Casimir and van der Waals interactions; Electrostatic correlation interactions