The self-assembly of charged biological entities is a topic of fundamental importance in both fundamental and applied sciences. Our current understanding of how uniformly charged particles, ranging from the nano- to micron-scale, interact in polar solvents with dissolved salts largely relies on the mean-field framework, i.e. DLVO theory. While recent extensions of DLVO-like models have incorporated particles with non-uniform charge distributions, their applicability remains limited primarily to conditions involving higher concentrations of monovalent salts.
This talk aims to address the self-assembly behavior of anisotropically charged colloids in solutions that also contain polyvalent ions. It is well established that the strong coupling between polyvalent salts and macroions can give rise to unusual electrostatic phenomena, such as like-charge attraction. However, the impact of these interactions on the phase behavior of anisotropically charged colloidal suspensions remains poorly understood.
To tackle this complex problem, we begin with a simplified model of charged Janus colloids immersed in an asymmetric ionic environment. By employing a field-theoretic approach, we derive the effective electrostatic interactions, which can then be incorporated into coarse-grained models suitable for simulation studies.