Emanuela Bianchi, "Modeling and simulating heterogeneously charged particles: from materials design to biological phenomena"

Tuesday 5 Nov 2024, 10:00 → 11:00 Europe/Ljubljana

Seminar room of physics (106) (IJS)

Globular proteins and recently synthesized colloids engineered with differently charged surface regions share a direction-dependent interaction characterized by a reduced bonding valence and a competition between like-charge attraction and opposite-charge repulsion. Understanding the large-scale behavior of heterogeneously charged particles is thus critical for exploring both biological processes, such as the liquid-liquid phase separation of globular proteins, and the assembly of target structures with specific properties at the nano- and micro-scale. 

Recently, we developed a simple coarse-grained model that, within well-defined limits, accurately reproduces the reference electrostatic potential derived from the linearized Poisson-Boltzmann framework [1]. This model is straightforward to implement in Monte Carlo and Molecular Dynamics (MD) simulations, enabling the exploration of how varying parameters -- such as net particle charge and surface charge pattern -- affect the self-assembly of these particles.

As illustrative examples, I will present our findings on how non-uniform electrostatics at the particle surface can influence the self-assembly of ordered phases [2] as well as the liquid-liquid phase separation [3].

[1] Soft Matter, 7, 8313 (2011), J.Chem. Phys., 142, 114905 (2015)
[2] Nanoscale, 9, 1956 (2017), Current Opinion in Colloid & Interface Science, 30, 18 (2017)
[3] arXiv:2401.10655, Soft Matter, 20, 7601(2024)