Fusion of Biomolecular Condensates

A popular approach to determine the interfacial tension of liquid-like macromolecular condensates is to measure the dynamics of coalescence of two droplets. While this is conceptually straightforward and seemingly simple to implement, it can be challenging to accurately determine the physical properties, as rates of fusion can be strongly affected by contact line dynamics. To identify the limitations of this technique, we compare the dynamics of fusion for droplets in contact with a surface to droplets in the bulk of a solution. We compare the resulting values of the capillary velocity to that determined through independent measurements of the surface tension by sessile drop tensiometry and particle tracking microrheology (Ijavi arXiv 2020).