Fig. 6: Mechanism of spreading and wetting of spray droplets, and the charge residue model at interfaces.
From: Electrospray-assisted cryo-EM sample preparation to mitigate interfacial effects
a, Schematic representation of the evolution of electrified droplets in the ESI-cryoPrep equipment. b, Adjacent droplets form a water bridge and merge into a larger droplet through wetting effects. As droplets merge, their surface area decreases, resulting in a reduction of the total surface energy. c, The charge residue model at the AWI or GWI serves as a barrier, preventing direct interactions between protein particles and the opposing phase. Polar water solvents exhibit robust interactions with the charged droplet surface or the charged electrode. The radial charge gradient arises from mutual Coulombic repulsion among excess charges within the charge residue model of droplets. The top panel features legends for different ions.
