desolvation

Desolvation is the removal of solvent molecules from a solute or solution, resulting in a less solvated or nonsolvated species. It can refer to processes in chemistry where a dissolved substance becomes separated from the solvent, often by evaporation, distillation, or chemical reactions that release solvent molecules.

In inorganic and coordination chemistry, desolvation often occurs when a solvent molecule is displaced or when a solution is dried to obtain solid salts or coordination compounds with reduced solvent inclusion. In biochemistry, desolvation describes the precipitation of proteins or other macromolecules by adding a non-solvent or by changing solvent conditions.

Common methods include evaporation under ambient or reduced pressure, drying under vacuum, and freeze-drying (sublimation of solvent). Solvent exchange or non-solvent precipitation also achieves desolvation, as the solute becomes less compatible with the new solvent and precipitates.

Desolvation is used as a synthesis strategy for nanoparticles and polymers. The desolvation method involves adding a miscible desolvating agent to a polymer solution, causing phase separation and particle formation; followed by crosslinking to stabilize particles. Albumin nanoparticles prepared by desolvation are an example used in drug delivery.

In analytical chemistry, desolvation occurs in mass spectrometry and other instrumental techniques during sample introduction, where solvent is removed from ions or droplets, enabling formation of gas‑phase ions. Desolvation efficiency influences sensitivity and peak shape.