Automation: Vapor Pressure

Synonyms

Vapor tension

Definition

Vapor pressure is broadly defined as the pressure that a vapor exerts when at equilibrium with its condensed phase. In the context of lipidomics, vapor pressure is commonly used to refer to the rate at which a liquid evaporates to achieve equilibrium, and a liquid with a high vapor pressure at room temperature is referred to as volatile. The volatile solvents used in lipid extraction span a wide range of vapor pressures but most are substantially higher than water, and this presents challenges in liquid handling. Vapor pressure has major considerations for automation; the most significant include volume changes due to evaporation and management of vapor pressure during pipetting steps. Rapid evaporation of solvent and concurrent increases in solute concentration due to high vapor pressure can be managed by lowering the temperature (and subsequent vapor pressure) of open containers and by minimizing both headspace and the equilibration of volatile...