állófázis

Állófázis refers to a concept in chromatography, a technique used to separate components of a mixture. It describes the stationary phase, which is one of the two phases involved in the separation process. The stationary phase does not move with the mobile phase, which is the solvent or gas that carries the mixture through the system.

The nature of the stationary phase is crucial in determining the separation. It can be a solid material, a liquid coated onto a solid support, or a gel. Different types of stationary phases are designed to interact with specific types of molecules in the mixture. These interactions can be based on polarity, size, charge, or affinity.

In gas chromatography (GC), the stationary phase is typically a liquid coated on the inside of a capillary column or on solid particles packed into a column. In liquid chromatography (LC), the stationary phase is usually solid particles packed into a column, with a liquid mobile phase flowing through them. The stationary phase can be polar, nonpolar, or ion-exchange based, depending on the separation requirements.

The choice of stationary phase is critical for achieving effective separation. By carefully selecting a stationary phase that has different affinities for the components of a mixture, chromatographers can achieve resolution and analyze the individual substances. The interactions between the analytes and the stationary phase, along with the mobile phase, drive the separation process.