chromatography.docx

Chromatography is based on the principle where molecules in mixture applied onto the surface or into the solid, and fluid stationary phase (stable phase) is separating from each other while moving with the aid of a mobile phase. The factors effective on this separation process include molecular char...

Chromatography is based on the principle where molecules in mixture applied onto the surface or into the solid, and fluid stationary phase (stable phase) is separating from each other while moving with the aid of a mobile phase. The factors effective on this separation process include molecular characteristics related to adsorption (liquid-solid), partition (liquid-solid), and affinity or differences among their molecular weights. Because of these differences, some components of the mixture stay longer in the stationary phase, and they move slowly in the chromatography system, while others pass rapidly into mobile phase, and leave the system faster. Stationary phase: **Stationary phase:** This phase is always composed of a "solid" phase or "a layer of a liquid adsorbed on the surface a solid support". **Mobile phase:** This phase is always composed of "liquid" or a "gaseous component." Types of chromatography - Column chromatography - Ion-exchange chromatography - Paper chromatography - Thin-layer chromatography - Gas chromatography - High-pressure liquid chromatography (HPLC)