ABSTRACT
Vitamins are defined as biologically active organic compounds, controlling agents that are essential for an organism’s normal health and growth, not synthesized within the organism, available in the diet in small amounts, and carried in the circulatory system in low concentrations to act on target organs or tissues. Vitamins are classified according to their solubility in water and in fats. Lipophilic vitamins are vitamins A, D, E, and K. Chromatography is useful in the identification and determination of vitamins in pharmaceutical preparations, the identification and determination of vitamins and related substances in natural materials and foodstuffs, and the chemical and biochemical determination of vitamins and their metabolites in fats and tissues. The isolation of the vitamins, their metabolites, and related substances from natural material is the most difficult task (1-4). Vitamins that are soluble in fat (lipophilic vitamins) are the object of wide investigations because of their biological properties. HPLC, TLC, and GC are the principal techniques used for the qualitative and quantitative investigations of lipophilic vitamins. Analysis of lipophilic vita¬ mins by liquid chromatography (TLC and HPLC) is the subject of many scientific publications d-18).
