Abstract
A reversed phase high-performance liquid chromatographic method (HPLC) is described for separation and determination of colecalciferol (Vitamin D3) in Vitamin preparations and in biological materials. Vitamin D3 is extracted from the formulations and from the blood in a fully automated electronically controlled extraction apparatus. For HPLC a column of lichrosorb RP18 and methanol as eluent are used. The extraction, separation and determination of vitamin D3 needs about 10–20 minutes. The described extraction and HPLC methods allow the detection of 1–2 ng per injection and are well reproduced with a maximum coefficient of variation of < 3,5%. Vitamin A-acetate is used as internal standard.