Validation of a method for gas chromatographic analysis of eicosapentaenoic acid and docosahexaenoic acid as active ingredients in medicinal products

Abstract

A gas chromatographic method for the determination of all‐cis‐5,8,11,14,17‐eicosapentaenoic acid (EPA) and all‐cis‐4,7,10,13,16,19‐docosahexaenoic acid (DHA) as active ingredients in medicinal products was developed and validated. In accordance with the rules governing medicinal products in the European Community, the method establishes relations between label claims of active ingredients and known reference standards. A routine for examining instrument status is proposed. The relative standard deviation was 1% (n=26) for determination of the empirical response factors of EPA ethyl ester and DHA ethyl ester relative to the internal standard, C23:0 methyl ester. This experiment included two columns and EPA and DHA standards from two different suppliers and was carried out over a five‐month period. Repeatability (n=6) for low and medium concentrates of glycerides and high concentrates of ethyl esters, expressed as coefficient of variation, was 4, 0.7 and 0.7%, respectively. Accuracy (n=6) determined as percent recovery was better than 98% for all sample types. Analytical results from a twelve‐month stability study of the high concentrate are shown.