Contribution to the standardisation of a gas chromatographic method for the analysis of an oestrogenic and progestational combination.
An experimental procedure is described in order to standardize a gaschromatographic method proposed for a collaborative study organised by the F.I.P. Committee for Laboratories and Official Drug Control Services, on the analysis of some oestro-progestinic formulations. The assayed combination was a standard mixture of lynestrenol, mestranol and d, 1-alpha-tocopherol: testosterone was included as internal standard; two combinations, differing only in the internal standard content as specified in the text, were used. The variability of the instrumental factor was investigated performing some sets of single experiments, each consisting of 5 successive injections of the same standard mixture, on the same day. For each single experiment and for each substance the mean value Rm of the ratios R (R=area of the peak for compound cpi/area of the peak of the internal standard) was estimated with its relative standard deviation (% s.d.). For each set of experiments the % s.d. values were elaborated, following the Bartlett test, in order to obtain the sigma intra % value for each set, as a measure of the instrumental factor. An experimental evidence was observed for the relationship existing between the instrumental factor value (sigma intra %) and the internal standard content, in the operating conditions fixed for the present gas chromatographic analysis, a lowering of the instrumental factor beeing observed with the higher level of testosterone content (internal standard) in the mixture.
D002849:Chromatography, Gas / Q000592:standards*; D004338:Drug Combinations; D004967:Estrogens / Q000032:analysis*; D008234:Lynestrenol / Q000032:analysis; D008656:Mestranol / Q000032:analysis; D011374:Progesterone / Q000032:analysis*; D013739:Testosterone / Q000032:analysis; D014810:Vitamin E / Q000032:analysis
D004338:Drug Combinations; D004967:Estrogens; D014810:Vitamin E; D013739:Testosterone; D011374:Progesterone; D008656:Mestranol; D008234:Lynestrenol