Abstract
Purposeing for establishing a standard method for the gas chromatographic determination of fatty acid composition, collaborative study team has carried out a replicate analysis of specified samples by using gas chromatographs with flame ionization detectors, and examined the entire set of the experimental data by a statistical method. In the collaborative studies, standard mixtures containing five fatty acid methyl esters (C12 : 0, C14 : 0, C16 : 0, C18 : 0 and trans-C18 : 1) were used as samples for analyses.
Through three times of the collaborative studies, the conclusion obtained was as follows :
(1) The correction factors which showed a certain regularity for the analyses of four samples were observed in the results obtained by sixty percent of all laboratories. The deviations and interlaboratory scattering of these results could be reduced considerably by applying the correction. factors.
(2) For the determination of the correction factors, it is desirable to analyse known mixture having composition similar to that of the unknown sample using the same instrument under the same operating conditions as those for analysis of the unknown.
(3) By injecting constant amount of sample, intrrlaboratory scattering was decreased while interlaboratory scattering was not decreased. From this collaborative study it is recommended that a 0.5 to 1.0μl of 20% solution is to be injected.
