Analytical method of direct derivatization of fatty acids in seeds

The combination of the lipid extraction method followed by derivatization leads to extensive manipulation of the sample which may lead to increased experimental errors. In view of this, the work proposes the development of a direct derivatization method of fatty acids in seed samples using the response surface methodology. The use of an experimental design procedure (Design Expert software) allows the optimization of the alkaline and acid reaction times. The procedure was validated for 5 min in both steps. The method was validated for sunflower, canola and corn seed. The results for the merit figures of accuracy (from 99.76 to 101.23%), precision RSD intra-day (from 0.74 to 1.25%) RSD inter-day (from 1.34 to 3.47%), linearity (R2 = 0.9865), and robustness confirmed that the new method is satisfactory within the application range of 5–40% of lipids in the sample.