USING A MOLECULAR INTERACTION-MODEL TO OP TIMIZE THE SEPARATION OF FATTY TRIGLYCERIDES IN CLPI - FINGERPRINTING THE DIFFERENT TYPES OF FATS

In reversed phase liquid chromatography, retention depends on both the stationary phase and the mobile phase. According to the nature of the stationary phase, the nature and the composition of the mobile phase, a lot of combinations can constitute the chromatographic system. Thus , the understanding of the retention mechanism becomes more difficult. A systematic study of retention of homologous series and triacylglyce rols gives the opportunity to distinguish between two retention mechan isms. Depending on the experimental conditions i.e. high or low temper ature, monomeric or polymeric nature of bonded silica, and nature of t he organic modifier (with low dielectric constant) changes in retentio n pattern were observed. The overall was applied to the separation of triacylglycerols, main components of animal and vegetal oils and fats. The use of optimization criteria leads to determine the best chromato gram It is shown that the optimal conditions are following: a C-18 or C-22 bonded silica percolated with an isocratic mobile phase MeCN/CH2C l2 68/32 such as the stationary phase adopts a polymeric behavior. Abo ut fifty oils and fats from different biological origins have been ana lyzed and comparative fingerprints are established.