| Abstract [eng] |
The most effective way to simplify gas chromatographic analysis of fatty acid isomers is to fractionate the sample through a sorbent capable of separating cis and trans isomers of unsaturated acids. Therefore, the aim of this work is to develop and study silver ion and silver nanoparticle modified solid phase extraction sorbents in order to adapt them for the fractionation of geometric isomers of fatty acid methyl esters. Using a silica gel as a sorbent, silver ion solid phase extraction system has been developed and optimized for the separation of trans fatty acids in human adipose tissue. The results obtained were compared with those obtained using a commercial column. The main drowback of silver ion-based sorbents is the instability of ionic silver, which limits their reusability. Silver nanoparticle-modified monolithic sorbents have recently become a promising class of materials, and the operating principles of such sorbents are similar to those of silver ion-based sorbents. Conditions for synthesis of silver nanoparticles were successfully investigated and optimized for their formation in laboratory synthesized and amino propyl groups modified silica gel monoliths, which have a particularly large surface area (442 m2 g-1) and pore volume (0.9 cm3 g-1). The silver nanoparticle modified solid phase extraction system works as efficiently as the ionic silver systems for separation of trans fatty acids, but has excellent stability and can be used for multiple fractionations. |
