DETERMINATION OF FAT-SOLUBLE VITAMINS BY LIQUID-CHROMATOGRAPHY IN PEDIATRIC PARENTERAL NUTRITIONS

A reversed phase high performance liquid chromatographic method using narrow-bore columns packed with 3 mu m particles is described for the simultaneous determination of transretinol, ergocalciferol, DL-alpha-tocopherol and phytomenadione. The fat-soluble vitamins were separated in a C-18, bonded phase column and eluted with methanal as the eluent pumped at a flow rate of 0.2 mL/min. A spectral detector was used and the wavelenghts were set at 325, 265, 284 and 250 nm far vitamin A, D-2, E and K-1 respectively. All vitamins were separated in less than 13 minutes This method was applied to the determination of fat-soluble vitamins in the pediatric parenteral nutritions. The effect of the nutrition composition, daylight and the plastic infusion tubing on the stability of the vitamins was studied. Recovery studies showed good results for all solutes (91.0% - 110.5%) and the coefficients of variation were always less than 3%.