Quantification of carnitine esters by high-performance liquid chromatography. Effect of feeding medium-chain triglycerides on the plasma carnitine ester profile.

A high-performance liquid chromatographic (HPLC) technique was developed using commercially available derivatization reagents and commonly used reversed-phase HPLC column chemistry to analyze plasma samples for their carnitine ester content. The method proved to be sufficiently sensitive to determine changes in the carnitine ester profile in plasma resulting from metabolic disorders or metabolic insults. The method was tested using plasma samples obtained from pigs fed medium-chain triglycerides (MCT) of different chain lengths (four to seven carbons). The MCT feeding was associated with transient increases in plasma carnitine and carnitine esters, and feeding odd-chain MCT (tri-C5 or tri-C7) led to elevated levels of propionylcarnitine in plasma.