It is said that L-carnitine is effective for fat burning and for dieting, acetyl-L-carnitine is effective for brain aging prevention and for reducing fatigue. Acetyl-L-carnitine is a metabolite of L-carnitine. Both compounds are used as components of supplements, etc.

In this technical note, we introduce a HPLC method to measure L-carnitine and acetyl-L-carnitine with UV detector and reversed phase column. L-carnitine is very hydrophilic compounds, though it was retained on ODS column with ion-pair reagent and separated from impurities in an energy drink and a supplement.