A simple strategy for d/l-carnitine analysis in food samples using ion mobility spectrometry and theoretical calculations

•A simple method for simultaneous recognition of d/l-Carn was investigated.•d/l-Carn were mobility separated by their ternary diastereomeric complex by adding Nat and meal ions.•Metal ions in group IA (Li+, Na+, K+, Rb+, Cs+) have separation effects.•Theoretical calculations were performed to elucidate the enantiomeric separation at the molecular level.•The proposed method was applied to l/d-Carn detection in beverage samples and fresh pork.