SIMULTANEOUS DETERMINATION OF BETAINE AND N,N-DIMETHYLGLYCINE IN URINE

A method is described for the determination of betaine and its metabol ite N,N-dimethylglycine in human urine. The method involves a deaminat ion step and a solid-phase extraction to isolate both substances from urine followed by high performance liquid chromatography (HPLC) separa tion on a 5-mu m SCX column with UV absorbance detection. Limit of det ection is about 0.9 mu g for both substances, Recoveries were > 85%. T he method appears to be suitable for monitoring betaine and its metabo lite in urine of patients undergoing therapy with betaine.