HPLC analysis of S-adenosyl-L-methionine in pharmaceutical formulations.

A validated analytical method of S-adenosyl-L-methionine (SAM) in pharmaceutical preparations by reversed phase high performance liquid chromatography (RP-HPLC) is described. The compound is separated by a 2.1 mm x 15 cm, 5 microns--Discovery C18 column with isocratic elution. The effect of different anionic surface active agents with different molarity on the separation was studied. A direct relationship between the molarity of the surface active agents and the capacity factor (k') was found. The limit of detection was 0.49 mmol/ml and the linearity was r = 0.999 in the concentration range 20-100 micrograms/ml. Inter- and intra-assay variation was determined for three selected concentrations (20, 60, 100 micrograms/ml) by calculating the analytical recoveries with a range of 97.0-99.9%. The procedure was also suitable to check the stability of S-adenosyl-L-methionine in solution at room temperature.