Simultaneous determination of melatonin and pyridoxine in tablets by gas chromatography-mass spectrometry

A gas chroma tographic-mass spectrometric (GC-MS) method for the qualitative and quantitative determination of melatonin plus pyridoxine commercial tablets is described. Melatonin and pyridoxine were simultaneously determined by GC-MS after extraction from ground tablets with methanol and derivatization with N-methyl-N-N-trimethlyisilyltrifluoroacetamide (MSTFA). The mass chromatograms were generated using 232 m/z ion for melatonin and 280 m/z ion for pyridoxine, respectively. Splitless injection offers good reproducibility with a standard deviation of 2%. The developed method was applied to analyze the melatonin and pyridoxine content from two different tablet formulations. Also, recovery, detection and quantification limits are reported