Determination of Melatonin in Commercially Available Products by LCEC and LC/MS/MS

Abstract
Simple and reliable methods for liquid chromatography/electrochemistry (LCEC) and LC/MS/MS with atmospheric pressure chemical ionization (APCI) have been developed for the determination of melatonin in commercially available products. The dissolution of melatonin from the melatonin-containing formulations was simply obtained by dissolving the tablets and capsules in 20% acetonitrile in 0.1 N perchloric acid with ultrasonication. The filtrate of the resultant solution was separated on a 1 × 150 mm C