Application of a validated HPLC-PDA method for the determination of melatonin content and its release from poly(lactic acid) nanoparticles.

Melatonin is a natural hormone and with the advancement of age its production declines and thereby may result in some neurological disorders. Exogenous administration of melatonin has been suggested as a neuroprotective agent. Due to its low oral bioavailability, the loading of melatonin in polymeric nanoparticles could be an important tool to effectively use exogenous melatonin.

PLGA Nanoparticles and Polysorbate-80-Coated PLGA Nanoparticles Increase the In vitro Antioxidant Activity of Melatonin.

Background: Melatonin is an endogen substance with several physiological functions, acting as an important antioxidant. Our objective was to prepare nanoparticles composed of poly(lactic-coglycolic acid) (PLGA) coated with polysorbate 80 (PLGA-PS80) or uncoated (PLGA) nanoparticles containing melatonin (MLT) and evaluate their in vitro cytotoxicity over erythrocytes and in vitro antioxidant activity.

Methods: Nanoparticles were obtained by an emulsion-solvent evaporation method and characterized by size, morphology, polydispersity index, zeta potential, encapsulation efficiency, thermal properties and in vitro drug release profile.