Melatonin is an indoleamine hormone synthesized by the pineal gland that entrains circadian rhythms and acts as a direct free-radical scavenger, supporting research in chronobiology, sleep science and oxidative biology. Its dual receptor-mediated and antioxidant actions make it a versatile research compound. The product is supplied as a white lyophilized powder at >=99% HPLC purity in a sealed vial. Complete documentation and flexible ordering are provided. Our quality assurance process includes raw material screening, synthesis monitoring and final HPLC analysis, with results documented for each lot. Buyers can request batch-specific information before ordering, and our technical staff can advise on reconstitution, storage and handling for each peptide.