Microchemical Journal, cilt.205, 2024 (SCI-Expanded)
Melatonin, recognized as the hormone governing sleep, is an endogenous hormone synthesized by the pineal gland situated in the brain. It orchestrates the sleep-wake cycle and fosters optimal circadian rhythm. Owing to its manifold metabolic advantages, particularly in the realm of circadian rhythm regulation, melatonin finds extensive application in various supplementary formulations. The elimination of hazardous chemical waste in common chromatographic separations has become an essential issue. We present a green, eco-friendly, novel, sensitive, rapid, robust, and three simple methods including the HPLC-PDA, HPLC-FLD, and HPLC-ELSD approach for the simultaneous determination of MEL in various products. The mobile phase of all the HPLC methods consists of only water and an ethanol mixture and is free from any toxic solvents. All the separations were made on a C18 column (5 μm particle size, 250 mm x 4.6 mm id.). LODs were found to be as 1.20 ng mL−1, 0.02 ng mL−1, 1.26 µg mL−1, and LOQs 4.00 ng mL−1, 0.07 ng mL−1, 4.21 µg mL−1 for PDA, FLD and ELSD, respectively. The recovery results were found to be within 98.58–102.35 %. Moreover, the greenness assessment of all the HPLC methods was assessed using the Analytical Eco-scale, NEMI, AGREE, and GAPI. The developed methods have been demonstrated to be applicable in routine analyses for the determination of melatonin in various preparations.