Used for the quantitative measurement of Melatonin Sulfate in human urine, plasma, and serum samples. This ELISA kit is widely applied in clinical research and biomedical studies to assess melatonin metabolism, circadian rhythm disorders, sleep-related conditions, and neuroendocrine function. It enables high-throughput analysis with high sensitivity and specificity, making it suitable for epidemiological studies and pharmacological research involving melatonin pathways. The assay supports investigation into sleep quality, shift work effects, jet lag, and neurological or psychiatric disorders linked to melatonin dysregulation.