The Direct Saliva Melatonin RIA kit measures melatonin by a double-antibody radio immunoassay based on the Kennaway G280 anti-melatonin antibody.
Human saliva samples and reconstituted standards and controls are incubated with the anti-melatonin antibody and 125I-melatonin.
125I-melatonin competes with melatonin present in samples, standards and controls.
After 20 hours of incubation, solid-phase second antibody is added to the mixture in order to precipitate the antibody-bound fraction.
After aspiration of the unbound fraction, the antibody bound fraction of 125I-melatonin is counted