Human Melatonin ELISA Kit

This competitive ELISA kit from Assay Genie enables quantitative measurement of melatonin in human samples. The microtiter plate is pre-coated with melatonin antigen in a competitive format, where melatonin in the sample competes with the immobilised antigen for binding sites on a biotinylated detection antibody. After washing, HRP-Streptavidin and TMB substrate are added; absorbance is read at 450 nm, with colour intensity inversely proportional to melatonin concentration.

Suitable sample types include serum, plasma, cell culture supernatant, cell or tissue lysate, and other liquid samples. The kit reports a sensitivity of 4.688 pg/mL and a measurable range of 7.813-500 pg/mL. Linearity (n=10) across 1:2, 1:4, and 1:8 dilutions is reported for serum (86-103%, 89-98%, 81-97%), EDTA plasma (91-98%, 82-97%, 82-97%), and heparin plasma (89-103%, 84-99%, 83-93%). Reported recovery ranges are 85-99% for serum (average 91%), 87-94% for EDTA plasma (average 92%), and 87-105% for heparin plasma (average 94%).

The protocol includes a 30-minute TMB substrate equilibration, addition of 50 µL standard or sample with 50 µL biotin-labelled antibody per well, incubation at 37°C for 45 minutes, washing, colour development in the dark at 37°C for 10-20 minutes, stop solution addition, and absorbance measurement at 450 nm. Components are stored sealed at 2-8°C with cryopreservation not recommended; the kit is shipped on ice packs and the box label lists the expiry date. A Bradford Reagent is included for total protein quantification.