I am new to the world of ELISA and I am having some trouble getting my standard curve to work.
I purchased a competitive ELISA kit to measure Salivary Cortisol in humans.
So far I have run 4 trials but none of them have produced readings to match the concentrations of the 6 standards I recieved in the kit.
For example - One of the standards is supposed to contain 3.0 ug/dL however the absorbance readings lead to a calculated concentration of only 2.551 ug/dL
Does anyone know why this would continue to happen? My duplicate wells match almsot perfectly, I centrifuge and vortex my controls and standards as required but continue to get incorrect results...
Any suggestions you could make would be much appreciated.