I'm having problems on fitting a standard curve of ELISA Kit from Crystal Chem. On data sheet, it's said to do a 4PL standard curve and I did that on GraphPad Prism, obtained all the values to put on the equation given by the software manual ( Y=Bottom + (Top-Bottom)/(1+10^((LogEC50-X)*HillSlope) but it's not working. When I put the absorbance values at Y to obtain the concentration at X, I don't obtain the value given by the kit, as expected for the controls.
Can someone help me?? Please!! I'm trying to do that for 3 days!!