Normally people draw ELISA standard curve by using specialized tools for curve fitting, such as: Curve Expert 1.3
Below is "Curve Exert1.3" software, for example, draw the ELISA standard curve as follows:
1. Start "Curve Expert1.3" (Curve Expert1.3 free download. Zip)
2. X-axis: input the OD values of standard, Y-axis: input values corresponding to the concentration, as shown:
3.Click [Run] button, the following dialog box appears
4 Click [ok] button, the following two dialog boxes appear, then close the dialog box below
5. A list of some curves appears at the upper right corner of the dialog box, from "1" Start to click the name of curves, then the corresponding fitting curve will appear in the lower right corner.
6. Double click the best fitting curve for ELISA test, the dialog box appears as follows:
Note: select curve equation with the best coefficient (the "r" value) for computing. In the following dialog box, the "r" value at the upper right corner (close to 1 means the better fitting)
7. Press [Ctrl] key + [L] key, the following dialog box appears:
8. Enter the standard OD values, click [Calculate] button, you can get the actual content of the target protein. (N-fold diluted samples, calculate the value should be multiplied by N).
9. If you would like to have the curve fitting equation of ELISA, right-click blank space of the dialog box in step 6, choose "Information"
10.Get the following dialog box: Click "Copy"
You can paste in the location you want to obtain the data as follows:
3rd degree Polynomial Fit: y=a+bx+cx^2+dx^3...
a = -0.0010925264
b = 0.11260362
c = 0.00071609266
d = -4.6172104e-005