Before performing quantitative ELISA, you need a standard curve that performs well. This ensures you can reliably determine the concentration of your samples.
Note: If using one of our ELISA kits, the measurement values can vary considerably from the examples shown on the datasheet or protocol booklet. This is usually to be expected, so long as the curve has a good fit, as measured by the regression coefficient (R2). As long as the R2 0.9, the standard curve can be used with confidence.
Standard may be degraded.
Store and handle the standard as recommended.
Pipetting error.
Use calibrated pipettes and proper pipetting technique.
The standard solution has not been diluted correctly.
Confirm dilutions are made correctly.
The standard has been improperly reconstituted.
Briefly spin the vial before opening; inspect for undissolved material after reconstituting.
Curve-fitting model doesn't work
You may need a different curve-fitting model.
You should always follow the manufacturer's instructions in the first instance. However, if the curve-fit doesn't seem to work, try plotting using different models.