Hello Deni Pepy

You may initially try using the undiluted normal serum/plasma samples for the ELISA assay. If your samples do not fall within the linear range of the standard curve for accurate measurement, you will have to dilute your samples. However, the optimal dilution can vary depending on the concentration of the analyte. So, it would be difficult to mention the sample dilution for each of these biomarkers. You will have to try a few dilutions to ensure the diluted sample falls within the linear range of the standard curve.

If you need to dilute your samples, you may want to refer to the following.

For 100-fold dilution: One-step dilution. Add 5μL sample to 495μL sample diluent to yield 100-fold dilution.

For 1000-fold dilution: Two-step dilution. Add 5μL sample to 95μL sample diluent to yield 20-fold dilution, then add 5μL of 20-fold diluted sample to 245μL sample diluent, resulting in the neat sample being diluted at 1000-fold dilution.

Best,