Summary of ELISA protocol pipetting and washing techniques

Mondo Science Updated on 2024-02-22

The accuracy of ELISA immunoassays is characterized by reproducibility between wells (within assays) in a single experiment and between multiple experiments (inter-assay). A high CV value indicates low accuracy and is usually caused by two reasons: pipetting technique and washing technique.

Pipetting technique:

1.When pipetting, the tip should be aligned with the well** and avoid touching the wall and bottom of the well.

2.Mix the reagent with gentle shaking after pipetting.

3.If your sample is viscous, pre-rinse the tip to remove the effect of surface tension. Wait a few moments for the volume to equilibrate before taking it out.

4.Inadequate pipetting or uneven pipetting volume indicates that the pipette needs to be calibrated. Check the pipette and recalibrate if necessary.

5.When dispensing, make sure to change tips between different reagent standards and samples to avoid cross-contamination.

6.Make sure to use the right tip. An ill-fitting tip does not allow for proper measurement of aspiration and dispensing volumes.

Washing technology:

1.If using an automated microplate washer or multichannel pipette, make sure the inlet and outlet are functioning properly.

2.After the last wash, invert the plate to pour out the excess wash solution and pat the liquid dry on absorbent paper. Washing the plate too quickly or too slowly will reduce accuracy. Do not allow the liquid in the well to air dry naturally, and the next step should be carried out immediately.

3.According to the instructions, add sufficient amount of washing solution to the wells and ensure that the washing is complete.

4.Since the wash solution is not universal, do not use the wash solution from another kit when the wash solution inside the kit is used up. If needed, you can contact technical support for assistance.

5.Do not reduce or increase the soaking time during washing or skip the soaking step.

6.Wash according to the recommended number of washes on the instructions, and changing the number of washes will affect the accuracy of the experiment.

PCR test kits

Related Pages