Possible cause and recommended solutions:
- Pipetting errors in preparation of standards > Avoid pipetting small volumes (<5 µL) and be careful not to splash from well to well
- Air bubbles formed in well(s) > Use reverse pipetting technique
- Standard stock is at incorrect concentration > Always refer to dilutions described in Assay preparation
- Improperly thawed reagents > Thaw all components completely and mix well before use
- Use of improperly stored reagents > Store the components appropriately and use fresh components from the standard curve
- Incorrect incubation times or temperatures > Refer to Assay protocol