Procedure
1. Block sample as usual with a protein-based blocker (e.g., normal serum or Blocker™ BSA in TBS, Product No. 37520).
2. Cover sample with 0.1 mg/ml (~1.7 µM) streptavidin diluted in Wash Buffer; incubate 15 minutes at room temperature.
3. Wash three times for 10 minutes each with Wash Buffer.
4. Add 0.5 mg/ml (~2 mM) Biotin dissolved in Wash Buffer; incubate for 30-60 minutes at room temperature.
5. Wash three times for 10 minutes each with Wash Buffer.
6. Continue with usual assay procedure by adding biotin-labeled probe (e.g., biotinylated antibody).