Reagents

1. Sodium Borohydride (NaBH₄) - 1 mg/ml
2. Carbonate:Bicarbonate Buffer, pH 9.6
3. Sodium Periodate (NaIO₄) - 1 mM, 2.14 mg/10 ml Acetate Buffer
4. 10mM Acetate Buffer, pH 4.5
   0.82 g sodium acetate in 90 ml diH₂O. 
   Adjust to pH 4.5 with glacial acetic acid.  Q.S. to 100 ml with diH₂O.

 Procedure

1. To one-half the plate add 100 ml/well periodate.  To the other half add 100 ml/well acetate buffer.
2.  Incubate 2 hr at 37^oC.
3. Wash 2X with 0.1M bicarbonate buffer.
4.  Add 100 ml/well sodium borohydride.
5. Incubate 30 min, RT
6. Wash plate 2X with PBS
7. Block plate as required by assay protocol.

 Notes

In fixed cell ELISAs. do not use carbonate wash before substrate