EDTA Buffer, pH 8 1 mM Working Solution

5 Tris/EDTA/Tween Buffer, pH 9 (10 x Stock Solution) 

EDTA and Tris/EDTA-based high pH buffers are useful for antibodies with low expression levels or when the tissue is over-fixed, but the tissue sections suffer under the high pH conditions and a non-specific background appears. EDTA or Tris/EDTA-based buffers are also commercially available under different names such as Target Retrieval Solution, pH 9 (Dako). Different observations reported non-specific nuclear staining using retrieval solutions containing Tris buffer, the addition of urea could solve this problem. 

---