DAB (DIAMINOBENZIDINE)

DAB is prepared by dissolving the contents of 1 g bottle of DAB in 25 ml dH2O and filtering with a disposable unit attached to a disposable syringe. Aliquots containing 1 mg DAB per 25 µl of solution are stored in 1.5 ml microfuge tubes in a -20°C freezer. Thawed aliquots may be refrozen. To minimize risk in handling this carcinogen, use disposable plastic containers and pipettes wherever possible. Treat waste with bleach.

DAB HEAVY METAL STAIN

Presoak solution
4 mg DAB
5 ml 0.6% Ni(NH4)2(SO4)2
5 ml 0.2 M Tris buffer, pH 7.4
50 μl DMSO

After presoak interval, add:
10 μl 3% H2O2

Final concentrations are 0.04% DAB, 0.1 M Tris buffer, 0.3% Ni(NH4)2(SO4)2 and 0.003% H2O2.

DAB PRESOAK SOLUTION

25 µl (=1 mg) DAB stock solution
1 ml 0.1 M PO4 Buffer, pH7.3
1 ml dH2O
20 µl DMSO

After presoak interval, add:
5 µl 3% H2O2

Final concentrations are 0.05% DAB, 0.05 M PO4, 1% DMSO and 0.004% H2O2.

DAB SOLUTION

0.05% diaminobenzidine, 1% dimethyl sulfoxide in 0.05 M PO4 buffer, pH 7.3.