DAB substrate kit for detection of peroxidase (HRP) activity on immunoblots, immunohisto- and cytochemical slides and during in situ hybridization.
ROTI®DAB Kit contains substrate, buffer solution and activation reagent, therefore including all three solutions necessary for HRP detection reaction. Application is very simple - all three kit solutions are diluted equally in water, and the blotting filter membrane, or the slides, are then incubated in this substrate solution. Since the solutions are delivered in drop dispensers, dosing is most convenient.
DAB is oxidized by HRP, forming a brown precipitate, which is insoluble in aqueous and organic solvents. This precipitate can be detected in visible light and does not bleach during long-term storage.
Addition of the DAB Metal Enhancer (Art. No. 9204) doubles the signal strength. Slides may be permanently mounted in hydrophilic, or, after dehydration, in hydrophobic mounting medium.
DAB solution (Art. No. 9869), DAB buffer (Art. No. 9870), and Activation reagent (Art. No. 9871) in dropper bottles. Contents of this Kit may not be bought separately.
Toepassing | Western, in situ, Histochemistry |
Enzyme | Horseradish Peroxidase |
Bewijs | Colour (brown) |
Signaalproduct | Precipitate (Blot) |
Stock solutions (All solutions are stable for at least 1 year at 4 °C):
0.5 g NBT in 10 ml 70 % dimethylformamide;
0.5 g BCIP (p-toluidine salt) in 10 ml 100 % dimethylformamide.
Incubation buffer for alkaline phosphatase:
100 mM NaCl, 5 mM MgCl2,100 mM Tris (pH 9.5).
Fresh substrate solution: 66 μl NBT stock solution + 10 ml incubation buffer, mix well, add 33 μl BCIP stock solution. Use within 1 hour.
Blot development: Approx. 10 ml substrate solution per 15 x 15 cm2 membrane surface. Develop at room temperature until bands become visible (approx. 30 mins).
Reaction stop: Rinse with PBS/20 mM EDTA.
Dissolve 1 mg TMB in 0.1 ml dimethylsulfoxide (Art. No. 4720); add 9.9 ml of a 0.1 M sodium acetate solution (pH 6.0) (Powder: Art. No. 6779), filter and add H2O2 (Art. No. 8070) (final concentration 0.01 %).
Always prepare freshly!
Incubation 10-30 mins at room temperature (approx. 50 μl per microtitre well; finally add 50 μl 1 M H2SO4, Art. No. X873, per well).
Photometric quantitation at 450 nm.
Reference: Bos E.S. et al. (1981) J. Immunoassay 2, (3/4), 187.
Application test (Blotting) | complies |
RNAse | ≤1 ppb |
DNAse | ≤1 ppm |