Monosan Peroxid-Block

Intended use: The blocking solution Peroxide Block is intended for inhibition of endogenous peroxidase activity in tissue sections. It is primarily intended to be used in immunohistochemistry on formalin-fixed paraffin-embedded samples if using a detection system with horse radish peroxidase.

Summary and explanation: Endogenous peroxidase activity in the tissue can result in unspecific background staining in immunohistochemical staining procedures using horse radish peroxidase (HRP) as detection enzyme. This effect can be eliminated when tissue sections are incubated with Peroxide Block prior to immunohistochemical staining. Hydrogen peroxide in the solution blocks the activity of endogenous peroxidase.

Reagents provided: 500 ml Peroxide Block (ready-to-use)

Storage and handling: The solution should be stored at 2-8°C without furt her dilution. Please store the reagent in a dark place and do not freeze it. Avoid exposure to strong light. Under these conditions the solution is stable up to the expiry date indicated on the label. Do not use product after the expiry date. A positive and a negative control have to be carried out in parallel to the test material. If you observe unusual staining or other deviations from the expected results which could possibly be caused by this reagent, please contact our technical support.

Principle of method: Peroxide Block is applied onto tissue sections to reduce non-specific staining due to endogenous peroxidase activity in immunohistochemistry. The step is carried out before incubation with primary antibody but after dewaxing and rehydration. If a heat induced epitope retrieval (HIER) or enzymatic digestion is necessary for immunohistochemical detection it is of no importance if the Peroxide Block is used before or after this step. In some cases it has been shown, that blocking of endogenous peroxidase before the epitope retrieval leads to better results.

Procedure: 1. Apply Peroxide Block for 10 minutes at room temperature. The section should be covered completely. 2. Rinse with wash buffer. 3. Proceed with next steps for immunohistochemical staining as usual starting with protein blocking or the primary antibody.

Expected results: During the reaction of the substrate with horse radish peroxidase or alkaline phosphatase in the presence of a chromogen, a coloured precipitate is formed at the location of the bound primary antibody. This reaction only takes place if the target antigen is existent in the tissue. The chromogen used determines the colour of the precipitate. The analysis is carried out using a light microscope

References: Elias JM Immunohistopathology – A practical Approach to Diagnosis ASCP Press 2003/Nadji M and Morales AR Ann N.Y. Acad Sci 420:134-139, 1983

• Artikelnummer: SANMON-APP147
• Hersteller: Sanbio / Monosan
• Hersteller Artikelnummer: MON-APP147
• Verpackungseinheit: 500 ml
• Mengeneinheit: STK
• Methode: Immunofluorescence, Immunohistochemistry (frozen), Immunohistochemistry (paraffin)