Stain reagent kit BA4090

for microbiologyMycobacterium tuberculosis

This kit is based on the Ziehl-Neelsen method recommended by the WHO and it is a chemistry stain intended for the detection of acid-fast bacteria such as Mycobacterium tuberculosis. Principle: Acid-fast bacteria such as Mycobacterium tuberculosis and Mycobacterium leprae are difficult to stain because of their lipoid capsule in the cell wall. However, once the lipoid capsule is stained with an enhanced dye such as carbolfuchsin, the newly formed compound will resist decolorization from acid-alcohol and retain the original color stained (red), which can be easily differentiated from other microorganisms that still adsorb the counter blue stain. Phenol is mordant and is able to improve the staining ability. Methods: 1. Deparaffin tissue, add Carbolfuchsin, heat with small flame and keep the stain steaming for 5~10 minutes. Avoid vaporizing to dry or boiling. 2. After cooling, rinse with water gently. Blot up the slide gently with bibulous paper. 3. Decolorize for 1~2 minutes with Acid Alcohol. 4. Rinse with water gently (if red is still visible on the surface of specimen, add Acid Alcohol again until red is completely decolorized. Then continue rinsing with water). 5. Apply Methylene Blue for 20~30 seconds. Rinse with water gently. 6. Differentiate in 95% ethanol for 5~10 seconds. 7. Dehydrate in absolute ethanol and clear with xylene. Mount with mounting media. 8. Alternatively, the dehydration step shown above can be replaced by air drying. 9. Examine the finished slide under an oil immersion lens.