Acid-Fast Bacillus (AFB) stain kit (ziehl-neelsen's method)

The cell walls of acid-fast bacteria (mycobacteria, tuberculosis bacteria, Nocardia, etc.) contain a large amount of lipids surrounding the outside of peptidoglycan, so acid-fast bacteria do not stain or stain lightly in general bacterial staining solutions. Traditional staining methods require heating and prolonged staining time to promote staining. Once the mycolic acid in the cell wall of acid-fast bacteria combines with the dye, it is difficult to be decolorized by acidic decolorizing solutions, hence the name acid-fast staining.

Acid-fast stain kit (ziehl-neelsen method) belongs to the acid-fast bacteria hot staining method, which is fast and easy to operate. The principle of staining is that under heating conditions, the red staining solution can better penetrate the cell wall of acid-fast bacteria to color. After counterstaining with methylene blue, the acid-fast bacteria are still red, while other bacteria and background substances are blue. This staining solution is darker than the Kinyoun cold staining method, and the contrast is clearer.