Acid Fast Stain (Phenol-free fuchsin staining method for auto stainer) Baso Clear Colourful Stains

Testing Principle

Acid-fast bacteria, such as Mycobacterium (e.g., Mycobacterium tuberculosis), have a lipid or wax-like membrane on their surface, making them difficult to stain. However, once stained, they resist decolorization even when treated with acid-alcohol. This characteristic is utilized by first staining with an enhanced staining solution, then treating with acid-alcohol to decolorize non-acid-fast bacteria, followed by a counterstain. As a result, acid-fast bacteria retain the initial stain color (red), making them easy to identify.

This product improves upon the traditional Ziehl-Neelsen acid-fast staining method by modifying the carbol fuchsin solution to exclude phenol (also known as carbolic acid) while still allowing acid-fast bacteria to stain a vivid red. The counterstain uses methylene blue, creating a sharp contrast between the color of the acid-fast bacteria (red) and the background (blue).

Stain Results
Against a light blue background, acid-fast bacteria (e.g., Mycobacterium tuberculosis) appear red, while other bacteria and cells appear blue.

Acid-fast bacteria (using Mycobacterium tuberculosis as an example):Most are rod-shaped and slightly curved.The width of the bacteria ranges from 0.3~0.6 μm.The length varies between 0.5~8 μm, with most falling within 1.5~3.5 μm.A few longer bacteria may appear spiral-shaped.In well-stained Mycobacterium tuberculosis, deeply stained metachromatic granules can be observed within the bacterial cells.In fresh specimens containing a high concentration of Mycobacterium tuberculosis, after acid-fast staining and observation under a 100× oil immersion lens, individual bacteria can be seen, as well as clusters or branching arrangements of bacteria.

Packaging Specification