23.03.2023 - 00:25

Explain the steps of the staining method for acid-fast stain.

Question:

Explain the steps of the staining method for acid-fast stain.

Answers (1)
  • Eros
    April 9, 2023 в 20:37

    The acid-fast stain is a laboratory technique used to differentiate acid-fast bacteria from non-acid-fast bacteria. This staining method is commonly used to identify mycobacteria, such as Mycobacterium tuberculosis, which are responsible for causing tuberculosis.

    The acid-fast staining method involves several steps as follows:

    1. Preparation of the smear: A thin smear of the bacterial sample is prepared on a clean glass slide and allowed to air dry.

    2. Fixation: The smear is fixed onto the slide by heat fixation, which involves passing the slide through a flame a few \times.

    3. Primary staining: The smear is then covered with a solution of carbolfuchsin, a red dye that is lipid-soluble and can penetrate the bacterial cell wall. The slide is heated over a steam bath for several minutes to allow the dye to penetrate the bacterial cells.

    4. Decolorization: After staining, the slide is washed with acid-alcohol, which removes the carbolfuchsin dye from non-acid-fast bacteria but not from acid-fast bacteria.

    5. Counterstaining: The smear is then counterstained with a contrasting dye, usually methylene blue, which stains non-acid-fast bacteria blue, while the acid-fast bacteria remain red.

    6. Microscopic examination: The stained smear is then examined under a microscope for the presence of acid-fast bacteria. Acid-fast bacteria will appear as red, rod-shaped structures, while non-acid-fast bacteria will appear blue.

    In conclusion, the acid-fast staining method involves a series of steps that allow for the differentiation of acid-fast bacteria from non-acid-fast bacteria. The primary stain, carbolfuchsin, penetrates the bacterial cell wall of both acid-fast and non-acid-fast bacteria, but the decolorization step removes the dye from non-acid-fast bacteria. The counterstain, methylene blue, is used to stain the non-acid-fast bacteria, making them visible under the microscope. Acid-fast bacteria remain red after the counterstain, allowing for their identification.

Do you know the answer?
Not sure about the answer?
Find the right answer to the question Explain the steps of the staining method for acid-fast stain. by subject Bacteria, and if there is no answer or no one has given the right answer, then use the search and try to find the answer among similar questions.
Search for other answers
Authorization
*
*

Password generation