Gram staining how does it work

The length of decolorization is a critical step in gram staining as prolonged exposure to a decolorizing agent can remove all the stains from both types of bacteria. The final step in gram staining is to use basic fuchsin stain to give decolorized gram-negative bacteria pink color for easier identification. It is also known as counterstain. Some laboratories use safranin as a counterstain; however, basic fuchsin stains gram-negative organisms more intensely than safranin.

Similarly, Hemophilus spp. Excerpt The Gram staining is one of the most crucial staining techniques in microbiology. The process involves three steps:. Your Account. Gram Staining Created by Monica Z. Bruckner What is Gram Staining?

But if i may ask, which step in Gram staining tech can be omited without affecting the final result? Mr Len artifacts results from poor methods of rinsing of slides. Beside, what is the color of safranin? More of a controlled decolorization. If Gram positive organisms have such complex cell wall that could defy decolorisation,why then is a mordant used?

Moreover, the test procedure is performed to differentiate between the two groups of bacteria. Save my name and email in this browser for the next time I comment.

Principle of Gram Staining When the bacteria is stained with primary stain Crystal Violet and fixed by the mordant, some of the bacteria are able to retain the primary stain and some are decolorized by alcohol.

Prepare the smear of suspension on the clean slide with a loopful of sample. Air dry and heat fix Crystal Violet was poured and kept for about 30 seconds to 1 minutes and rinse with water. Add safranin for about 1 minute and wash with water. Air dry, Blot dry and Observe under Microscope. Purple colour Reply.