Product Description

Grams Staining Kit is supplied by Micromaster. This kit contains a 125ml bottle of Gram’s Crystal Violet, Gram’s Decolourizer (2 bottles), Gram’s Iodine and Safranin (0.5% v/w). It is advisable to store this kit between 10- 30°C in tightly closed container and away from bright light. After opening, the product should be properly stored in a dry ventilated area protected from extremes of temperature and sources of ignition.

• Quantity provided: 5 x125ml/Bottle

The Gram stain is a differential staining technique most widely applied in all microbiology disciplines laboratories. It is one of the most important criteria in any identification scheme for all types of bacterial isolates. Different mechanisms have been proposed to explain the gram reaction. There are many physiological differences between gram-positive and gram-negative cell walls. Ever since Christian Gram has discovered Gram staining, this process has been extensively investigated and redefined. In practice, a thin smear of bacterial cells is stained with crystal violet, then treated with iodine-containing mordant to increase the binding of primary stain. A decolorizing solution of alcohol or acetone is used to remove the crystal violet from cells that bind it weakly and then the counterstain (like safranin) is used to provide color contrast in those cells that are decolorized. Gram-positive bacteria have a thick mesh-like cell wall made of peptidoglycan (50–90% of cell envelope), and as a result are stained purple by crystal violet, whereas gram-negative bacteria have a thinner layer (10% of cell envelope), so do not retain the purple stain and are counter-stained pink by safranin. In a properly stained smear by gram staining procedure, the gram-positive bacteria appear blue to purple and gram negative cells appear pink to red.