Gram Stains Kit

Gram stain is one of the most frequently used, first step, processes to identify bacteria – used daily in hospitals. It quickly and cost effectively divides bacteria into one of two types: Gram positive or Gram negative. Once differentiated, further relevant tests help determine the precise bacteria.

The Gram's Stain process is based on Hans Christian Gram's discovery that bacteria are divided into two groups: those that retain a stain (Gram positive) and those that do not (Gram negative). This process involves staining a sample of bacteria on a slide with Hucker's Crystal Violet and then fixing it with iodine solution.

Solvent (acetone-alcohol) is then applied in order to wash out (de-colorize) the Crystal Violet from Gram negative cells. The Gram positive cells will retain the Crystal Violet stain. After quickly rinsing in water, Safranin O is applied to the sample in order to re-colorize the Gram negative cells; this final step in order to provide greater contrast in the Gram negative cells and make them easier to see.