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Gram Stain Kits and Reagents are used to stain microorganisms from cultures or specimens by the differential Gram method.

The Gram stain was devised in 1884 by Christian Gram in an attempt to differentiate bacterial cells from infected tissue. Although Gram observed what is now called the "Gram reaction," he did not recognize the taxonomic value of his technique.

The Gram stain is now used to differentiate intact, morphologically similar bacteria into two groups based on cell color after staining. In addition, cell form, size and structural details are evident. Such preliminary information provides important clues to the type of organism(s) present and the further techniques required to characterize them.

Because inorganic iodine is rapidly oxidized and loses its effectiveness as a mordant,¹ the Gram Stain Kit (Cat. No. 212539) differs from Gram's original formulation by offering a more stable organic iodine complex, L-polyvinylpyrrolidone-iodine.

Quality control requirements must be performed in accordance with applicable local, state and/or federal regulations or accreditation requirements and your laboratory's standard Quality Control procedures. It is recommended that the user refer to pertinent CLSI (formerly NCCLS) guidance and CLIA regulations for appropriate Quality Control practices.

Run controls using BBL™ Gram Slide (Cat. No. 231401) or 18 - 24 h cultures of known gram-positive and gram-negative microorganisms. The following test strains are recommended:

Approximate Formula* Per Liter

For in vitro Diagnostic Use.

Over time, a fine precipitate may develop in Gram Basic Fuchsin. Product performance will not be affected.

Gram Crystal Violet: Harmful by inhalation and if swallowed. Irritating to eyes, respiratory system and skin. Possible risk of irreversible effects. Keep container tightly closed. Keep away from sources of ignition - No Smoking. Do not breathe gas / fumes / vapor / spray. Wear suitable protective clothing and gloves.

Gram Iodine 100X: Harmful by inhalation, in contact with skin and if swallowed. Keep container tightly closed. Do not breathe gas / fumes / vapor / spray. Avoid contact with skin and eyes. Wear suitable protective clothing.

Stabilized Gram Iodine: Harmful in contact with skin. Causes burns. Irritating to eyes, respiratory system and skin. Keep container tightly closed. Do not breathe gas / fumes / vapor / spray. Avoid contact with skin and eyes. Wear suitable protective clothing.

Gram Decolorizer: Irritating to eyes, respiratory system and skin. Keep container tightly closed and in a well ventilated place. Keep away from sources of ignition - No smoking. Do not breathe gas / fumes / vapor / spray. Avoid contact with skin and eyes.

Gram Safranin: Harmful by inhalation and if swallowed. Irritating to eyes, respiratory system and skin. Keep container tightly closed. Keep away from sources of ignition - No Smoking. Wear suitable protective clothing and gloves.

Gram Basic Fuchsin: May cause cancer. May cause heritable genetic damage. Irritating to eyes. Keep container tightly closed. Do not breathe dust. Avoid contact with skin and eyes. Wear suitable protective clothing.

In case of contact with eyes, rinse immediately with plenty of water and seek medical advice.

Gram Iodine 100X: Immediately remove all contaminated clothing.

After contact with skin, wash immediately with plenty of water.

If inhaled, remove to fresh air. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Seek medical advice.

If swallowed seek medical advice immediately and show the container or label.