Gram Stain Advanced™ Kits

Used to stain microorganisms from cultures or specimens by the differential Gram method. Produces Gram stains with brighter more distinct colors.

Features & Benefits:

Create vivid Gram-positives:

• Gram-positive organisms retain their deep blue stain; even those that are easily decolorized, such as Bacillus spp. You don’t need to worry about over-decolorizing

Brighten Gram-negatives:

• Gram-negative organisms will appear brighter with better definition at the edges
• The stained cells are less likely to be over-washed
• Anaerobes, especially Fusobacterium spp. will be a darker red than with conventional stains
• You will also notice a marked improvement with other Gram-negatives, such as Neisseria spp

Differentiate mixed cultures:

• When mixed on a slide, Gram-positives and negatives will be easier to distinguish, due to an overall brighter stain

Save time:

• No mixing or breaking of ampules is required
• All stains are ready-to-use and have a two year shelf life from date of manufacture

Gram Stain Kit Advanced™ Kit includes:

• Hucker's Crystal Violet
• Iodine, stabilized
• Decolorizer, Fast, 75% acetone, 25% alcohol
• Counterstain, Advanced

What Are Gram-Positive Bacilli?

Rod-shaped bacteria called Gram-positive or Gram + bacilli are harmless, but a few are responsible for some of the life-threatening diseases in human history. During a Gram staining process, Gram-positive organisms exhibit a crystal violet stain while Gram-negative ones show a pink or red stain.

Key Characteristics of Bacillus "Gram-Positive"

• A thick peptidoglycan cell wall: Gram-positive bacilli are wrapped in a dense, multi-layered mesh of peptidoglycan, which is a sugar-and-protein lattice that traps the purple stain inside the cell. Gram-negative bacteria have a much thinner version of this wall, plus an extra outer membrane, which is why they wash out and appear pink under the microscope.

• Some of them can go dormant: Bacilli and Clostridia can enter a survival mode called sporulation. The resulting endospore can shrug off boiling water, UV radiation, dehydration, and most household disinfectants, then spring back to life once conditions improve. This is part of why anthrax spores can sit in soil for decades and still be infectious.

• Their oxygen needs vary: There's no single rule here. Some species need oxygen to survive, some are killed by it, and others function either way. 

• Many of them are toxin factories: Many pathogenic species harm humans by pumping out exotoxins, proteins engineered by evolution to disable parts of human cells.

Examples of Gram-Positive Bacteria