محلول ذخیره رنگ متضاد هوکر

Hucker’s Counter Stain (Stock Solution) is a secondary stain used in the Gram staining procedure to provide contrast by staining Gram-negative bacteria pink or red after the primary stain and decolorization steps.

🏭⚗️ Production
This stock solution is typically prepared by dissolving safranin dye in distilled water or ethanol to a specific concentration, commonly around 0.25% w/v. The solution is mixed thoroughly until the dye is completely dissolved, then filtered to remove any particulates. It is stored in a dark container at room temperature to maintain stability and prevent photodegradation.

🔬 Properties
Hucker’s counter stain is a red or pink-colored, water-soluble basic dye that binds to the thinner peptidoglycan layer in Gram-negative bacterial cell walls. It provides a contrasting color to the crystal violet-stained Gram-positive cells, enabling clear differentiation under a microscope.

🧪 Applications
This counter stain is applied during the final step of the Gram staining process. It stains decolorized Gram-negative bacteria, allowing microbiologists to distinguish them from Gram-positive bacteria. It is widely used in clinical, environmental, and research microbiology laboratories.

⚠️ Safety
Handle with care; safranin may cause skin and eye irritation. Use gloves and eye protection, work in a well-ventilated area, and avoid ingestion or inhalation. Dispose of waste in accordance with local chemical safety regulations.