Key Features
- Designed for antibiotic potency determination
- Suitable for Amphotericin B and Nystatin assays
- Yeast-based agar diffusion method
- Referenced to USP guidelines
- Dehydrated powder for easy preparation and storage
- Consistent and reproducible laboratory performance
Applications
- Amphotericin B potency testing
- Nystatin potency testing
- Microbiological antibiotic assays
- Quality control analysis
✅ Product Specifications
- Product Name: Antibiotic Medium No. 12
- Alternative Name: Nystatin Assay Agar
- Form: Dehydrated powder
- Package Size: 250 g / bottle
- Storage Condition: Room temperature
- Shelf Life: 3 years
- Reference Standard: USP
- Final pH (25°C): 6.1 ± 0.2
✅ Composition (per liter)
| Component | Quantity |
|---|---|
| Peptone | 10.0 g |
| Beef Extract | 2.5 g |
| Sodium Chloride | 10.0 g |
| Yeast Extract | 5.0 g |
| Dextrose | 2.5 g |
| Agar | 25.0 g |
| Polysorbate 80 | 10 mL |
✅ Preparation Instructions
- Suspend 62.5 g of the product in 1,000 mL of deionized water.
- Heat with stirring until completely dissolved.
- Sterilize at 121°C for 15 minutes.
- Cool to 45–50°C and pour into sterile Petri dishes.
- Allow to solidify before use.
✅ Test Method (Optional Technical Section)
- Inoculate the test microorganism into sterile agar cooled to 40–45°C.
- Overlay evenly onto the surface of the base agar.
- Allow 10–20 minutes at a temperature below optimal growth for antibiotic pre-diffusion.
- Incubate at 25–30°C for 18–24 hours before reading results.
✅ Typical Test Organism Performance
| Test Microorganism | Growth Performance | Antibiotic Assayed |
|---|---|---|
| Saccharomyces cerevisiae | Excellent | Amphotericin B |
| Saccharomyces cerevisiae | Excellent | Nystatin |