Liofilchem® VP (KOH) Reagent

The Liofilchem® VP (NaOH) Reagent is a specialized kit for performing the Voges-Proskauer (VP) test, a qualitative biochemical assay used to differentiate members of the Enterobacteriaceae family. This test identifies bacteria capable of producing acetoin (acetylmethylcarbinol) from glucose fermentation, aiding in bacterial identification and diagnostic workflows.

Key Features:

1. Comprehensive Kit:
   • Contains all necessary reagents for the Voges-Proskauer test:
     • 5 vials of sodium alpha-naphthol (10 mL).
     • 5 vials of potassium hydroxide (10 mL).
     • 2 empty dropper bottles for reagent handling.
2. Proven Methodology:
   • Based on Barritt’s modification, which intensifies the Voges-Proskauer reaction by including alpha-naphthol to enhance acetoin detection.
3. Reliable Results:
   • Identifies positive reactions through the development of a pink to bright red color, providing a clear distinction between positive and negative results.
4. Wide Application:
   • Suitable for use with standard microbiological workflows and commercial bacterial identification systems like EnteroPluri-Test.
5. Long Shelf Life:
   • Stable for up to 2 years when stored correctly.

Applications:

1. Clinical Diagnostics:
   • Differentiates Enterobacteriaceae species in clinical specimens.
   • Identifies key pathogens such as Enterobacter cloacae and Escherichia coli.
2. Research:
   • Studies bacterial glucose metabolism and acetoin production pathways.
3. Industrial Microbiology:
   • Supports quality control and contamination monitoring in food and pharmaceutical microbiology.

Specifications:

Test Procedure:

1. Prepare Bacterial Suspension:
   • Inoculate MR-VP broth with a pure culture of the test organism and incubate at 35 ± 2°C for 24–72 hours.
2. Add Reagents:
   • Transfer 1–2 mL of broth culture to a separate test tube.
   • Add 0.6 mL (12 drops) of alpha-naphthol.
   • Add 0.2 mL (4 drops) of potassium hydroxide (40%).
3. Mix and Wait:
   • Shake well to expose the medium to atmospheric oxygen, which is necessary for acetoin oxidation.
   • Wait up to 20 minutes for color development.
4. Interpret Results:
   • Positive Reaction: Development of pink to bright red color.
   • Negative Reaction: No color change or development of a copper color (considered negative).

Quality Control:

Advantages:

1. Rapid and Reliable:
   • Provides results within 20 minutes, expediting identification workflows.
2. Ease of Use:
   • Pre-measured reagents and dropper bottles simplify application.
3. Wide Compatibility:
   • Suitable for standalone VP tests or integration with commercial bacterial identification systems.
4. Consistent Performance:
   • Validated with reference strains to ensure reliability and accuracy.

Storage and Handling:

• Store at 2°C to 8°C, away from light in its original packaging.
• Discard reagents if signs of deterioration or contamination are evident.

Intended Use:

The VP (NaOH) Reagent is an in vitro diagnostic device (IVD) intended for professional use in clinical, research, and industrial microbiology laboratories. It aids in bacterial differentiation and identification as part of diagnostic workflows.

Safety and Precautions:

1. Handle all reagents with care, following safety guidelines.
2. Dispose of waste according to local and national regulations.
3. Do not use expired or visibly damaged reagents.

Product Details:

References:

1. Barritt MM. The Voges-Proskauer reaction: Notes on the alpha-naphthol modification. J Hyg (Lond). 1943.
2. ISO 11133:2014+Amd1:2018+Amd2:2020. Microbiology of food, animal feed, and water.
3. McDevitt S. Methyl Red and Voges-Proskauer Test Protocols. American Society for Microbiology, 2009.

The Liofilchem® VP (NaOH) Reagent is a trusted tool for performing the Voges-Proskauer test, delivering reliable and accurate results in microbiological workflows. Its ease of use and compatibility with diagnostic systems make it indispensable for laboratories worldwide.