Liofilchem™ Hydrogen Sulfide Test, 30 Tests

Rapid Biochemical Test for Detection of Hydrogen Sulfide Production in Bacterial Isolates

The Liofilchem® H2S Rapid Test is a ready-to-use, tube-based assay designed for the rapid identification of hydrogen sulfide (H₂S) production by bacterial isolates. Utilizing a desiccated medium with sodium thiosulfate and ferrous ammonium sulfate, this test detects the enzymatic activity associated with H₂S-producing organisms through the formation of a black ferrous sulfide precipitate. It is an essential diagnostic tool for differentiating key members of the Enterobacteriaceae family, such as Proteus, Salmonella, and Citrobacter.

Key Features & Benefits

✅ Rapid Identification

• Results in as little as 4–24 hours
• Visual interpretation via black precipitate formation

✅ User-Friendly Format

• Pre-filled tubes containing desiccated media
• Requires only 0.3 mL of physiological solution for reconstitution

✅ Specific & Reliable

• Ferrous ammonium sulfate ensures high specificity for H₂S
• Validated against reference strains including Salmonella Typhimurium and Proteus mirabilis

✅ Compact and Efficient

• Overlay with sterile mineral oil to create an anaerobic environment
• Enables efficient batch testing in clinical and food safety laboratories

✅ In Vitro Diagnostic Use (IVD)

• Conforms to EU IVD regulations and internal quality standards
• One-year shelf life when stored between 2–8°C

Applications

• Clinical Diagnostics: Identification of H₂S-producing pathogens in patient samples
• Food & Water Microbiology: Detection of sulfide-producing bacteria in contamination screening
• Veterinary Microbiology: Pathogen differentiation in animal infections
• Teaching & Research: Microbial biochemistry studies involving sulfur metabolism

Test Principle

The test medium contains sodium thiosulfate as a sulfur source and ferrous ammonium sulfate as an H₂S indicator. Upon bacterial metabolism, hydrogen sulfide gas is released, reacting with the iron salt to form an insoluble black ferrous sulfide precipitate. A black color indicates a positive result, while no color change indicates a negative result.

Procedure Summary

1. Bring test tubes to room temperature.
2. Add 0.3 mL of sterile physiological solution (0.85% NaCl) to each tube.
3. Inoculate heavily with a fresh pure culture.
4. Overlay with 2–3 drops of sterile mineral oil.
5. Incubate at 35 ± 2°C for up to 24 hours.
6. Observe for black precipitate formation at 4h and 24h timepoints.

Interpretation of Results

Performance & Quality Control

Storage & Shelf Life

• Store between 2–8°C in original packaging
• Avoid heat and light exposure
• Shelf life: 1 year

Ordering Information

Why Choose Liofilchem® H2S Rapid Test?

• Trusted brand with ISO-certified quality systems
• Streamlines routine microbiology workflows
• Compatible with clinical and industrial protocols
• Eliminates false positives from pH interference
• Backed by peer-reviewed validation

The Liofilchem® H2S Rapid Test is a reliable, efficient, and cost-effective tool for detecting hydrogen sulfide production in bacterial isolates. Its straightforward design, clear visual readout, and compatibility with routine laboratory workflows make it an ideal choice for microbiological laboratories seeking rapid preliminary identification of enteric and non-enteric pathogens. When used in combination with other biochemical and morphological tests, the H2S Rapid Test supports accurate differentiation of clinically and environmentally relevant bacteria.

For laboratories prioritizing speed, accuracy, and simplicity, the Liofilchem® H2S Rapid Test provides a proven solution for H₂S detection.