Thermo Scientific™ Remel™ Nitrocefin Disk, 25/Vial

Thermo Scientific™ Remel™ Nitrocefin Disks are ready-to-use chromogenic reagent disks designed for the rapid qualitative detection of β-lactamase production in clinically significant bacteria. β-lactamase enzymes confer resistance to penicillins and cephalosporins by hydrolyzing the β-lactam ring of these antibiotics. Early and accurate detection of β-lactamase activity is critical in antimicrobial susceptibility workflows and infection control management.

These disks conform to CLSI performance standards for antimicrobial disk susceptibility testing and are CE marked for professional laboratory use.

Principle of the Method

The test utilizes nitrocefin, a chromogenic cephalosporin substrate.

When β-lactamase is present:

• The enzyme hydrolyzes the β-lactam ring of nitrocefin.
• Hydrolysis converts nitrocefin from a pale yellow compound to a pink/red product (cephalosporanic acid derivative).
• The visible color change indicates β-lactamase production.

Organisms that do not produce β-lactamase will not alter the disk color within the prescribed time limit.

This chromogenic method offers greater sensitivity and ease of interpretation compared to traditional iodometric or acidimetric techniques.

Target Organisms

Nitrocefin Disks are commonly used to detect β-lactamase production in:

• Neisseria gonorrhoeae
• Haemophilus influenzae
• Moraxella catarrhalis
• Staphylococcus species
• Enterococcus species
• Anaerobic bacteria

Key Features

• Ready-to-use nitrocefin-impregnated disks
• Rapid colorimetric results
• Clear visual interpretation (yellow to pink color change)
• Suitable for both aerobic and anaerobic organisms
• Conforms to CLSI standards (M2-A8 and M11-A5)
• CE marked for professional laboratory use

Test Interpretation

Positive Result:

Rapid change from pale yellow to pink/red, indicating β-lactamase production.

Negative Result:

No color change within the recommended test time.

Product Specifications

Applications

• Clinical microbiology laboratories
• Hospital diagnostic testing
• Rapid screening for antibiotic resistance
• Confirmation of penicillinase and cephalosporinase production
• Support of antimicrobial stewardship programs

Storage and Handling

Store at 2°C to 8°C.

Allow disks to reach room temperature before use.

For professional laboratory use only.

Thermo Scientific Remel Nitrocefin Disks provide a rapid, reliable, and easy-to-interpret method for detecting β-lactamase production in clinically relevant bacteria. The chromogenic color change system enables efficient confirmation of antibiotic resistance mechanisms, supporting accurate identification and appropriate antimicrobial therapy decisions.