Thermo Scientific™ Beta Lactam Disk

A rapid, acidometric method to detect beta lactamase production by certain strains of bacteria using a reagent-impregnated Beta Lactam Disk.

Supplier:  Thermo Scientific™ R261605

Catalog No. R261605

Description

Detect beta lactamase production by certain strains of Haemophilus sp., Neisseria gonorrhoeae, and Staphylococcus sp. using a reagent-impregnated Thermo Scientific™ Remel™ Beta Lactam™ Disk. Several acidometric methods using phenol red as an indicator and penicillin as a substrate have been published^{12, 1-3}. In 1972, O'Callaghan et al. described a beta lactamase procedure using chromogenic cephalosporin as a substrate¹². Cresol red and bromocresol purple have also been incorporated as indicators in acidometric methods with penicillin as the substrate^13,4.

Certain gram-positive and gram-negative bacteria produce an important class of enzymes called beta-lactamases, which may be mediated by genes on plasmids or chromosomes. These enzymes confer resistance to many penicillin antibiotics by cleaving the beta-lactam ring of penicillin and cephalosporin antibiotics, resulting in inactivation of these drugs. They are capable of inactivating “penicillinase-labile-penicillins”, such as amoxicillin, ampicillin, penicillin, carbenicillin, mezlocillin, and piperacillin. β-lactamases thus play a key role in bacterial resistance to beta-lactam agents, and detection of their presence can provide useful information⁵.

• Ready to Use: Reagent impregnated disk
• Rapid Test: Results are obtained within 30 minutes. Reaction time for the positive test is 1-10 minutes.
• Easy-to-identify:
  • Positive test: Color change from blue to yellow indicates the production of beta lactamase.
  • Negative test: No color change indicates no beta lactamase production.

Beta lactamase production by certain strains of Neisseria gonorrhoeae, Haemophilus influenzae, and Staphylococcus aureus has been demonstrated^6-13. Several clinical tests have been developed for the detection of beta lactamases.

The Beta Lactam Disk is impregnated with benzylpenicillin which contains a beta lactam ring. When the beta lactamase enzyme is produced by an organism, the beta lactam ring of benzylpenicillin is hydrolyzed to form penicilloic acid. This cleavage of the beta lactam ring inactivates the antibiotic. The resulting fall in pH is indicated by the bromocresol purple indicator changing from purple to yellow.

Not all products are available for sale in all territories. Please inquire.

Remel™ and Oxoid™ products are now part of the Thermo Scientific brand.

Specifications

• Content And Storage: 2°C to 8°C
• Detectable Analytes: beta-lactamase (Haemophilus species, N. gonorrhoeae,Staphylococci)
• Quantity: 25 Disks/Vial

• Description: Beta Lactam™ Reagent Disk
• Format: Vial