Cefinase disc test for β - lactamase Cefinase, Bacterial Resistance Detection Cefinase activity determination cefinase disc

1. Product Identity
• INN: Nitrocefin
• CAS: 41906-86-9
• Molecular Formula: C₂₁H₁₆N₄O₈S₂
• Molecular Weight: 516.50 g mol⁻¹
• Appearance: Yellow to orange crystalline solid
• Structure: Chromogenic cephalosporin bearing a 2,4-dinitrostyryl chromophore at the 3-position and a 2-thienyl-acetamido side chain at the 7-position

2. Intended Use / Feature Highlights
• Gold-standard chromogenic substrate for rapid detection of β-lactamase activity in Gram-positive and Gram-negative bacteria.
• Colorimetric read-out: intact nitrocefin is yellow (λmax ≈ 380–390 nm); upon hydrolysis the product shifts to red (λmax ≈ 486–500 nm), allowing naked-eye or spectrophotometric quantification .
• Applications:
– Clinical microbiology: disk tests or broth microdilution for Neisseria gonorrhoeae, Haemophilus influenzae, Staphylococcus spp., Enterococcus spp., Bacteroides spp. .
– Drug-discovery: competitive inhibition assays during development of β-lactamase-resistant antibiotics .
– Iso-electric focusing gels to visualize β-lactamase iso-enzyme patterns .