Covidyte™ IF670 is a peptide substrate containing 12 amino acid sequence (VNSTLQSGLRKM) that can be cleaved by coronavirus proteases. The dark-FRET peptide contains Tide Quencher™ 5 (TQ5) as a quencher and iFluor® 670 as a fluorescent donor on the N-and C-terminals respectively where the fluorescence of iFluor® 670 is effectively quenched by TQ5 when the peptide is intact. When the peptide is hydrolyzed by coronavirus proteases, the iFluor® 670 fragment generates significantly enhanced fluorescence since its fluorescence is no longer quenched by TQ5. The activity of coronavirus proteases can be effectively monitored by the fluorescence intensity of iFluor® 670. Covidyte™ IF670 is a robust high throughput screening tool for searching inhibitors of coronavirus proteases. Comparing to the commonly used EDANS substrates (such as Covidyte™ ED450), the iFluor® 670 substrate has much stronger and longer fluorescence that is less interfered by coloured compounds that often cause false positive hits.

• MW 3067.69