Regiodependent Luminescence Quenching of BiotinylatedN-Sulfonyl-acridinium-9-carboxamides by Avidin

Abstract

[reaction: see text] Biotin was conjugated to chemiluminescent N-sulfonylacridinium-9-carboxamides at the N-10 or 9-position carboxamide. Upon binding to avidin, the light output of the N-10 derivative (8) was quenched up to 92% upon triggering with basic peroxide, while the 9-position carboxamide conjugate (9) was quenched only 33%. The utility of this effect was demonstrated in a model homogeneous chemiluminescence assay.

Ruthenium(II)−Phenanthroline−Biotin Complexes: Synthesis and Luminescence Enhancement upon Binding to Avidin

“…This is primarily due to the strength of the interaction between the ligand and the protein ( K d = 1.3 × 10 -15 M) and to the presence of four binding sites for biotin on avidin, which in turn allows for the cross-linking of different biotinylated molecules (). Bioanalytical applications based on the biotin/avidin interaction have typically used enzymatic reactions, radiolabeling techniques, and fluorescence for detection/visualization ( − ). Of these, fluorescence-based assays are some of the most straightforward and rapid detection techniques ( − ).…”