Presentation day

Tuesday  10:00 AM

TITLE

Reaction-based Indicator displacement Assay (RIA)

Abstract

Peroxynitrite a combination of nitric oxide and the superoxide radical anion, is a strong
oxidant with a very short lifetime (10 ms) in physiological and pathological processes. Peroxynitrite is a
highly reactive molecule involved in cell signal transduction. Many biomolecules are oxidised and/or
nitrated by peroxynitrite-derived radicals, including DNA, tyrosine residues, thiols, and unsaturated fattyacid-
containing phospholipids. Endogenous peroxynitrite formation, and associated protein nitration, has
been implicated in Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral
sclerosis, viral myocarditis, septic shock, cardiac allograft, transplant coronary artery disease, idiopathic
dilated cardiomyopathy, atrial fibrillation, hypercholesterolemia, atherosclerosis, hypertension, diabetes,
diabetic nephropathy, and traumatic brain injury. Therefore, peroxynitrite has captured the attention of
many groups who seek effective and selective approaches for its detection.
Using the self-assembly of aromatic boronic acids with Alizarin Red S (ARS), we developed a new
chemosensor for the selective detection of peroxynitrite. Phenylboronic acid (PBA), benzoboroxole (BBA)
and 2-(N,N-dimethylaminomethyl)phenylboronic acid (NBA) were employed to bind with ARS to form selfassembled
probes. The ARS–NBA system preferably reacts with peroxynitrite over hydrogen peroxide and
other ROS/RNS due to the protection of the boron via the solvent-insertion B–N interaction. Our simple
system produces a visible colorimetric change and on–off fluorescence response towards peroxynitrite. By
coupling a chemical reaction that leads to an indicator displacement, we have developed a new sensing
strategy, referred to herein as RIA (Reaction-based Indicator displacement Assay).