Probing the Formation of a Seleninic Acid in Living Cells by the Fluorescence Switching of a Glutathione Peroxidase Mimetic

Abstract

Glutathione peroxidase (GPx) is as elenoenzyme that protects cells against oxidative damage.A lthough the formation of aseleninic acid (-SeO 2 H) by this enzyme during oxidative stress has been proposed, aselenic acid has not been identified in cells.H erein, we report that the formation of as eleninic acid can be monitored in living cells by using ar edox-active ebselen analogue with an aphthalimide fluorophore.T he probe reacts with H 2 O 2 to generate the highly fluorescent seleninic acid. The electron withdrawing nature of the -SeO 2 Hm oiety and strong Se···O interactions,w hich prevent the photoinduced electron transfer,a re responsible for the fluorescence.

Discussions of Fluorescence in Selenium Chemistry: Recently Reported Probes, Particles, and a Clearer Biological Knowledge

“…“Rescue” is possible with reduced glutathione. The switching of a molecule from a “turn–on” to “turn–off” was demonstrated and the probe therefore was found to be reversible [ 95 ].…”

“…"Rescue" is possible with reduced glutathione. The switching of a molecule from a "turn-on" to "turn-off" was demonstrated and the probe therefore was found to be reversible [95]. Tian et al deals with probing of H2Se through the use of Se from the pocket of N,Nchelation heterocycle.…”

Bioinspired Selenium‐Nitrogen Exchange (SeNEx) Click Chemistry Suitable for Nanomole‐Scale Medicinal Chemistry and Bioconjugation

“…Ebselen is a famous Org‐Se compound for its excellent glutathione peroxidase (GPx) mimic activity [31] . Notably, the polarized Se−N bond is closely related to its GPx‐like activity and a Se−N exchange (SeNEx) chemistry is involved in its GPx‐like catalytic cycle via the nucleophilic attack of reduced glutathione to the electrophilic Se center to transform the inherent Se−N bond to the Se−S bond (Figure 1B).…”

A non-classical route of efficient plant uptake verified with fluorescent nanoparticles and root adhesion forces investigated using AFM

“…In place of cadmium-based material, copper-based materials are more biocompatible, hence copper selenide is chosen. Owing to the antioxidant role of selenium based amino acid 36 , and the recommendation of copper and selenium as plants micronutrient fairly convince us to use Cu 2-X Se NPs as the model particle 37 . Furthermore, Cu 2-X Se is an isoform of the stable sulphides chalcogenide-family antidote that is preferentially formed by plants to overcome metal ion and metal oxide toxicity 38 – 40 .…”