Photoproduced Fluorescent Au(I)@(Ag₂/Ag₃)-Thiolate Giant Cluster: An Intriguing Sensing Platform for DMSO and Pb(II)

Abstract

Synergistic evolution of fluorescent Au(I)@(Ag2/Ag3)-thiolate core-shell particles has been made possible under the Sun in presence of the respective precursor coinage metal compounds and glutathione (GSH). The green chemically synthesized fluorescent clusters are giant (∼600 nm) in size and robust. Among all the common water miscible solvents, exclusively DMSO exhibits selective fluorescence quenching (Turn Off) because of the removal of GSH from the giant cluster. Again, only Pb(II) ion brings back the lost fluorescence (Turn On) leaving aside all other metal ions. This happens owing to the strong affinity of the sulfur donor of DMSO for Pb(II). Thus, employing the aqueous solution containing the giant cluster, we can detect DMSO contamination in water bodies at trace level. Besides, a selective sensing platform has emerged out for Pb(II) ion with a detection limit of 14 × 10(-8) M. Pb(II) induced fluorescence recovery is again vanished by I(-) implying a promising route to sense I(-) ion.

Green synthesis of highly fluorescent Au(i)@Ag2/Ag3-thiolate core–shell particles for selective detection of cysteine and Pb(ii)

“…They remain virtually unaffected (84.55 and 88.24 eV respectively) in CyAuAgFL solution. 34,35,[52][53][54][55] But, in the PbAuAgFL solution, appreciable shift of peak position toward higher binding energies indicates gold is in the +3 oxidation state. Now, Pb takes up the role of Au of electron drifting to some extent.…”

Fluorescent nanoprobes for sensing and imaging of metal ions: Recent advances and future perspectives

“…Fluorescence quenching or enhancing of metal NCs by lead ions have been developed for screening Pb 2+ in contaminated lake water samples [126,127] and in DMSO [128]. In addition, an aggregation-induced fluorescence quenching strategy based on coordination of ferric ions and dihydroxyphenylalanine-capped AuNCs has also been applied to the detection of Fe 3+ , with a LOD of 3.5 μM that is close to the MCL (5.4 μM) of Fe 3+ permitted in drinking water by the U.S. EPA.…”

Intriguing cysteine induced improvement of the emissive property of carbon dots with sensing applications

“…Carbon dots (CDs) have been employed for this purpose. Unlike the noble metal nanoclusters 53 or semiconductor quantum dots, 54 the formation of fluorescent carbon dots is quite simpler, cheaper and facile. CDs are conjugated systems that have sp 2 and sp 3 hybridized carbon atoms with plenty of oxygen-containing groups.…”