Ultrasensitive Reagent for Ratiometric Detection and Detoxification of iAs^III in Water and Mitochondria

Abstract

Toxicity induced by inorganic arsenic as AsO3 3– (iAs III ) is of global concern. Reliable detection of the maximum allowed contaminant level for arsenic in drinking water and in the cellular system remains a challenge for the water quality management and assessment of toxicity in the cellular milieu, respectively. A new Ir­(III)-based phosphorescent molecule (AS-1; λExt = 415 nm and λEms = 600 nm, Φ = 0.3) is synthesized for the selective detection of iAs III in an aqueous solution with a ratiometric luminescence response even in the presence of iAs V and all other common inorganic cations and anions. The relatively higher affinity of the thioimidazole ligand (HPBT) toward iAs III led to the formation of a fluorescent molecule iAs V –HPBT (λExt = 415 nm and λEms = 466 nm, Φ = 0.28) for the reaction of iAs III and AS-1. An improved limit of quantitation (LOQ) down to 0.2 ppb is achieved when AS-1 is used in the CTAB micellar system. Presumably, the cationic surfactants favor the localization of AS-1@CTABMicelle in mitochondria of MCF7 cells, and this is confirmed from the images of the confocal laser fluorescence scanning microscopic studies. Importantly, cell viability assay studies confirm that AS-1@CTABMicelle induces dose-dependent detoxification of iAs III in live cells. Further, luminescence responses at 466 nm could be utilized for developing a hand-held device for the in-field application. Such a reagent that allows for ratiometric detection of iAs III with LOQ of 2.6 nM (0.5 ppb) in water, as well as helps in visualizing its distribution in mitochondria with a detoxifying effect, is rather unique in contemporary literature.

Functionalized Fluorescent Nanostructures Generated from Self-Assembly of a Cationic Tripeptide Direct Cell-Selective Chemotherapeutic Drug Delivery

“…Of particular interest in the areas of drug delivery and biosensor design is the development of nanoparticles with intrinsic fluorescence which would allow for the monitoring of drug delivery and release in real time. − The integration of fluorophores or QDs into conventional non-fluorescent drug delivery systems has been proposed for imaging purposes in biomedicine. , However, organic luminescent dyes are highly susceptible to photobleaching and do not allow for bioconjugation at specific sites. Similarly, QDs suffer from substantial cytotoxicity that restricts their use in biomedical applications.…”

Two Zero‐Dimensional In3+‐Based Hybrid Halides: Single‐Component Materials Showing Bluish‐White‐Light Emission

“…Such as organic‐inorganic halide hybrids (OIHs), [11–13] all‐inorganic semiconductor nanocrystals, [14] organic/polymeric emitters [15–17] and so on, [18–21] many materials with broadband emission characteristics have been discovered. As one of these candidates, OIHs have been considered to be competitive, owing to their tunable structure and photoluminescence features [22–25] .…”

“…[6] In contrast, single-component white-light emitters have shown considerable application value in LEDs, because of their more stable color rendering, simpler synthesis process and lower cost. [7][8][9][10] Such as organic-inorganic halide hybrids (OIHs), [11][12][13] allinorganic semiconductor nanocrystals, [14] organic/polymeric emitters [15][16][17] and so on, [18][19][20][21] many materials with broadband emission characteristics have been discovered. As one of these candidates, OIHs have been considered to be competitive, owing to their tunable structure and photoluminescence features.…”