L-cysteine capped CdSe as sensitive sensor for detection of trace lead ion in aqueous solution

Facile Synthesis of Polysulfoaminoanthraquinone Nanosorbents for Rapid Removal and Ultrasensitive Fluorescent Detection of Heavy Metal Ions

“…Compared with other typical fluorescent Pb(II) chemosensors, − the PSA-based “turn-off” quenching response chemosensor exhibits both ultrahigh sensitivity and high selectivity at the same time. The PSA probe shows a very superior detection limit down to 1.0 × 10 −10 M that is at least 2 orders of magnitude better than that of other synthetic organic compounds and other polymer-based probes.…”

“…The Pb(II) fluorescent probes reported thus far include macrocyclic compounds linking fluorophore, [17][18][19] rhodamine derivatives, 20 DNA biomolecule, [21][22][23][24] and organicinorganic hybrid fluorescent materials such as ferrocene 25 and L-cysteine capped CdSe. 26 However, there still remain some drawbacks like unsatisfactory detection limit (ordinarily 10 -7 -10 -9 M), severe interference by other metal ions, especially Hg(II) and Cd(II), 27 and/or tedious and sophisticated preparation of the probes. Therefore, the design and synthesis of Pb(II) chemosensors which have excellent comprehensive performance including ultrahigh sensitivity and high selectivity toward Pb(II) even at a trace level, and low cost, still face challenges.…”

“…Fluorescent probes for sensing and monitoring heavy metal ions have been attracting more and more attention due to their accuracy and simplicity in the past decade. The Pb(II) fluorescent probes reported thus far include macrocyclic compounds linking fluorophore, − rhodamine derivatives, DNA biomolecule, − and organic−inorganic hybrid fluorescent materials such as ferrocene and l -cysteine capped CdSe . However, there still remain some drawbacks like unsatisfactory detection limit (ordinarily 10 −7 −10 −9 M), severe interference by other metal ions, especially Hg(II) and Cd(II), and/or tedious and sophisticated preparation of the probes.…”

Synthesis of hydrophilic Ag2Se quantum dots optically optimized by multivariate strategies: an easy one-pot approach

“…Although coating the nanocrystals of these semiconductors with a monolayer of a non-toxic semiconductor is an interesting alternative to promote the biocompatibility of those systems, the controlled synthesis of core/shell structures remains a challenge, and the reliability of their application in large mammals remains to be proven. 2,3 In this context, silver chalcogenides QDs (Ag 2 X, X = S, Se, and Te) emerge as a promising alternative to the mentioned NIR-emitting QDs because, in addition to not containing a Department of Fundamental Chemistry, Federal University of Pernambuco, Recife, elements of high toxicity, they have significantly low solubility product constants (K sp = 2.0 Â 10 À64 and 6.3 Â 10 À50 for Ag 2 Se and Ag 2 S, 1 respectively) compared to those containing heavy metal ions (K sp = 6.3 Â 10 À36 , 8.0 Â 10 À27 , 7.9 Â 10 À43 and 9.0 Â 10 À29 for CdSe, CdS, PbSe, and PbS, respectively), 1,6,7 leading to minimal amount of Ag + ions released into the biological surroundings. 1,8 Ag 2 X are semiconductors with very narrow band gaps (0.67, 1.1, and 0.15 eV, respectively, for bulk Ag 2 Te, Ag 2 S, and Ag 2 Se), which justifies their respective PLs reaching the NIR region.…”

Metal ions optical sensing by semiconductor quantum dots

“…This sensing strategy was also used for other metal ions sensing, such as TG capped CdTe QDs for Mn 2+ sensing, 97 TGA capped CdTe for Co 2+ sensing 33,99 and Pb 2+ sensing, 94,95 thiol-DAB dendrimers coupled CdSe 93 and Cys-capped CdSe for Pb 2+ sensing. 92 In addition, Cys capped CdTe/ZnS QDs were applied to sensitively detect Ni 2+ , due to the formation of NiS on the QD surface, with a detection limit of 0.59 nM. 98 3b.…”