Turn-on Fluorescent Chemosensor Based on an Amino Acid for Pb(II) and Hg(II) Ions in Aqueous Solutions and Role of Tryptophan for Sensing

N-doped carbon dots synthesized by rapid microwave irradiation as highly fluorescent probes for Pb2+ detection

New NCDs were obtained and exhibit highly sensitive response to Pb²⁺ which could be applied to real sample detection.

Fluorescent and colorimetric sensors for environmental mercury detection

The development of fluorescent and colorimetric sensing strategies for environmental mercury is described.

Selective fluorescence sensing of salicylic acids using a simple pyrenesulfonamide receptor

The highest change in relative intensity of probe 3 among the probes 2–5 with 3,5-DNSA demonstrated the significance of sulfonamide N–H and imidazole C2–H with the highest association constant and complete quenching.

A single hybrid optical sensor based on nanoporous silica type SBA-15 for detection of Pb2+and I−in aqueous media

Simple two-steps post synthesis procedure achieved the functionalized nanoporous SBA-15 as a single hybrid optical sensor for detecting Pb²⁺and I⁻ions in aqueous media.

Highly selective colorimetric and fluorescent detection for Hg2+ in aqueous solutions using a dipeptide-based chemosensor

A dipeptide-based chemosensor selectively and sensitively detected Hg^II in aqueous solutions by colorimetric change and fluorescent change.

Highly sensitive colorimetric detection of HgII and CuII in aqueous solutions: from amino acids toward solid platforms

A chemosensor (NBD-H) based on an amino acid with 7-nitro-2,1,3-benzoxadiazole was used for selective detection of Hg^II and Cu^II among 15 metal ions in aqueous solutions by a colorimetric change and fluorescence change.

A novel peptide-based fluorescent chemosensor for measuring zinc ions using different excitation wavelengths and application in live cell imaging

A novel peptide-based fluorescent chemosensor containing both tryptophan and a dansyl fluorophore has been designed to detect Zn²⁺ in 100% aqueous solution and living cells via two pathways including fluorescence resonance energy transfer and chelation enhanced fluorescence.

Design strategies for lab-on-a-molecule probes and orthogonal sensing

This review highlights the currently exploited working concepts of lab-on-a-molecule probes, with a particular focus on what is required for multianalyte detection and quantification in competitive assays. Both, chemosensor and chemodosimeter approaches are considered. The multifaceted design strategies and the orthogonal protocols are evaluated in order to identify and categorise the successful conceptions and to single out unknown territory and challenges for future work.

A new 3,5-bisporphyrinylpyridine derivative as a fluorescent ratiometric probe for zinc ions

A new 3,5-disubstituted pyridine with two porphyrin moieties was prepared through an efficient synthetic approach involving 2-formyl-5,10,15,20-tetraphenylporphyrin (1), piperidine, and catalytic amounts of [La(OTf)3]. 3,5-Bis(5,10,15,20-tetraphenylporphyrin-2-ylmethyl)pyridine (2) was fully characterized and its sensing ability towards Zn(2+), Cu(2+), Hg(2+), Cd(2+), and Ag(+) was evaluated in solution by absorption and fluorescence spectroscopy and in gas phase by using matrix-assisted laser desorption/ionization (MALDI)-TOF mass spectrometry. Strong changes in the ground and excited state were detected in the case of the soft metal ions Zn(2+), Cd(2+), Hg(2+), and Cu(2+). A three-metal-per-ligand molar ratio was obtained in all cases and a significant ratiometric behavior was observed in the presence of Zn(2+) with the appearance of a new band at 608 nm, which can be assigned to a metal-to-ligand charge transfer. The system was able to quantify 79 ppb of Zn(2+) and the theoretical calculations are in accordance with the stoichiometry observed in solution. The gas-phase sensorial ability of compound 2 towards all metal ions was confirmed by using MALDI-TOF MS and in solid state by using polymeric films of polymethylmethacrylate (PMMA) doped with ligand 2. The results showed that compound 2 can be analytically used to develop new colorimetric molecular devices that are able to discriminate between Hg(2+) and Zn(2+) in solid phase. The crystal structure of Zn(II) complex of 3,5-bisporphyrinylpyridine was unequivocally elucidated by using single-crystal X-ray diffraction studies.

Cysteine-based fluorescence “turn-on” sensors for Cu2+ and Ag+

Amino acid cysteine was transformed to fluorescent turn-on sensors for Cu⁺² and Ag⁺. The metal ion binding was studied in detail by spectroscopic, microscopic, calorimetric and computational methods.

An aggregation-induced emission based “turn-on” fluorescent chemodosimeter for the selective detection of Pb2+ ions

An aggregation-induced emission (AIE) based “turn-on” fluorescent chemodosimeter for selective detection of Pb²⁺ ions has been developed. The probe is a phosphate functionalized tetraphenylethylene derivative and the resulting lead–TPE complex has very low solubility in working solvent and triggers AIE and shows a low detection limit of 10 ppb.

Palladium-catalyzed P(O)R2 directed C–H arylation to synthesize electron-rich polyaromatic monophosphorus ligands

A novel pathway for the synthesis of polyaromatic monophosphorus ligands via the P(O)R₂ directed palladium-catalyzed arylation of (diisopropylphosphoryl)biphenyl skeleton derivatives was discovered.

Ratiometric fluorescence sensing of sugars via a reversible disassembly and assembly of the peptide aggregates mediated by sugars

An amphiphilic dipeptide (1) bearing pyrene and phenylboronic acid was demonstrated as a unique example of a ratiometric sensing system for sugars by reversibly converting the peptide aggregates into the monomer form of the complex with sugars in aqueous solutions.

Ratiometric fluorescence chemosensor based on tyrosine derivatives for monitoring mercury ions in aqueous solutions

Ratiometric fluorescent chemosensors1and2were synthesized based on tyrosine amino acid derivatives with a pyrene fluorophore.