3-Hydroxy-2-naphthohydrazide: A Commercially Available Compound for Fluorescence Sensing of Ortho-Vanillin and Vanillin.

Vanillin and ortho-vanillin are the most important flavoring additives used in the food industry at a large scale. Herein, the aggregation-induced emission (AIE) behavior of commercially available 3-hydroxy-2-naphthohydrazide (3HN) was explored and applied for the detection of vanillin and ortho-vanillin. The weakly fluorescent 3HN in DMSO showed fluorescence enhancement at 500 nm with the increase in HEPES or PBS buffer (pH 7.

Fluorescent Switch-on Detection of Cadmium(II) Using Salicylaldehyde-Decorated Gold Nanoclusters.

In this study, salicylaldehyde (SA) conjugated gold nanoclusters were synthesized, characterized, and applied for the fluorescent turn-on sensing of Cd. The trypsin-stabilized fluorescent gold nanocluster (Tryp-AuNCs, λ = 680 nm) was modified with SA to form the spherical-shaped SA_Tryp-AuNCs. After modification, the red-emitting Tryp-AuNCs turned to green-emitting SA_Tryp-AuNCs because of the formation of imine linkage between the -CHO group of SA with the -NH group of functionalized trypsin.

'AIE + ESIPT' Active 2-hydroxy-naphthalene Hydrazone for the Fluorescence Turn-on Sensing of Al.

The aggregation-induced emission (AIE) behaviour of an easy-to-prepare Schiff base 2-hydroxy-naphthalene hydrazone (L) was explored in mixed DMSO/HEPES medium by selecting DMSO as a good solvent, whereas HEPES buffer (HO, 10 mM, pH 7.4) as a poor solvent. The weakly fluorescent L in pure DMSO showed a fluorescence enhancement at 532 nm upon increasing the fraction of HEPES above 70% because of the self-aggregation of L and excited state intramolecular proton transfer (ESIPT) process.

Pyridoxal Derived AIEgen for Fluorescence Turn-off Sensing of Cu and Fe Ions and Fluorescence Imaging of Latent Fingerprints.

Schiff base 4-((E)-((E)-(2-hydroxybenzylidene)hydrazono)methyl)-5-(hydroxymethyl)-2-methylpyridin-3-ol (HSP) was synthesized by condensing vitamin B cofactor pyridoxal with salicylaldehyde hydrazone, and characterized by standard spectroscopic techniques (FT-IR, H NMR, C NMR, and ESI-MS). The solution of HSP in DMSO/HEPES (10 mM, pH = 7.4) mixed solvents with varying HEPES fractions (f) from 0 to 95% showed aggregation-induced emission (AIE).

Mercury Toxicity and Detection Using Chromo-Fluorogenic Chemosensors.

Mercury (Hg), this non-essential heavy metal released from both industrial and natural sources entered into living bodies, and cause grievous detrimental effects to the human health and ecosystem. The monitoring of Hg excessive accumulation can be beneficial to fight against the risk associated with mercury toxicity to living systems. Therefore, there is an emergent need of novel and facile analytical approaches for the monitoring of mercury levels in various environmental, industrial, and biological samples.

Decorating Vitamin B Cofactor over Beta-Cyclodextrin Stabilized Silver Nanoparticles through Inclusion Complexation for Fluorescent Turn-On Detection of Hydrazine.

Contamination of hydrazine has severe effects on the environment and security systems due to its potent toxic and explosive nature. Therefore, the concept of nano and supramolecular chemistry was applied to develop a nanoassembly for the fluorescent turn-on detection of hydrazine. Weakly emissive silver nanoparticles (AgNPs) decorated with beta-cyclodextrin (β-CD) of size ∼7 nm (β-CD-AgNPs) was synthesized, characterized, and interacted with pyridoxal 5'-phosphate (PLP).

An aggregation-induced emission active vitamin B cofactor derivative: application in pH sensing and detection of latent fingerprints.

Aggregation-induced emission (AIE) properties of an easy-to-prepare and structurally planar Schiff base derivative of the vitamin B6 cofactor pyridoxal (L) were investigated in DMSO-H2O mixed solvents. Compound L showed weak fluorescence (λem = 425 nm) in pure DMSO, but increasing the fraction of water in DMSO resulted in a significant fluorescence enhancement at 575 nm due to the restriction of intramolecular rotation (RIR) of L upon aggregation. SEM analyses revealed the formation of hairy micelle-like or needle-shaped self-assemblies/aggregates of L.

A multi-analyte selective dansyl derivative for the fluorescence detection of Cu(ii) and cysteine.

A new multi-analyte selective fluorescence chemosensor DA was synthesized by a simple one pot reaction between dansyl chloride and 2-aminobenzohydrazide in the presence of a base. In DMSO : H2O (1 : 1, v/v), the fluorescence of DA at 483 nm was blue shifted and enhanced at 474 nm along with a new shoulder peak appearing at 411 nm selectively in the presence of Cu2+ among the other tested metal ions due to the chelation enhanced fluorescence (CHEF) effect. Without any noticeable interference from potentially competitive metal ions, sensor DA can detect Cu2+ down to 9.