A dual-function fluorescence 'turn-on' probe that allows Zn (II) bioimaging and quantification of water in the organic solvent.

Herein, a Eugenol-derived fluorescence 'turn-on' probe FLHE was synthesized by condensing 2-((3-(trifluoromethyl)phenyl)amino)benzohydrazide with 5-allyl-2-hydroxy-3-methoxybenzaldehyde. FLHE demonstrated very low fluorescence in the studied organic solvents of varying polarities. However, upon titration with Zn in HEPES buffer (pH = 7.

Exploration of Molecular Structure, DFT Calculations, and Antioxidant Activity of a Hydrazone Derivative.

The hydrazine derivatives are known to possess several biological activities including anticancer, antibacterial and anti-fungal, anticonvulsant, and antioxidant. This communication presents the synthesis, X-ray crystal structure analysis, DFT calculations, cell cytotoxicity, and antioxidant activity of the Schiff base 4,4'-((1E,1'E)-hydrazine-1,2-diylidenebis(ethan-1-yl-1-ylidene))bis(benzene-1,3-diol) (compound ). We have also isolated the side product compound and characterized it using single X-ray crystallography.

Elimination Reaction-Based Benzimidazole Probe for Cysteine Detection and Its Application in Serum Sample Analysis.

Benzimidazole-based compound 2-(-tolyl)-1-benzo[d]imidazole () and its derivative probe have been synthesized for the highly selective detection and quantification of Cys in human serum. The photophysical properties of and compound were evaluated by UV-vis absorption and fluorescence spectroscopy. showed high selectivity and sensitivity for Cys among tested analytes, including amino acids, anions, and cations.

Exploration of highly selective fluorogenic 'on-off' chemosensor for H PO ions: ICT-based sensing and ATPase activity profiling.

In this study, the recognition contour of Chemosensor 1 was investigated using semiaqueous methanol (X , mole fraction = 0.31) for a range of anions and bioactive species. Host-receptor signalling based on the internal charge transfer mechanism for Chemosensor 1 was explored and reported.

High Performance Fluorescent Turn-On Probe for Amitriptyline Based on Hybrid Nanoassembly of Organic-Inorganic Nanoparticles.

Fluorescence methods have gained enormous attention due to their ease in use, simplicity, selectivity and sensitivity. Fluorescent chemosensors respond instantly by converting molecular recognition to fluorescent signals. The consumption of pharmaceutical products by living beings is on great increase.

Chemosensors for biogenic amines and biothiols.

There is burgeoning interest among supramolecular chemists to develop novel molecular systems to detect biogenic amines and bio-thiols in aqueous and non-aqueous media due to their potential role in biological processes. Biogenic amines are biologically important targets because of their involvement in the energy metabolism of human biological systems and their requirement is met through food and nutrition. However, the increasing instances of serious health problems due to food toxicity have raised the quality of food nowadays.

Fe(III) conjugated fluorescent organic nanoparticles for ratiometric detection of tyramine in aqueous medium: A novel method to determine food quality.

A tetrapodal receptor was synthesized and was processed into fluorescent organic nanoparticles (FONs) for determination of important analytes in aqueous medium. The receptor was fully characterized using characterization techniques. Recognition behavior of FONs towards different metal ions was investigated with fluorescence spectroscopy, amongst them Fe ions showed quenching behavior in the emission spectra.

A novel terephthalaldehyde based turn-on fluorescent chemosensor for Cu and its application in imaging of living cells.

A new terephthaldehyde-based chemosensor 1 bearing an aminophenol recognition unit has been synthesized and applied to the fluorescent sensing of metal ions. Molecular system 1 acts as a highly selective and sensitive fluorescence turn-on sensor for Cu. The sensing mechanism has been explored.

A new Schiff base as a turn-off fluorescent sensor for Cu and its photophysical properties.

A new Schiff base receptor 1 was synthesized and its photophysical properties were investigated by absorption, emission and excitation techniques. Furthermore, its chromogenic and fluorogenic sensing abilities towards various metal ions were examined. Receptor 1 selectively detects Cu ion through fluorescence quenching and detection was not inhibited in the presence of other metal ions.

Highly selective optical and reversible dual-path chemosensor for cyanide detection and its application in live cells imaging.

A new biocompatible fluorescent receptor 1 was synthesized by conjugating diaminomaleonitrile (DMN) with benzothiazole unit, and characterized by single X-ray. In DMF/water (1:1, v/v), the receptor 1 showed a selectivity turn-on fluorescence at 517nm in the presence of CN. Receptor 1 showed a detection limit down to 0.

Selective ciprofloxacin antibiotic detection by fluorescent siderophore pyoverdin.

Fluorescent siderophore pyoverdin (PVD) was produced from a soil isolate Pseudomonas monteilii strain MKP 213. The PVD was purified near to homogeneity and applied for the fluorescent chemosensing of various antibiotics in aqueous solution (pH=7.0).

A novel zinc(II) and hydrogen sulphate selective fluorescent "turn-on" chemosensor based on isonicotiamide: INHIBIT type's logic gate and application in cancer cell imaging.

We have developed a novel isonicotiamide-based fluorescent "turn-on" chemosensor 1 for the selective detection of Zn(2+) and HSO4(-). The sensor 1 can detect Zn(2+) and HSO4(-) with a detection limit down to the nanomolar level by forming a complex in 1 : 1 stoichiometry in the presence of other anions and 2 : 1 in presence of cations in aqueous solution. Density functional theory calculations on 1 and the 1-Zn(2+)/HSO4(-) complexes are consistent with the experimental results.

Acetate selective fluorescent turn-on sensors derived using vitamin B6 cofactor pyridoxal-5-phosphate.

Two new Schiff base receptors have been synthesized by condensation of pyridoxal-5-phosphate with 2-aminophenol (L(1)) or aniline (L(2)). In DMSO, the receptors showed both chromogenic and 'turn-on' fluorescence responses selectively in the presence of AcO(-) and F(-). However, in mixed DMSO-H2O medium, the receptors showed AcO(-) selective 'turn-on' fluorescence without any interference from other tested anions including F(-).

Fluorescence Chemosensor for HSO4 (-) Ion Based on Pyrrole-Substituted Salicylimine Zn (2+) Complex: Nanomolar Detection.

A novel pyrrole-substituted salicylimine zinc (II) ion complex has been synthesized and evaluated its anion binding affinity. The probe 4 has high selectivity for HSO4 (-) over other anions in CH3OH:H2O (70:30, v/v) solvent system. The emission intensity of 4 was quenched upon addition of HSO4 (-).

Virgin silver nanoparticles as colorimetric nanoprobe for simultaneous detection of iodide and bromide ion in aqueous medium.

A simple colorimetric nanoprobe based on virgin silver nanoparticles (AgNPs) was developed for the selective detection of iodide and bromide ions via aggregation and anti-aggregation mechanism. With addition of I(-) ions, virgin AgNPs, in presence of Fe(3+), showed perceptible color change from yellow to colorless along with disappearance of surface plasmon resonance (SPR) band of AgNPs at 400 nm. But in presence of Cr(3+), AgNPs turned yellow upon addition of I(-)and Br(-) anions.

Pyrrole-coupled salicylimine-based fluorescence "turn on" probe for highly selective recognition of Zn²⁺ ions in mixed aqueous media: Application in living cell imaging.

Cation sensing behaviour of a pyrrole-based derivative (2-hydroxyl 3 methyl 6 isopropyl benzaldehyde}-3,4-dimethyl-1H-pyrrole-2-carbohydrazide (receptor 3) has been explored and is found to be selective towards Zn(2+) over a variety of tested cations. The receptor 3 has shown high selectivity and sensitivity towards Zn(2+) over the other alkali, alkaline earth and transition metal ions. In the presence of Zn(2+), absorption band of receptor 3 has shown the red shift.

A novel phthalazine based highly selective chromogenic and fluorogenic chemosensor for Co(2+) in semi-aqueous medium: application in cancer cell imaging.

A new phthalazine based chemosensor was developed for the highly selective and sensitive detection of Co(2+) in the mixed solvent system, CH3CN-H2O (1 : 1, v/v). In the presence of Co(2+), the colour of the solution changed from yellow to green; the absorption maxima of was red-shifted from 383 nm to 435 nm, and the fluorescence of at 550 nm was significantly enhanced. The sensor showed a detection limit down to 25 nM by forming a complex species with Co(2+) in 1 : 1 stoichiometry.

A highly selective fluorescent 'turn-on' chemosensor for Zn(2+) based on a benzothiazole conjugate: their applicability in live cell imaging and use of the resultant complex as a secondary sensor of CN(-).

A benzothiazole derivative linked "off-on" multi-responsive and selective chemosensor has been synthesized and evaluated for cation recognition properties. The receptor shows a high sensitivity and selectivity for Zn(2+) through a 'turn-on' fluorescence response over the other tested cations with a detection limit as low as 0.67 μM.

Fluorogenic ratiometric dipodal optode containing imine-amide linkages: exploiting subtle thorium (IV) ion sensing.

The (13E,19E)-N1',N3'-bis[4-(diethylamino)-2-hydroxybenzylidene]malonohydrazide (L) has been developed for the detection of Th(4+) ions using dual channel signalling system. The UV-vis absorbance and fluorescence spectroscopic data revealed the formation of L-Th(4+) complex in 1:1 equilibrium. The density functional theory (DFT) also confirms the optimum binding cavity for the recognition of metal ion.

A fluorescent and colorimetric sensor for nanomolar detection of Co2+ in water.

A new disulfide-based, imine-linked fluorescent receptor 1 was processed into organic nanoparticles (ONPs) with an average particle size of 79 nm. The photophysical properties of the ONPs were evaluated by UV/Vis absorption spectroscopy. Receptor 1 selectively recognized Co(2+) ions in water with a detection limit down to 88 nm.

Ratiometric fluorescent scaffold giving discrete response towards iodide ion: a combined experimental and DFT study.

A novel ratiometric fluorescent receptor (Z)-2-(4-[diethylamino]-2-hydroxybenzylideneamino) pyridine-3-carbaldehyde (3) bearing one phenolic OH and one aldehyde group as recognition sites was synthesized and characterized. The anion recognition behaviour of receptor 3 was evaluated by various spectroscopic (UV-visible, fluorescence and (1) H nuclear magnetic resonance) methods and was validated by computational studies. The receptor showed fast response time, excellent selectivity and reproducibility towards iodide ion detection among the other surveyed anions, with a binding constant of 6.

Highly selective turn-on fluorescent sensor for nanomolar detection of biologically important Zn2+ based on isonicotinohydrazide derivative: application in cellular imaging.

A new Zn(2+) selective chemosensor (3) was synthesized by condensation of commercially available substituted salicylaldehyde and isonicotinohydrazide, and characterized by single crystal X-ray crystallography. Receptor 3 with Zn(2+) exhibited a highly selective and pronounced enhancement in the fluorescence emission among different cations by forming a 2:1 complex. The receptor can detect Zn(2+) up to nanomolar level (6.

"Turn-on" fluorescent dipodal chemosensor for nano-molar detection of Zn(2+): application in living cells imaging.

A malonohydrazide derivative bearing an imine and phenolic group was synthesized and had a high affinity and selectivity towards Zn(2+). The recognition properties of receptor 1 were evaluated using absorbance and fluorescence spectroscopy. The 1:1 stoichiometry of 1.

"Turn-on" fluorescent chemosensor for zinc(II) dipodal ratiometric receptor: application in live cell imaging.

A dipodal ligand 2,2'-((ethane-1,2-diylbis(azanediyl))bis(ethane-1,1-diyl))diphenol was synthesized through a condensation reaction and was characterized with IR, (1)H NMR, (13)C-NMR, and mass spectroscopy. The receptor 2 has shown marked enhancement in fluorescence intensity (emission signal at 341 nm) on binding with Zn(2+) as compared to other surveyed metal ions. The sensor has shown dramatic changes in dual channel fluorescence emission with λmax at 300 and 341 nm.