Correction: A highly sensitive triazole-based perfectly water soluble novel bis-Schiff base reversible fluorescent-colorimetric chemosensor for fast detection of Pb ions.

[This corrects the article DOI: 10.1039/D3RA06185J.].

Synthesis, Crystal Structure, DFT and Fluorescence Quenching Study of Novel syringe aldehyde-derived hydrazinyl-imidazole Based Schiff base Chemosensor.

In this study, we report a new syringe aldehyde-derived hydrazinyl-imidazole based fluorescent sensor (L) for sensitive detection of different inorganic quenchers (halide ions, bicarbonate ion, sulphide ion and transition metal ions). The chromophore (L) was obtained in good yield by the 1:1 condensation reaction of 2-hydrazino-4,5-dihydroimidazole hydrobromide and 4-hydroxy-3,5-dimethoxy benzaldehyde. L exhibited strong fluorescence in the visible region (around 380 nm) and its interaction with different quenchers was studied in details via fluorescence technique.

Organelle-targeting ratiometric fluorescent probes: design principles, detection mechanisms, bio-applications, and challenges.

Biological species, including reactive oxygen species (ROS), reactive sulfur species (RSS), reactive nitrogen species (RNS), F, Pd, Cu, Hg, and others, are crucial for the healthy functioning of cells in living organisms. However, their aberrant concentration can result in various serious diseases. Therefore, it is essential to monitor biological species in cellular organelles such as the cell membrane, mitochondria, lysosome, endoplasmic reticulum, Golgi apparatus, and nucleus.

A quinazolin-based Schiff-base chemosensor for colorimetric detection of Ni and Zn ions and '' fluorometric detection of Zn ion.

Herein, we have reported a novel quinazolin-based Schiff base chemosensor ()-2-benzamido-'-(1-(pyridin-2-yl)ethylidene)benzohydrazide (L). L has been designed, synthesised and characterised by H-NMR, IR spectroscopy, ESI-MS spectrometry and theoretical studies. The receptor showed appreciable colorimetric shift for both Ni and Zn ions and fluorometric "" response in presence of only Zn ion.

A novel dihydro phenylquinazolinone-based two-in-one colourimetric chemosensor for nickel(ii), copper(ii) and its copper complex for the fluorescent colourimetric nanomolar detection of the cyanide anion.

Currently, considerable efforts have been devoted to the detection and quantification of hazardous multi-analytes using a single probe. Herein, we have developed a simple, environment-friendly colourimetric sensor for the sensitive, selective and rapid detection of Ni and Cu ions using a simple organic Schiff base ligand L in methanol-Tris-HCl buffer (1 : 1 v/v, 10 mM, pH = 7.2).

Smartphone coupled with paper-based chemical sensor for on-site determination of iron(III) in environmental and biological samples.

We report a smartphone-paper-based sensor impregnated with cetyltrimethylammonium bromide modified silver nanoparticles (AgNPs/CTAB) for determination of Fe in water and blood plasma samples. The methodology for determination of Fe is based on the change in signal intensity of AgNPs/CTAB fabricated on a paper substrate after the deposition of analyte, using a smartphone followed by processing with ImageJ software. The mechanism of sensing for detection and determination of Fe is based on the discoloration of AgNPs which impregnated the paper substrate.

Triazole-based novel bis Schiff base colorimetric and fluorescent turn-on dual chemosensor for Cu and Pb: application to living cell imaging and molecular logic gates.

A triazole-based novel bis Schiff base colorimetric and fluorescent chemosensor (L) has been designed, synthesized and characterized by elemental analysis, H-NMR, ESI-MS, FTIR spectra and DFT studies. The receptor L showed selective and sensitive colorimetric sensing ability for Cu and Pb ions by changing color from colorless to yellow and light yellow respectively in CHOH-tris-buffer (1 : 1, v/v). However, it displayed strong fluorescence enhancement upon the addition of both Cu and Pb ions, attributed to the blocking of PET.

A novel hydrazide-based selective and sensitive optical chemosensor for the detection of Ni ions: applications in live cell imaging, molecular logic gates and smart phone-based analysis.

A novel flexible "N", "O"-rich hydrazide-based Schiff base chemoreceptor, 2-(benzamido)-N'-((pyridin-2-yl)methylene)benzohydrazide (L), was designed, synthesised and characterised viaH-NMR, IR spectroscopy, ESI-MS spectrometry and single-crystal XRD analysis. The receptor showed a colorimetric and fluorometric "turn on" response in the presence of only Ni ions in methanol-Tris-HCl buffer medium (10 mM, pH 7.2, 1 : 1 v/v).

A dual-mode highly selective and sensitive Schiff base chemosensor for fluorescent colorimetric detection of Ni and colorimetric detection of Cu.

In this paper, a novel flexible Schiff base chemosensor N'-(2-hydroxy-3-methoxybenzylidene)-2-(benzamido)benzohydrazide (L) has been designed, synthesised and characterised by 1H-NMR, IR spectroscopy, ESI-MS spectrometry and single crystal XRD analysis. A significant fluorescence enhancement of L was observed only in the presence of Ni2+ ions with a detection limit of 3.64 μM whereas Cu2+ induced fluorescence quenching, although both the metals showed colorimetric responses in methanol-Tris-HCl buffer (10 mM, pH 7.

A dipodal molecular probe for naked eye detection of trivalent cations (Al, Feand Cr) in aqueous medium and its applications in real sample analysis and molecular logic gates.

A simple and low cost multifunctional colorimetric receptor L has been designed, synthesized and characterized by H-NMR, IR spectroscopy, ESI-MS spectrometry and elemental analysis. The chemosensor L can selectively detect three biologically and environmentally important trivalent metal ions (Al, Feand Cr) both visually and spectrophotometrically in CHCN-HO (1 : 1, v/v) solution in the presence of other biologically relevant metal ions. The Job's plot analyses indicate the 2 : 2 binding stereochemistry for Al, Fe and Cr ions with L, which was further confirmed by H-NMR and ESI-MS studies.

Solvent-dependent fluorescent-colorimetric probe for dual monitoring of Al(3+) and Cu(2+) in aqueous solution: an application to bio-imaging.

A novel, quinoline-based smart probe L has been designed for the detection of Al(3+) and Cu(2+) at physiological range. The unprecedented solvent-dependent sensitivities of the probe L for simultaneous detection of Al(3+) and Cu(2+) ions with high selectivity and sensitivity have been observed for the first time. It displays quick responses through visible colorimetric as well as fluorogenic changes towards both Al(3+) and Cu(2+), as delineated by absorption and fluorescence titrations.

A reversible fluorescent-colorimetric imino-pyridyl bis-Schiff base sensor for expeditious detection of Al(3+) and HSO3(-) in aqueous media.

A reversible fluorescent-colorimetric imino-pyridyl bis-Schiff base receptor (N(1)E,N(4)E)-N(1),N(4)-bis(pyridine-4-ylmethylene)benzene-1,4-diamine for the detection of both Al(3+) and HSO3(-) in aqueous medium has been developed. Receptor exhibits an excellent selective fluorescent-colorimetric response toward Al(3+). The sensitivity of the fluorescent based assay (0.

catena-Poly[[(triphenyl-phosphane)copper(I)]-di-μ-iodido-[(triphenyl-phosphane)copper(I)]-μ-{1,2-bis-[1-(pyridin-4-yl)ethyl-idene]hydrazine}].

In the title coordination polymer, [Cu(2)I(2)(C(14)H(14)N(4))(C(18)H(15)P)(2)](n), the Cu(I) atom is coordinated by two I atoms, one P atom and one N atom in a fairly regular tetra-hedral arrangement. A crystallographic inversion centre generates a Cu(2)I(2) diamond with a Cu-Cu separation of 3.0120 (5) Å.

Mono- and dinuclear manganese(III) complexes showing efficient catechol oxidase activity: syntheses, characterization and spectroscopic studies.

Four side-off compartmental ligands L1-L4 [L1 = N,N'-ethylenebis(3-formyl-5-methyl-salicylaldimine), L2 = N,N'-1-methylethylenebis(3-formyl-5-methylsalicylaldimine), L3 = N,N'-1,1-dimethylethylenebis(3-formyl-5-methylsalicylaldimine) and L4= N,N'-cyclohexenebis(3-formyl-5-methylsalicylaldimine)] having two binding sites, N2O2 and O4, have been chosen to synthesize mononuclear and dinuclear manganese(III) complexes with the aim to study their catecholase activity using 3,5-di-tert-butylcatechol (3,5-DTBC) as substrate in the presence of molecular oxygen. In all cases only mononuclear manganese complexes (1-4) were obtained, with manganese coordination taking place at the N2O2 binding site only, irrespective of the amount of manganese salt used. All these complexes have been characterized by routine physico-chemical techniques.

Octahedral monodithiolene complexes of iron: characterization of S,S'-coordinated dithiolate(1-) pi radical monoanions: a spectroscopic and density functional theoretical investigation.

The reaction of cis-[Fe(III)(cyclam)Cl(2)]Cl with 1 equiv of sodium N-diethyldithiocarbamate, toluene-3,4-dithiolate, and maleonitriledithiolate in methanol in the presence of triethylamine afforded the cations [Fe(III)(cyclam)(Et(2)dtc)](2+) (1), [Fe(III)(cyclam)(tdt)](+) (2), and [Fe(III)(cyclam)(mnt)](+) (3), which were isolated as triflate, hexafluorophosphate, and tetrafluoroborate salt, respectively, using sodium triflate, potassium hexafluorophosphate, or sodium tetrafluoroborate as the source for the counteranion. Complexes 1, 2, and 3 possess an S = (1)/(2) ground state (low-spin ferric d(5)). These salts were characterized by X-ray crystallography, UV-vis, Mössbauer, and electron paramagnetic resonance spectroscopies.

1,2-Diphenyl-2-[4-(4-pyridyl)benzyl-idene-hydrazono]ethan-1-one.

In the title compound, C(26)H(19)N(3)O, the dimethyl-ene hydrazine (-C=N-N=C-) unit is approximately planar, the torsion angle around the N-N bond being 162.2 (6)°. The phenyl and benzoyl-phenyl rings at one end of the hydrazine unit are aligned at angles of 9.

Benzil bis-(ketazine).

1,1',2,2'-tetra-phenyl-2,2'-azinodiethanone), C(28)H(20)N(2)O(2), was obtained by the reaction of benzil monohydrazone with chromium(III) nitrate. The dibenzyl-idene hydrazine unit is nearly planar (r.m.

N,N'-Bis(4-pyridylmethyl-ene)octane-1,8-diamine.

The complete molecule of the title compound, C(20)H(26)N(4), is generated by a crystallographic centre of inversion and the central eight-carbon chain adopts a fully extended conformation. In the crystal, the molecules pack in layers parallel to (010).

Metal binding to bipyridine-modified PNA.

Substitution of natural nucleobases in PNA oligomers with ligands is a strategy for directing metal ion incorporation to specific locations within a PNA duplex. In this study, we have synthesized PNA oligomers that contain up to three adjacent bipyridine ligands and examined the interaction with Ni2+ and Cu2+ of these oligomers and of duplexes formed from them. Variable-temperature UV spectroscopy showed that duplexes containing one terminal pair of bipyridine ligands are more stable upon metal binding than their nonmodified counterparts.

Influence of metal coordination on the mismatch tolerance of ligand-modified PNA duplexes.

Recent studies on metal incorporation in ligand-modified nucleic acids have focused on the effect of metal coordination on the stability of metal-containing duplexes or triplexes and on the metal binding selectivity but did not address the effect of the sequence of the nucleic acid in which the ligands are incorporated. We have introduced 8-hydroxyquinoline Q in 10-mer PNA strands with various sequences and have investigated the properties of the duplexes formed from these strands upon binding of Cu(2+). Variable-temperature UV-vis spectroscopy shows that, in the presence of Cu(2+), duplexes are formed even from ligand-modified Q-PNA strands that have a large number of mismatches.

Crystal engineering of metalloporphyrin assemblies. New supramolecular architectures mediated by bipyridyl ligands.

Targeted synthesis of new supramolecular motifs of metalloporphyrins in crystals by a concerted mechanism of molecular recognition in three dimensions, aided by organic ligands, is presented; it involves induced assembly of [tetrakis(4-hydroxyphenyl)porphyrinato]zinc species by a combination of axial coordination through bridging bipyridyls and of lateral hydrogen bonding.

Hydrogen-bonded supramolecular lattice of the 1:3:4 complex between [5,10,15,20-meso-tetrakis(4-hydroxyphenyl)porphyrinato-kappa(4)N]zinc(II), dibenzo-24-crown-8 and methanol.

The title compound, [5,10,15,20-meso-tetrakis(4-hydroxyphenyl)porphyrinato-kappa(4)N]zinc(II) tris(dibenzo-24-crown-8) methanol tetrasolvate, [Zn(C(44)H(28)N(4)O(4))].3C(24)H(32)O(8).4CH(4)O, was synthesized and its molecular structure precisely characterized by low-temperature single-crystal analysis.