Design and Applications of Small Molecular Probes for Calcium Detection.

The physiological significance of calcium ions such as the role in cellular signalling, cell growth, etc. have driven the development of methods to detect and monitor the level of Ca ions, both in vivo and in vitro. Although various approaches for the detection of calcium ions have been reported, methods based on small molecular fluorescent probes have unique advantages including small probe size, easy monitoring of detection processes and applicability in biological systems.

Development of a supramolecular ensemble of an AIEE active hexaphenylbenzene derivative and Ag@Cu2O core-shell NPs: an efficient photocatalytic system for C-H activation.

A supramolecular ensemble having Ag@Cu2O core-shell nanoparticles stabilized by aggregates of a hexaphenylbenzene derivative has been developed which exhibits excellent photocatalytic efficiency in reactions involving preparation of imidazole and benzimidazole derivatives via C-H activation.

A bodipy based fluorescent probe for evaluating and identifying cancer, normal and apoptotic C6 cells on the basis of changes in intracellular viscosity.

The applications of a bodipy based probe 1 for the identification of diseased cell population out of normal cells on the basis of changes in intracellular viscosity have been explored. Probe 1 works on the principle of restriction of rotation in viscous medium and the molecular rotor nature of probe 1 is supported by low temperature H NMR and variable dihedral angle DFT and TD-DFT studies. More importantly, probe 1 is the first probe which shows its practical application in monitoring micro-viscosity changes in a cell based model system of undifferentiated, differentiated and apoptotic C6 glial cells.

Pentacenequinone-Stabilized Silver Nanoparticles: A Reusable Catalyst for the Diels-Alder [4 + 2] Cycloaddition Reactions.

Silver nanoparticles (AgNPs) stabilized by aggregates of derivative 4 have been used as catalyst for the construction of synthetically and biologically important [4 + 2] cycloadducts at room temperature.

A TICT based NIR-fluorescent probe for human serum albumin: a pre-clinical diagnosis in blood serum.

A TICT based NIR-fluorescent probe 3 has been designed and synthesized, which selectively detects HSA with fluorescence enhancement in blood plasma with a detection limit of 11 nM among the various proteins, nucleotides and thiols tested.

Aggregates of perylene bisimide stabilized superparamagnetic Fe3O4 nanoparticles: an efficient catalyst for the preparation of propargylamines and quinolines via C-H activation.

Aggregates of the perylene bisimide derivative act as reactors and stabilizers for the preparation of superparamagnetic Fe3O4 nanoparticles (NPs) which exhibit excellent catalytic efficiency in (i) A(3)-coupling and aldehyde free coupling reactions for the preparation of propargylamines and (ii) tandem intramolecular cyclization reaction for the synthesis of quinolines via C-H activation.

A hexaphenylbenzene based AIEE active two photon probe for the detection of hydrogen sulfide with tunable self-assembly in aqueous media and application in live cell imaging.

Supramolecular aggregates of hexaphenylbenzene derivative exhibit aggregation induced emission enhancement and modulation of self-assembled architecture from spherical to flower-like assembly in the presence of H2S. Furthermore, probe displays higher photostability, low toxicity and bright green fluorescence in two-photon microscopy (TPM) imaging for the detection of H2S in live HeLa cells.

Aggregates of the pentacenequinone derivative as reactors for the preparation of Ag@Cu2O core-shell NPs: an active photocatalyst for Suzuki and Suzuki type coupling reactions.

Aggregates of the pentacenequinone derivative 1 act as reactors and stabilizers for rapid and facile preparation of Ag@Cu2O core-shell nanoparticles (NPs) in aqueous medium. The in situ generated Ag@Cu2O core-shell hybrid materials enabled efficient visible light harvesting to catalyse the palladium free Suzuki-Miyaura and Suzuki type cross coupling reactions at room temperature.

A bodipy based dual functional probe for the detection of hydrogen sulfide and H2S induced apoptosis in cellular systems.

A bodipy based dual functional probe 1 has been designed and synthesized, which selectively detects H2S as well as monitors H2S induced apoptosis in cells.

AIEE active perylene bisimide supported mercury nanoparticles for synthesis of amides via aldoximes/ketoximes rearrangement.

Aggregates of perylene bisimide (PBI) derivative 3 serve as reactors and stabilizers for the preparation of mercury nanoparticles (HgNPs) which exhibit excellent catalytic efficiency in the conversion of aldoximes/ketoximes into primary/secondary amides via Beckmann rearrangement.

One-pot multicomponent synthesis of tetrahydropyridines promoted by luminescent ZnO nanoparticles supported by the aggregates of 6,6-dicyanopentafulvene.

Pot-shaped fluorescent aggregates of 6,6-dicyanopentafulvene derivative serve as reactors and stabilizers for the preparation of luminescent ZnO nanoparticles, which exhibit high catalytic efficiency in one-pot multicomponent synthesis of tetrahydropyridines.

A hexaphenylbenzene based AIEE active probe for the preparation of ferromagnetic α-Fe2O3 nanoparticles: facile synthesis and catalytic applications.

Fluorescent aggregates formed by self-assembly of a hexaphenylbenzene based derivative serve as a reactor and a stabilizer for the formation of ferromagnetic iron oxide (α-Fe2O3) nanoparticles in aqueous medium at room temperature. These α-Fe2O3 nanoparticles showed excellent catalytic activity in palladium, copper and amine free Sonogashira cross coupling reactions and also in photocatalytic degradation of rhodamine B dye.

A new thiacalix[4]arene-fluorescein based probe for detection of CN(-) and Cu(2+) ions and construction of a sequential logic circuit.

A new thiacalix[4]arene-fluorescein based fluorescent probe was synthesized, which shows a turn-on fluorescence response in the presence of CN(-) ions attributed to the nucleophilic addition of cyanide ions and the resulting cyanide adduct was used for the selective detection of copper ions. Furthermore, based on the fluorescence response a two input, one output, sequential logic circuit was constructed in the presence of CN(-) and Cu(2+) ions.

A highly selective fluorescent probe for hypochlorite and its endogenous imaging in living cells.

An oxime based fluorescent probe has been designed and synthesized, which detects free as well as enzymatically generated hypochlorite with a low detection limit and high sensitivity. In addition, the probe was successfully utilized for the monitoring of endogenously produced hypochlorite in LPS stimulated cell lines, C6 glioma and BV2 microglia.

Hexaphenylbenzene-based fluorescent aggregates for ratiometric detection of cyanide ions at nanomolar level: set-reset memorized sequential logic device.

A hexaphenylbenzene-based receptor 3 has been synthesized that forms a fluorescent spherical aggregate in mixed aqueous media due to its aggregation-induced emission enhancement attributes. These fluorescent spherical aggregates show ratiometric response toward cyanide ions via nucleophilic addition and undergo deaggregation to form smaller nanoaggregates. In addition, the solution-coated paper strips of 3 can detect cyanide ions in the range of ∼2.

Mercury assisted fluorescent supramolecular assembly of hexaphenylbenzene derivative for femtogram detection of picric acid.

Aggregates of hexaphenylbenzene derivatives 3, having pyrene groups form network of fluorescent nanofibres in presence of mercury ions. Further, fluorescent nanofibres of 3-Hg(2+) supramolecular ensemble exhibit sensitive and pronounced response towards the picric acid. In addition, the solution coated paper strips of 3-Hg(2+) supramolecular ensemble can detect picric acid in the range of 2.

Cyanide modulated fluorescent supramolecular assembly of a hexaphenylbenzene derivative for detection of trinitrotoluene at the attogram level.

Fluorescent nanorods formed by self-assembly of hexaphenylbenzene derivative in the presence of cyanide ions serve as a sensitive colorimetric and fluorogenic sensor for the detection of trinitrotoluene (TNT) at the attogram (10(-18) g) level with a detection limit of 10.21 ppq (parts per quadrillion).

A naphthalimide based chemosensor for Zn2+, pyrophosphate and H2O2: sequential logic operations at the molecular level.

A naphthalimide based fluorescent probe has been synthesized which shows ratiometric fluorescence response towards Zn(2+) ions and the in situ prepared -Zn(2+) complex was used for the detection of pyrophosphate and hydrogen peroxide which mimics the functions of sequential logic circuits at the molecular level.

A charge transfer amplified fluorescent Hg2+ complex for detection of picric acid and construction of logic functions.

A chemosensor 3 based on the N,N-dimethylaminocinnamaldehyde has been synthesized which shows fluorescence turn-on response with Hg(2+) ions, and the in situ prepared 3-Hg(2+) complex has been used for detection of picric acid via electrostatic interaction and construction of a combinatorial logic circuit with NOR and INHIBIT logic functions.

Thiacalix[4]crown based optical chemosensor for Fe3+, Li+ and cysteine: a Fe3+/Li+ ion synchronized allosteric regulation.

A heteroditopic chemosensor 2 based on a thiacalix[4]crown with a 1,3-alternate conformation has been synthesized and shows a selective fluorescence turn-off response with Fe(3+) ions in mixed aqueous media. Furthermore, the 2-Fe(3+) complex can be used as a chemosensing system for the detection of Li(+) and cysteine based on two different approaches. Moreover, the sequence addition of Fe(3+) and Li(+) triggers an Fe(3+)/Li(+) switchable on-off-on fluorescence chemosensor with negative allosteric regulations.

Ratiometric nanomolar detection of Cu2+ ions in mixed aqueous media: a Cu2+/Li+ ions switchable allosteric system based on thiacalix[4]crown.

A novel ditopic fluorescent chemosensor 2, based on the 1,3-alternate conformation of thiacalix[4]crown possessing two complexation sites, was synthesized and shows ratiometric nanomolar detection of Cu(2+) ions and exhibits negative allosteric behaviour between Cu(2+)/Li(+) ions in mixed aqueous media.

A charge transfer assisted fluorescent probe for selective detection of hydrogen peroxide among different reactive oxygen species.

A charge transfer assisted fluorescent probe is synthesized which undergoes a change in fluorescence emission at two different wavelengths in the presence of hydrogen peroxide.

Switching and fluorescence signal amplification with metal ions in allosteric systems based on 1, 3-alternate thiacalix[4]crown.

New thiacalix[4]crown derivatives 4 and 5 of 1,3-alternate conformation possessing anthracene and quinoline moieties respectively were synthesised and examined for their cation recognition abilities toward different cations by fluorescence spectroscopy. Selective optical recognition with fluorescence amplification was observed for Fe(3+)/K(+) and Hg(2+)/K(+) in chemosensors 4 and 5 respectively. Further it was observed that the formation of 4·Fe(3+) complex triggers the decomplexation of K(+) ion.

A Ni2+ selective chemosensor based on partial cone conformation of calix[4]arene.

Synthetic strategies are described to synthesize the calix[4]arene diamine 4 of partial cone (paco) conformation, which on condensation with 9-anthracene carbaldehyde forms the chemosensor 5 in paco conformation. The chemosensor 5 undergoes fluorescence enhancement in the presence of Ni(2+) ions.