The ordered modular structure of a covalent organic framework (COF) facilitates the selective incorporation electronically active segments that can be tuned to function cooperatively. This designability inspires developing COF-based single-source white light emitters, required in next-generation solid-state lighting. Here, we present new anthracene-resorcinol-based COF exhibiting emission. keto-enol tautomers give rise dual emission, which by O-donor and N-donor solvents. Importantly, when...

Establishing the structure–property relationship for multi-stimuli responsive mechanochromic materials based on charge transfer luminogens.

The relative retardation of intramolecular charge transfer (ICT) and the solvation dynamics coumarin 152 in pure AOT, water, methanol, acetonitrile, formamide reverse micelles have been investigated using picosecond time-resolved emission spectroscopy. rate ICT has retarded almost 7 times at w0 = 4 32 compared to that water. is also observed methanol acetonitrile comparison acetonitrile. In time 12.22 ns, but water 7.27 ns. slow observed. much smaller several thousand fold decrease pool...

Abstract This article reports the p K a shift of an anti‐cancer drug, 20( S )‐camptothecin (CPT), upon encapsulation into nanocavity cucurbit[7]uril (CB7) macrocycle. Steady‐state, time‐resolved fluorescence and electrospray ionisation mass spectrometry (ESI‐MS) studies provide evidence for formation both 1:1 2:1 (CB7 ⋅ CPT) stoichiometries. Astonishingly, we have found that protonation CPT takes place at higher concentration macrocycle (≥50 μ M ) when stoichiometric complex develops....

Abstract Mechanistic details of DNA compaction is essential blue print for gene regulation in living organisms. Many vitro studies have been implemented using several agents. However, these compacting agents may some kinds cytotoxic effects to the cells. To minimize this aspect, research works had performed, but people never focused green solvent, i.e. room temperature ionic liquid as agent. best our knowledge, first ever report where we shown that guanidinium...

This research article explores the distinct TADF efficiency of three donor-acceptor based regio-isomers: DPAOCN (ortho-isomer), DPAMCN (meta-isomer), and DPAPCN (para-isomer). exhibits maximum in both solution solid-state with an impressive reverse inter-system crossing (RISC) rate ∼106 s-1; underlying cause being minimum singlet-triplet splitting energy or ΔEST SOC (spin-orbit coupling) between S1 & T1 states. Apart from TADF, differences crystal packing regio-isomers result intriguing bulk...

This work reports that ligand engineering can modulate the triplet harvesting mechanism in iodide-bridged rhombic Cu2I2 complexes. Complex-1, with a smaller Cu-Cu distance, exhibits phosphorescence from 3(M+X)LCT and 3CC states 66% quantum yield, whereas an increased distance complex-2 results switch of emission to TADF, which occurs via 1/3(M+X)LCT 83% yield. The TADF property has been utilized for fabrication pc-LED emitting efficient warm white light. Moreover, high charge-transfer nature...

Organic-inorganic hybrid metal halides have become enormously important in optoelectronics, sensing, photosensitization, etc. In this study, we report a structural transition from staircase configuration to cubane Cu(I) iodide-based polymers influenced by the coordination behavior of two different π*-acceptor ligands. The polymer structure, coordinated with 3-cyanopyridine, demonstrates efficient thermally activated delayed fluorescence (metal+halide)-to-ligand charge transfer [1/3(M+X)LCT]...

In this work, "isobutrin", an ecofriendly sensitizer that is extracted from Butea monosperma (commonly known as "Flame of the Forest") flowers, introduced. It a bright yellow pigment belonging to chalcone class and examined for optoelectronic applications. observed chelation dye with Ti ions results into strong dye-TiO2 charge transfer (DTCT) band in visible region. This Ti-Isobutrin chelate stable, irreversible its formation studied using Benesi–Hildebrand plot. The locations HOMO–LUMO...

Abstract Flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN) are derivatives of riboflavin (RF), a water‐soluble vitamin, more commonly known as vitamin B 2 . Flavins have attracted special attention in the last few years because recent discovery large number flavoproteins. In this work, these flavins used extrinsic fluorescence markers for probing microheterogeneous environment well‐known transport protein, human serum albumin (HSA). Steady‐state time‐resolved experiments...

In this study, the urea dynamics inside AOT reverse micelle (RM) has been monitored without intervention of water using time-resolved fluorescence techniques from picosecond to nanosecond time regime. It observed that is severely retarded compared RM due formation highly networked cluster RM. Time-resolved anisotropy study also confirms existence a confined environment around dye at higher concentrations micelle. The urea-water mixtures with increasing concentration get insight about effect...

Host–guest interactions between cucurbit[7]uril (CB7) and a cardiotonic drug, milrinone, have been explored using steady state pico-second time-resolved techniques. A novel fluorescence switch from ultraviolet (UV) to visible (cyan) is observed as consequence of upward pKa shift the drug inside nano-cavity cucurbit[7]uril.

Graphene oxide based molecular switching of ellipticine (E) has been utilized to probe its efficient loading onto graphene (GO) and subsequent release intra-cellular biomolecules like DNA/RNA. The green fluorescence E switches blue in GO back with polynucleotides. intensified emission the ellipticine-GO (E-GO) complex human serum albumin (HSA), a bluish upon addition dsDNA. Electron microscopy reveals formation distinctive 3D assemblies involving biomolecule(s) probably through non-covalent...

Herein, we have reported a new strategy for the synthesis of highly stable fluorescent copper nanoclusters (CuNCs) with l-cysteine (Cys) as protecting ligand within water nanopool reverse micelles (RMs). In present work, efforts are also given to address origin excitation-dependent fluorescence spectral shift CuNCs. From our experiments, elucidated that broad from CuNCs in RMs consists two spectrally overlapped bands corresponding metal-core and surface states The intrinsic emission...

The G-quadruplex (GQ-DNA), an alternative structure motif of DNA, has emerged as a novel and exciting target for anticancer drug discovery. GQ-DNA formed in the presence monovalent cations (Na(+)/K(+)) by human telomeric DNA is point interest due to their direct relevance cellular aging abnormal cell growths. Small molecules that selectively stabilize structures are considered be potential therapeutic agents. Herein, we probe proflavine (a well-known intercalator, hence acting...

The solvation dynamics of methanol and acetonitrile in n-heptane /AOT/ n-heptane/ AOT/acetonitrile reverse micelles have been investigated by picosecond time resolved emission spectroscopy using Coumarin 490 (C-490) as a probe. We observed substantially slower (order few ns) compared to pure solvents. is dependent on the w value (w = [polar solvent]/[AOT]) case but there little dependence micelles. different explained basis presence absence hydrogen bonding network.