Seven new combinations in Phanera (Fabaceae: Caesalpinioideae: Cercideae)

Seven new combinations in Phanera Lour. are made for species which were either described in Lasiobema (Korth.) Miq. or later transferred to Lasiobema from Bauhinia L

Human peripheral blood mononuclear cells targeted multidimensional switch for selective detection of HSO3− anion

A new ratiometric π-conjugated luminophore with donor-acceptor (D- π- A) network CM {(E)-2-(4-(2-(9-butyl-9H-carbazol-3-yl)vinyl)benzylidine)malononitrile} has been synthesized by malononitrile conjugated carbazole dye with an intervening p-styryl spacer. Here, p-styryl conjugated malononitrile is used as a recognition site for the detection of HSO3− with a fast response time (within 50 s). In a mixed aqueous solution, CM reacts with HSO3− to give a new product 1-(9-butyl-9H-carbazol-3-yl)-2-(4-(2, 2-dicyanovinyl)phenyl)ethane-1-sulfonic acid. The probe exhibits positive solvatofluorochromism with solid state red fluorescence. The restriction of intermolecular rotation of p-styryl conjugated malononitrile unit enhances the typical solid state fluorescence properties. The probe (CM and its corresponding aldehyde CA) also demonstrates a strong solvent dependence yielding blue to green to pink and even red fluorescence in commonly used organic solvents like n-hexane, toluene, diethyl ether (DEE), THF, DCM, Dioxane, CH3CN and MeOH. The chemodosimetric approach of HSO3− selectively takes place at the olefinic carbon exhibiting a prominent chromogenic as well as ratiometric fluorescence change with a 147 nm blue-shift in the fluorescence spectrum. CM can detect HSO3− as low as 1.21 × 10−8 M. Moreover, the CM can be successfully applied to detect intrinsically generated intracellular HSO3− in human peripheral blood mononuclear cells (PBMCs). CM has shown sharp intensities (2628 ± 511.8) when the cells are HSO3− untreated. At green channel (at 486 nm) almost negligible fluorescence intensities are found (423 ± 127.5) for HSO3− untreated samples. However, the green fluorescence (2863 ± 427.5) increases significantly (p < 0.05), and simultaneously the red fluorescence gets significantly (p < 0.05) diminished (515 ± 113.2) after addition of HSO3−. The CM has been effectively utilized for evaluating the bisulfite ions in food samples as well. The concentrations of HSO3− in diluted sugar samples have been determined with the recovery of 97.6–9.12%

FRET based ratiometric switch for selective sensing of Al3+ with bio-imaging in human peripheral blood mononuclear cells

In this work, a triphenylamine and rhodamine-B (donor–acceptor) hybrid switch (TPRH) was rationally designed, synthesised and characterised as a novel fluorescence resonance energy transfer (FRET) ratiometric fluorescent chemosensor for specific sensing of Al3+ over other important metal ions in mixed aqueous solution. We proposed that the sensor in hand (TPRH) is non-toxic and can be successfully employed to detect the Al3+ ion in human peripheral blood mononuclear cells (PBMCs), showing intracellular ‘FRET-ON’ mechanism. The orientation of the probe was designed in such a way that the fluorescence (or Förster) resonance energy transfer (FRET) proceeded from the ‘donor moiety’ triphenylamine to the ‘accepter moiety’ rhodamine-B. This fluorescent probe was found to be highly selective towards Al3+ over other important guest metal ions, including Fe3+ and Cr3+. Considering the adverse effects of Al3+ ions on human health and also on the environment, the development of sensitive and specific tools for the detection of Al3+ ions is of great value. The limit of detection (LOD) of TPRH was found to be in the order of 10−8 M. The TPRH–Al3+ complex showed reversible binding with demetallation in the presence of EDTA. In accordance with this reversibility, the fluorescence output at 576 nm from two active chemical inputs, namely, Al3+ and EDTA, followed a truth table of an INHIBIT logic gate. Moreover, cytotoxic studies found that the probe was safe to use in a biological system with good cell membrane permeability. More importantly, the bio-imaging of living human peripheral blood mononuclear cells (PBMCs) showed that TPRH could be used as an effective fluorescent probe for a prominent ratiometric in vitro detection of the transition trivalent metal ion Al3+. We evidenced a significant (p < 0.05) shift from blue to red fluorescence when Al3+ was added to the cell suspension, thus proving TPRH as a good candidate to detect intracellular Al3+

Aggregation-induced emission switch showing high contrast mehanofluorochromism and solvatofluorochromism: Specifically detects HSO3− in bioimaging studies

In this work, a novel mechanoresponsive luminescent (MRL) and aggregation induced emission (AIE) switch, 2-(4-((9-butyl-9H-carbazol-3-yl)ethynyl)benzylidene)malononitrile (CABM) has been synthesized by a perfect blending of the carbazole-based triple bond and benzyl malononitrile conjugated derivative via the ‘sonogashira coupling reaction’. The optoelectronic properties of this donor–π–acceptor (D–π–A) framework spontaneously originates a prominent yellow fluorescence which further exhibits a mechanical stimuli induced orange – red emission. Interestingly, just after fumed with dichloromethane (DCM) vapor, the rubbed CABM powder facilely exhibits a restoration in the emission profile as well as fluorescence color. Moreover, this multidimensional switch, CABM shows a prominent solvent dependent sensitivity towards different polarities of organic solvents. CABM also exhibits a typical intramolecular charge transfer (ICT) mechanism along with AIE behaviors with high solid-state efficiency. Importantly, CABM acts as a fluorescence indicator for the qualitative and quantitative detection of low-level water content as impurity in organic solvent. CABM is also found to specifically sense HSO3− anion compared to other guest anions. These promising observations inspire us for the bioimaging studies by using human blood cells which clearly exhibit that CABM can be used to detect HSO3− in human peripheral blood mononuclear cells (PBMCs)

A new ratiometric switch “two-way” detects hydrazine and hypochlorite via a “dye-release” mechanism with a PBMC bioimaging study

A new ratiometric fluorescent probe (E)-2-(benzo[d]thiazol-2-yl)-3-(8-methoxyquinolin-2-yl)acrylonitrile (HQCN) was synthesised by the perfect blending of quinoline and a 2-benzothiazoleacetonitrile unit. In a mixed aqueous solution, HQCN reacts with hydrazine (N2H4) to give a new product 2-(hydrazonomethyl)-8-methoxyquinoline along with the liberation of the 2-benzothiazoleacetonitrile moiety. In contrast, the reaction of hypochlorite ions (OCl−) with the probe gives 8-methoxyquinoline-2-carbaldehyde. In both cases, the chemodosimetric approaches of hydrazine and hypochlorite selectively occur at the olefinic carbon but give two different products with two different outputs, as observed from the fluorescence study exhibiting signals at 455 nm and 500 nm for hydrazine and hypochlorite, respectively. A UV-vis spectroscopy study also depicts a distinct change in the spectrum of HQCN in the presence of hydrazine and hypochlorite. The hydrazinolysis of HQCN exhibits a prominent chromogenic as well as ratiometric fluorescence change with a 165 nm left-shift in the fluorescence spectrum. Similarly, the probe in hand (HQCN) can selectively detect hypochlorite in a ratiometric manner with a shift of 120 nm, as observed from the fluorescence emission spectra. HQCN can detect hydrazine and OCl− as low as 2.25 × 10−8 M and 3.46 × 10−8 M, respectively, as evaluated from the fluorescence experiments again. The excited state behaviour of the probe HQCN and the chemodosimetric products with hydrazine and hypochlorite are studied by the nanosecond time-resolved fluorescence technique. Computational studies (DFT and TDDFT) with the probe and the hydrazine and hypochlorite products were also performed. The observations made in the fluorescence imaging studies with human blood cells manifest that HQCN can be employed to monitor hydrazine and OCl− in human peripheral blood mononuclear cells (PBMCs). It is indeed a rare case that the single probe HQCN is found to be successfully able to detect hydrazine and hypochlorite in PBMCs, with two different outputs

Set of Multifunctional Azo Functionalized Semiconducting Cd(II)-MOFs Showing Photoswitching Property and Selective CO₂ Adsorption

Syntheses, structural characterizations, photoluminescence, and adsorption properties of three new azo-functionalized Cd­(II)-MOFs, namely, {[Cd­(azbpy)­(msuc)]·2.5­(H₂O)}_<i>n</i> (<b>2</b>), {[Cd­(azbpy)­(mglu)]·5­(H₂O)}_<i>n</i> (<b>3</b>), and {[Cd_1.5(azbpy)₂(glu)]·(NO₃)·MeOH}_<i>n</i> (<b>4</b>) [where msuc²⁻ = methylsuccinate; mglut²⁻ = methylglutarate; glut²⁻ = glutarate; azbpy = 4,4′-azobispyridine] have been reported. The compounds show different structures only with the variation of aliphatic dicarboxylates. The photoswitching behavior for the above-mentioned newly synthesized Cd­(II)-MOFs along with one of our previously reported other azo-functionalized Cd­(II)-MOF, namely, {[Cd­(azbpy)­(suc)]·2­(H₂O)}_<i>n</i> (<b>1</b>), has been studied extensively. At photoilluminated condition, the conductivity values can draw a clear structure–property relationship among the structures of compounds <b>1</b>–<b>4</b>. Single crystal structural analysis reveals that all the compounds exhibit a three-dimensional (3D) framework connected by azbpy linker and respective aliphatic dicarboxylate through their bis-chelating mono/bis oxo-bridging fashion. Compounds <b>1</b>–<b>3</b> exhibit an iso-structural honeycomb like 3D framework showing the same coordination environments, where the metal-carboxylate 2D sheets of compounds <b>1</b>–<b>3</b> are pillared by N,N′-donor azbpy linkers. On the other hand, compound <b>4</b> exhibits a 2-fold interpenetrated 3D framework with a little difference in its coordination environment and the pillaring of 1D metal-carboxylate ladder by azbpy linkers. All the compounds significantly demonstrate their enhanced sensitivity under light rather than the dark condition. The gas and solvent vapor sorption studies have been performed for the synthesized compounds <b>2</b>–<b>4</b>. Moreover, compound <b>2</b> exhibits an enhanced type IV selective CO₂ adsorption isotherm over N₂ along with the appearance of gate opening phenomena in that

Abstracts of 1st International Conference on Machine Intelligence and System Sciences

This book contains the abstracts of the papers presented at the International Conference on Machine Intelligence and System Sciences (MISS-2021) Organized by the Techno College of Engineering, Agartala, Tripura, India &amp; Tongmyong University, Busan, South Korea, held on 1–2 November 2021. This conference was intended to enable researchers to build connections between different digital technologies based on Machine Intelligence, Image Processing, and the Internet of Things (IoT). Conference Title: 1st International Conference on Machine Intelligence and System SciencesConference Acronym: MISS-2021Conference Date: 1–2 November 2021Conference Location: Techno College of Engineering Agartala, Tripura(w), IndiaConference Organizer: Techno College of Engineering, Agartala, Tripura, India &amp; Tongmyong University, Busan, South Korea