A ferrocene-based chemo-dosimeter for colorimetric and electrochemical detection of cyanide and its estimation in cassava flour.

A simple chemo-dosimeter VDP2 bearing a ferrocene moiety was designed, synthesized, and characterized, and exhibited both chromogenic and electrochemical responses selectively for CN in HO-DMSO (9 : 1, v/v) medium. The probe VDP2 showed an instantaneous color change from colorless to yellow with CN that can readily be observed visually. The deprotonation of the benzimidazole -NH, followed by nucleophilic addition of CN to the olefinic C-atom, as evidenced by H and C NMR titration experiments, caused the colorimetric and electrochemical responses.

Spectroscopic and Theoretical Studies on the Selective Detection of Cyanide Ions by a Turn-On Fluorescent Chemo-Dosimeter and its Application in Living Cell Imaging.

A new chemo-dosimeter AK4 containing quinoline fluorophore has rationally been designed, synthesised and characterized using H and C NMR and mass spectral techniques. The probe senses explicitly CN ion through a dramatic enhancement in fluorescence over other commonly coexistent anions in HO:DMSO (9:1 v/v) medium over a broad pH range (4-10). H NMR titration revealed the deprotonation followed by nucleophilic addition reaction of CN, which was supported by C NMR and mass spectral examinations.

Multi-Spectroscopic and TD-DFT Studies on Chromogenic and Fluorogenic Detection of Cyanide in an Aqueous Solution.

Different spectroscopic techniques and Density Functional Theory (DFT)/Time-Dependent Density Functional Theory (TDDFT) calculations have been employed to investigate the dual channel CN detection behaviour of the developed chemo-dosimeter (AK3). The CN with AK3 reaction triggered a colour change from pale yellow to colourless and enhanced fluorescence. UV-Vis, fluorescence, H & C NMR and mass techniques coupled with theoretical calculations (Mulliken charges, dihedral angles) revealed that the CN sensing process mechanism involves deprotonation of the N-H group followed by nucleophilic addition reaction.

Insilico molecular modelling to identify PDK-1 targeting agents based on its protein-protein docking interaction.

PDK1, an attractive cancer target that downstreams 23 other kinases towards cell growth, survival and metabolism has gaining attention due to allosteric effect of ligands bound to it. Generally, the drug design strategy using pharmacophores is either a single protein structure or ensemble or ligand-based. Apart from these methods, yet another new approach of protein-protein docking with state of art computational tool like Schrodinger Suite to generate pharmacophores based on the interacting partners of the protein is proposed in this work.

Multi-spectroscopic, calorimetric and molecular dynamics evaluation on non-classical intercalation of antiviral drug Molnupiravir with DNA.

The interaction of an antiviral drug Molnupiravir () with calf thymus DNA (CT-DNA) was investigated using a series of biophysical techniques. A significant hyperchromism with a blue shift  nm in the UV-Vis spectra indicated a high binding affinity of for CT-DNA with binding constants in the order of 10 M. Competitive fluorescent dye displacement assays with ethidium bromide (EB) and Hoechst 33258 suggested an intercalative mode of binding of with CT-DNA.

Multi-spectroscopic, thermodynamic and molecular simulation studies on binding of pyrroloquinoline quinone with DNA: coexistence of intercalation and groove binding modes.

The interaction between enzyme-like pyrroloquinoline quinone () and calf-thymus DNA (CT-DNA) has been investigated by means of multi-spectroscopic (UV-Vis, fluorescence and circular dichroism), isothermal titration calorimetric (ITC), viscometry and molecular docking and metadynamics simulation techniques. Absorption spectral data suggested the formation of a /CT-DNA complex, which quenched the fluorescence of the dynamic quenching process. The results of CD spectral studies coupled with viscosity measurements, competitive binding assays with Hoechst 33258 and ethidium bromide (EB), KI quenching experiments, gel electrophoresis and DNA melting studies indicated groove binding mode of interaction of with CT-DNA.

Direct Adsorption of Graphene Oxide on a Glassy Carbon Electrode: An Investigation of Its Adsorption and Electrochemical Activity.

Different modes of attachment of graphene oxide (GO) on an electrode surface resulted in unusual catalytic behavior respective of attachment because of film thickness. The present work investigates the direct adsorption of GO to the surface of a glassy carbon (GC) electrode. Scanning electron microscopy images revealed that multilayers of GO get adsorbed on the GC substrate and the adsorption was limited by folding up of the GO sheets at their edges.

Spectroscopic and TD-DFT studies on the chromo-fluorogenic detection of cyanide ions in organic and aquo-organic media.

A new naked-eye chromogenic and fluorogenic probe KS5 has been developed for the detection of CN ions in neat DMSO and HO:DMSO (1:1 v/v) media. The probe KS5 exhibited selectivity towards CN and F ions in organic and high selectivity towards CN ions in aquo-organic media resulting in a colour change from brown to colourless and a turn-on fluorescence response. The probe could able to detect CN ions via a deprotonation process, which was conceived by consecutive addition of hydroxide and hydrogen ions and confirmed using H NMR studies.

Multi-spectroscopic and molecular simulation methods of analysis to explore the mode of binding of Mebendazole drug with calf-thymus DNA.

UV-vis, fluorescence, circular dichroism (CD) and H NMR spectroscopic techniques have been employed to explore the mode of binding of Mebendazole (MBZ) drug with calf thymus DNA (CT-DNA). UV-vis and fluorescence spectral studies suggested a complex formation between the drug and nucleic acid. The fluorescence of MBZ was found to enhance upon binding with CT-DNA through a ground state complex formation with K in the order of 10 M.

A highly selective probe for fluorometric sensing of cyanide in an aqueous solution and its application in quantitative determination and living cell imaging.

A simple fluorescent probe (KS4) containing multiple reaction sites (phenolic -OH, imine and C = C bonds) is successfully synthesized and characterized using H NMR, C NMR, mass and single crystal XRD techniques. KS4 exhibits high selectivity towards CN over a wide range of common anions in HO:DMSO (1:1 v/v) leading to an amazing turn-on fluorescence at 505 nm via deprotonation of the phenolic -OH group. The limit of detection (1.

Intercalation of anticancer drug Palbociclib with calf-thymus DNA: new insights from molecular spectroscopic, molecular dynamic simulations and cleavage studies.

The interaction between the anti-cancer drug Palbociclib () and calf-thymus DNA (CT-DNA) was investigated using various biophysical techniques in a physiological buffer (pH 7.4). It was found that intercalated into the base pairs of CT-DNA as evidenced from the results of UV-Vis, fluorescence, circular dichroism (CD), competitive binding assay with ethidium bromide (EB) and Hoechst 33258, KI quenching study, the effect of denaturing agent and viscosity measurements.

Intercalation of diafenthiuron insecticide with calf thymus DNA: spectroscopic and molecular dynamics analysis.

A series of biophysical experiments like UV-Vis, fluorescence, circular dichroism (CD), competitive displacement assays, voltammetric studies, viscosity measurements and denaturation effect and metadynamics simulation studies were performed to establish the mode of binding of diafenthiuron (DF) insecticide with calf thymus DNA (CT-DNA). Analysis of absorption and fluorescence spectra in Tris-HCl buffer of pH 7.4 indicates the formation of a complex between DF and CT-DNA and the binding constant of which is in the order of 10 M.

Multi-spectroscopic and free energy landscape analysis on the binding of antiviral drug remdesivir with calf thymus DNA.

Remdesivir (REM) is an antiviral drug, which exercises its effect by targeting specifically RNA-dependent RNA polymerase. The interaction of REM with calf thymus DNA (CT-DNA) was investigated by multi-spectroscopic techniques (UV-Vis, fluorescence, circular dichroism and P NMR) in combination with different biophysical experiments and metadynamics simulation studies. UV-Vis and fluorescence spectroscopic analysis indicated formation of a complex between REM and CT-DNA, whose binding constant is in the order of 10 M.

Molecular spectroscopic and molecular simulation studies on the interaction of oral contraceptive drug Ormeloxifene with CT-DNA.

The interaction between oral contraceptive drug Ormeloxifene (ORM) and calf thymus DNA (CT-DNA) was studied using UV-Vis, fluorescence, circular dichroism (CD) and H NMR spectral techniques under physiological buffer (pH 7.4). Competitive binding assays with ethidium bromide (EB) and Hoechst 33258, viscosity measurements, KI quenching studies, molecular docking and metadynamics simulation studies were also substantiated the spectroscopic results.

A closer look at the mode of binding of drug pemetrexed with CT-DNA.

The interaction of antifolate drug Pemetrexed () with CT-DNA has been studied by UV-Vis, fluorescence and circular dichroism spectroscopic techniques. The results of these spectroscopic studies in combination with viscosity measurements, voltammetric and KI quenching studies suggested a less-common mode of binding of with CT-DNA i.e.

Investigating binding of insecticide buprofezin to DNA by experimental and metadynamics simulation studies.

Buprofezin () is an insecticide which belongs to the thiadiazine structural family and known to damage DNA in mice. Though its toxic effect on human is not known clearly, understanding the mechanism of interaction of with DNA can prove useful when required. Multi-spectroscopic experiments such as UV-Vis, fluorescence, circular dichroism (CD) and H NMR coupled with viscosity measurements, urea effect and voltametric studies were performed to ascertain the mode of binding of with calf thymus DNA (CT-DNA).

Spectroscopic and theoretical evidences for the surface binding of voglibose drug with DNA.

Binding of voglibose (VOG), an alpha glucosidase inhibitor, with CT-DNA has been investigated using various spectroscopic techniques including UV-Vis, fluorescence and circular dichroism (CD) coupled with relative viscosity. Isothermal titration calorimetric studies have been used to calculate the thermodynamic parameters such as ΔH (0.0188 cal/mol), ΔS (63.

Concentration-dependent mode of binding of drug oxatomide with DNA: multi-spectroscopic, voltammetric and metadynamics simulation analysis.

The interaction between antihistaminic drug oxatomide () and calf-thymus DNA (CT-DNA) has been investigated in a physiological buffer (pH 7.4) using UV-Vis, fluorescence, H NMR and circular dichroism spectral techniques coupled with viscosity measurements, KI quenching, voltammetry and molecular modeling studies. binds with CT-DNA in a concentration-dependent manner.

Spectroscopic Studies on the Interaction of Naphthyridines with DNA and Fluorescent Detection of DNA in Agarose Gel.

Four new naphthyridine derivatives (R1-R4) possessing amino acid or boronic acid moieties have been synthesized and characterized using H and C NMR, FT-IR, and mass spectral techniques. The mechanism of binding of these probes with calf thymus DNA (CT-DNA) has been delineated through UV-Vis, fluorescence, and circular dichroism (CD) spectral techniques along with thermodynamic and molecular docking studies. Small hypochromicity in absorption maximum of the probes without any shift in wavelength of absorption suggests groove binding mode of interaction of these probes with CT-DNA, confirmed by CD and 1H NMR spectral data competitive binding assay with ethidium bromide (EB).

3-Hydroxy-2-naphthoic hydrazide as a probe for fluorescent detection of cyanide and aluminium ions in organic and aquo-organic media and its application in food and pharmaceutical samples.

The commercially available fluorophore, 3-hydroxy-2-naphthoic hydrazide (RS2), has rationally been selected for the study, which displays a rapid fluorescent response and high sensitivity for CN and Al(III) ions in neat DMSO and HO-DMSO (1:1 v/v) media. The addition of CN to RS2 triggers an enhancement in fluorescence at 505 nm (green fluorescence), while the addition of Al(III) increases the fluorescence of the probe with a blue-shift of emission maximum by 25 nm (bluish-green fluorescence). The probe's action was investigated by H NMR titrations that indicate deprotonation of OH and NH moieties by these ions.

2-Aminophenols based Schiff bases as fluorescent probes for selective detection of cyanide and aluminium ions - Effect of substituents.

Three Schiff base based probes are designed and synthesized by facile condensation of a commercially available fluorophore 2,6-diformyl-4-tert-butylphenol with 4-nitro-2-aminophenol (KP1), 2-aminophenol (KP2) and 4-tert-butyl-2-aminophenol (KP3) and are characterized using various spectral techniques. The probes exhibit high selectivity and sensitivity CN and Al(III) ions with striking fluorescent signaling responses in HO-DMSO (1:1, v/v) medium. The mechanism of the probes' detection of CN involves deprotonation of the phenolic OH group(s) followed by nucleophilic addition of CN onto imine C-atom.

A simple organic probe for ratiometric fluorescent detection of Zn(II), Cd(II) and Hg(II) ions in aqueous solution via varying emission colours to distinguish one another.

A bis (thiosemicarbazone) based probe has been synthesized and structurally characterized. The probe exhibits good selectivity towards Zn(II), Cd(II) and Hg(II) ions in an aqueous solution containing 95% water with ratiometric fluorescence changes. The modes of coordination of the probe with these metal ions and binding properties have been examined using different spectral techniques.

Multi-site probe for selective turn-on fluorescent detection of Al(III) in aqueous solution: synthesis, cation binding, mode of coordination, logic gate and cell imaging.

An easy to make organic probe (hereafter called as R) possessing multiple ligating sites have been synthesized and characterized using spectral techniques. The probe exhibits selective and sensitive turn-on fluorescence response with Al(III) in aqueous dimethylformamide (DMF) (1:1 v/v) solution. Fluorescence titration experiment shows that the probe binds with Al(III) with a 1:1 stoichiometry and a binding constant of 6.

Multi-spectroscopic, voltammetric and molecular docking studies on binding of anti-diabetic drug rosigiltazone with DNA.

The binding of an anti-diabetic drug rosiglitazone (RG) with calf-thymus DNA (CT-DNA) in physiological buffer (pH 7.4) has been investigated using various spectral techniques such as UV-Vis, fluorescence, H NMR and circular dichroism (CD) coupled with viscosity measurement and molecular docking studies. The binding of RG with CT-DNA results in small hypochromism without any change in absorption maximum and fluorescence quenching with hardly any shifts in emission maximum suggesting groove binding mode of interaction.