Targeting genomic DNAs and oligonucleotide on base specificity: A comparative spectroscopic, computational and in vitro study.

Drug discovery in targeted nucleic acid therapeutics encompass several stages and rigorous challenges owing to less specificity of the DNA binders and high failure rate in different stages of clinical trials. In this perspective, we report newly synthesized ethyl 4-(pyrrolo[1,2-a]quinolin-4-yl)benzoate (PQN) with minor groove A-T base pair binding selectivity and encouraging in cell results. This pyrrolo quinolin derivative has shown excellent groove binding ability with three of our inspected genomic DNAs (cpDNA 73 % AT, ctDNA58% AT and mlDNA 28 % AT) with varying A-T and G-C content.

Effect of ancillary ligand on DNA and protein interaction of the two Zn (II) and Co (III) complexes: experimental and theoretical study.

In the present work we have developed one mononuclear Zn(II) complex [Zn(L)(H2O)] (Complex 1) by utilizing a tetracoordinated ligand HL, formed by simple condensation of 2, 2 dimethyl 1,3 diamino propane and 3- ethoxy salicylaldehyde and one newly designed mononuclear Co (III) complex [Co(L)(L1)] (complex 2) by utilizing (HL) and 3- ethoxy salicylaldehyde(HL1) as an ancillary ligand. The newly developed complex have been spectroscopically characterized. An interesting phenomenon has been noticed that in presence of ancillary ligand, the solubility in buffer solution and the thermal stability of complex comparatively increases than .

Active Bromoaniline-Aldehyde Conjugate Systems and Their Complexes as Versatile Sensors of Multiple Cations with Logic Formulation and Efficient DNA/HSA-Binding Efficacy: Combined Experimental and Theoretical Approach.

Two fluorescence active bromoaniline-based Schiff base chemosensors, namely, ()-4-bromo-2-(((4-bromophenyl)imino)methyl)phenol ( ) and ()-2-(((4-bromophenyl)imino)methyl)phenol ( ), have been employed for the selective and notable detection of Cu and Zn ions, respectively, with the simultaneous formation of two new metal complexes [Cu(L)] and [Zn(L)] . X-ray single crystal analyses indicate that complexes and are tetra-coordinated systems with substantial CH..

Insights on the interaction of phenothiazinium dyes methylene blue and new methylene blue with synthetic duplex RNAs through spectroscopy and modeling.

The ubiquitous influence of double stranded RNAs in biological events makes them imperative to gather data based on specific binding procedure of small molecules to various RNA conformations. Particular interest may be attributed to situations wherein small molecules target RNAs altering their structures and causing functional modifications. The main focus of this study is to delve into the interactive pattern of two small molecule phenothiazinium dyes, methylene blue and new methylene blue, with three duplex RNA polynucleotides-poly(A).

Understanding the Effect of Single Cysteine Mutations on Gold Nanoclusters as Studied by Spectroscopy and Density Functional Theory Modeling.

Fluorescent metal nanoclusters have generated considerable excitement in nanobiotechnology, particularly in the applications of biolabeling, targeted delivery, and biological sensing. The present work is an experimental and computational study that aims to understand the effects of protein environment on the synthesis and electronic properties of gold nanoclusters. MPT63, a drug target of Mycobacterium tuberculosis, was used as the template protein to synthesize, for the first time, gold nanoclusters at a low micromolar concentration of the protein.

CB7 as a drug vehicle and controlled release of drug through non ionic surfactant: Spectroscopic technique.

A study of the comparative drug carrier properties of cucurbituril[7] (CB7) and β-cyclodextrin (β-CD) with a naphthalimide derivative, [2-(2-aminoethyl)-1H-benzo[deisoquinoline-1,3(2H)-dione] (NAP) and its release in aqueous solution using micellar environment, is the key research interest of this work. The profound changes in the different spectroscopic behavior have been attributed to the formation of a 1:1 inclusion complex for NAP:CB7 system. Several experimental outcomes clearly interpreted that CB7 has better drug carrier properties for NAP compared to β-CD.

Photoinduced Electron Transfer Switching Mechanism of a Naphthalimide Derivative with its Solvatochromic Behaviour: An Experimental and Theoretical Study with In Cell Investigations.

The sole existence of a t-bone-shaped naphthalimide derivative [2-(2-aminoethyl)-1H-benzo[de]isoquinoline-1,3(2H)dione] (NAP), which gives rise to a photoinduced electron transfer (PET) mechanism, has been established using a combination of experimental and theoretical studies. In parallel an in vitro-in cell PET mechanism has also been shown. To understand the photophysics of NAP, solvent studies have been carried out in different solvents.

Exploring the interaction of phenothiazinium dyes methylene blue, new methylene blue, azure A and azure B with tRNA: spectroscopic, thermodynamic, voltammetric and molecular modeling approach.

This study focuses on the understanding of the interaction of phenothiazinium dyes methylene blue (MB), new methylene blue (NMB), azure A (AZA) and azure B (AZB) with tRNA with particular emphasis on deciphering the mode and energetics of the binding. Strong intercalative binding to tRNA was observed for MB, NMB and AZB, bound by a partial intercalative mode. AZA has shown groove binding characteristics.

Aggregation-induced fabrication of fluorescent organic nanorings: selective biosensing of cysteine and application to molecular logic gate.

Self-aggregation behavior in aqueous medium of four naphthalimide derivatives has exhibited substitution-dependent, unusual, aggregation induced emission enhancement (AIEE) phenomena. Absorption, emission, and time-resolved study initially indicated the formation of J-type fluorescent organic nanoaggregates (FONs). Simultaneous applications of infrared spectroscopy, theoretical studies, and dynamic light scattering (DLS) measurements explored the underlying mechanism of such substitution-selective aggregation of a chloro-naphthalimide organic molecule.

Spectroscopic and quantum mechanical approach of solvatochromic immobilization: modulation of electronic structure and excited-state properties of 1,8-naphthalimide derivative.

Photophysical and spectroscopic properties of a fluorescent analogue, 2-(5-selenocyanato-pentyl)-6-chlorobenzo- [de]isoquinoline-1,3-dione (NP) in different solvents has been described in this paper using steady-state, time resolved spectroscopy and density functional theory (DFT) calculation. Stoke's shifted emission band in different solvents clearly demonstrate the highly polar character of the excited state, which is also supported by the enhancement of dipole moment of the molecule upon photoexcitation. Spectroscopic studies and multiple linear regression analysis method reveal that the solvatochromic behavior of the probe depends not only on the polarity of the medium but also on the hydrogen bonding interaction with the solvents.

An efficient, Schiff-base derivative for selective fluorescence sensing of Zn²⁺ ions: quantum chemical calculation appended by real sample application and cell imaging study.

Since zinc ions (Zn(2+)) are involved in numerous biological phenomena and go through subsequent interactions with zinc-binding proteins, we have attempted a sensitive fluorescence based detection of this second most abundant metal ion using an engineered and synthesized Schiff-base ligand, namely 2,4-bis((Z)-2-(1-(pyridin-2-yl)ethylidene)hydrazinyl)pyrimidine (PyHP). The ligand exhibits a zinc-induced fluorescence response when investigated in a MeOH-buffer (10 mM HEPES, pH = 7) (4 : 1) solvent mixture. The presence of zinc ions (λ(ex) = 410 nm, quantum yield, ϕ = 0.

Unveiling the groove binding mechanism of a biocompatible naphthalimide-based organoselenocyanate with calf thymus DNA: an "ex vivo" fluorescence imaging application appended by biophysical experiments and molecular docking simulations.

The present study embodies a detailed investigation of the binding modes of a potential anticancer and neuroprotective fluorescent drug, 2-(5-selenocyanato-pentyl)-6-chloro benzo[de]isoquinoline-1,3-dione (NPOS) with calf thymus DNA (ctDNA). Experimental results based on spectroscopy, isothermal calorimetry, electrochemistry aided with DNA-melting, and circular dichroism studies unambiguously established the formation of a groove binding network between the NPOS and ctDNA. Molecular docking analysis ascertained a hydrogen bonding mediated 'A-T rich region of B-DNA' as the preferential docking site for NPOS.

Self-aggregation of MEGA-9 (N-nonanoyl-N-methyl-D-glucamine) in aqueous medium: physicochemistry of interfacial and solution behaviors with special reference to formation energetics and micelle microenvironment.

Self-aggregation of MEGA-9 (N-nonanoyl-N-methyl-D-glucamine), a nonionic sugar-based surfactant, was studied with respect to the effect of salt (NaCl) and ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate) on its critical micelle concentration (cmc), aggregation number, hydrodynamic dimensions, energetics of micellization, and micellar microenvironment. Fluorimetry (both steady state and time resolved) was used to understand the microenvironments under the influence of additives. NaCl was found to decrease cmc, increase aggregation number (N), increase micellar size, and decrease enthalpy of micelle formation; the IL effect on the parameters was mostly opposite.

Explicit spectral response of the geometrical isomers of a bio-active pyrazoline derivative encapsulated in β-cyclodextrin nanocavity: a photophysical and quantum chemical analysis.

The existence of two geometrical isomers (cis- and trans-) of a biologically significant pyrazoline derivative [5-(-1'-(4-bromo-phenyl)-3a',7a'-hexahydro-1'H-indazol-3'-yl)-3-methyl-1-phenyl-1H-pyrazole-4-carbonitrile] (PZ) has been established using a combined theoretical and experimental investigation. Solvatochromic analysis of PZ revealed the existence of said cis- and trans- isomers. The unique solvatochromic response of the PZ isomers and their preferential encapsulation within β-cyclodextrin (β-CD) nanocavity clearly shows the difference in the behavioral nature of the isomers of PZ in homogeneous and heterogeneous medium.

Differential contribution of Igepal and CnTAB micelles on the photophysics of nonsteroidal drug Naproxen.

Spectroscopic studies of Naproxen (NP), a nonsteroidal drug have been carried out in well characterized, micellar media of cationic surfactants of a homologous series having general formula C(n)TAB (alkyl trimethyl ammonium bromide) and of nonionic surfactants of Igepal (Ig) series (poly(oxyethylene) nonyl phenol). The fluorescence behavior of the drug molecule in C(n)TAB micelles has been found to be opposite to that in Igepal micelles. The binding constants during probe micelle binding have been evaluated from relevant fluorescence data.