Giant magnetoresistance (GMR) and ferromagnetic properties of DC and pulse electrodeposited Cu–Co alloys

Cu–Co ferromagnetic alloys occurring as granular films and exhibiting giant magnetoresistance (GMR) property have been synthesized using both DC and pulse electrodeposition techniques. The growth process of these electrodeposits comprising multiple granules of disparate morphology, magnetic features exhibits critical dependence on electrodeposition conditions. Using ferromagnetic resonance and magnetic hysteresis data, we have attempted a correlation between evolution of these electrodeposits and their ferromagnetic properties with special emphasis on GMR property.     

Rapid Validated RP-HPTLC Method for the Quantification of Major Bioactive Constituents of Crataegus oxyacantha L.

JPC – Journal of Planar Chromatography – Modern TLC - A reverse phase high-performance thin-layer chromatography (RPHPTLC) method was developed for determination of vitexin, hyperoside,...     

The inhibition of the mammalian DNA methyltransferase 3a (Dnmt3a) by dietary black tea and coffee polyphenols

Background  

Black tea is, second only to water, the most consumed beverage globally. Previously, the inhibition of DNA methyltransferase 1 was shown by dietary polyphenols and epi-gallocatechin gallate (EGCG), the main polyphenolic constituent of green tea, and 5-caffeoyl quinic acid, the main phenolic constituent of the green coffee bean.     

The potential of biomimetic nanofibrous electrospun scaffold comprising dual component for bone tissue engineering

Oils play a putative choice for alleviating various symptoms associated with bone-related disorders. In this present study, polyurethane (PU) scaffold encompassing with Mahua oil (MO) and propolis (PP) were developed using the electrospinning technique. Morphological analysis showed the reduction in the diameter of the electrospun scaffold with blending of MO and MO/PP into the PU matrix. The strong interactions between PU, MO, and PP were evident through the infrared spectrum and thermal analysis. The wettability results showed the hydrophobic nature in electrospun PU/MO scaffold and hydrophilic behavior in electrospun PU/MO/PP scaffold. Mechanical testing indicated the enhancement in the strength of the PU due to the addition of MO and PP. Moreover, the fabricated scaffolds exhibited nontoxicity, low hemoglobin release and improved blood clotting time as evident in the coagulation studies. The cell proliferation studies showed the enhanced fibroblast cell adhesion in the developed nanocomposites than the pristine PU. Hence, the fabricated PU scaffolds blended with MO and PP having desirable properties can serve as a valuable candidate for bone tissue repair.     

DNA interaction,free radical scavenging and in‐vitro antibacterial activity of drug‐based copper(II) complexes

The Cu(II) complexes of type [Cu(cpf)(Aⁿ)Cl] (Aⁿ = terpyridines, cpf = ciprofloxacin) were synthesized and characterized using IR, mass and reflectance spectra. The free ligands and their complexes were evaluated for their in‐vitro antimicrobial activity against a panel of Gram‐positive and Gram‐negative bacteria. The complexes exhibit better or equal inhibition in comparison to free fluoroquinolones. Binding interactions of the complexes with calf thymus (CT DNA) were investigated by absorption titration, viscosity studies and DNA melting temperature experiment. The cleavage reaction on pUC19 DNA was monitored by agarose gel electrophoresis. The lower concentration of the complexes was catalysed the dismutation of superoxide radical at biological pH, which indicates that the complexes can act as a possible model for superoxide dismutase. Copyright © 2011 John Wiley & Sons, Ltd.     

A promising class of luminescent derivatives of Silver(I) and Gold(I)-N-heterocyclic carbene

Starting from proligand 1-methyl-2-(phenyl)imidazo[1,5-a]pyridine-2-iumchloride ( 1 .HCl), 1-methyl-2-(phenyl)imidazo[1,5-a]pyridine silver(I)chloride, ( 2 ) has been prepared. Synthesis, structures and photophysical properties of (2,2^/−bipyridyl)-1-methyl-2-(phenyl)imidazo[1,5-a]pyridinesilver(I)hexaflurophosphate, ( 3 ), 1-methyl-2-(phenyl)imidazo[1,5-a]pyridinesilver(I)carbazolate, ( 4 ) and 1-methyl-2-(phenyl)imidazo[1,5-a]pyridinegold(I)carbazolate, ( 5 ) are focused. Herein we have first reported the NHC-Ag-(bpy/carbazole). All the complexes have been characterized by elemental analysis, various spectroscopic studies and finally screened for luminescent properties. All the complexes are strongly emissive. Solid state structures of 2 , 3 , 4 and 5 have been determined by X-ray diffraction studies. Conventionally, complex 2 adopts linear geometry whereas complex 3 embraces triangular planar geometry around Ag; complex 4 and 5 clinches linear geometry around Ag/Au. All the complexes absorb light within 275–343 nm. Complex 3 is luminous at ~407 mn, whereas complex 4 and 5 luminous at ~360 nm having short life time 1.00–6.97 ns. The quantum yield (Φ_em) of the complexes varies 0.106–0.186. It is expected variation of luminescence arises due to change of metal and the chromophore (bpy/carbazole). Density Functional Theory (DFT) and Temparature Dependent Density Functional Theory (TDDFT) calculations were performed to verify crystallographically derived parameters and to calculate the UV–Vis properties of the ground state as well as of the first excited state of the complexes.     

Anti-arthritic activity of Tin oxide-Chitosan-Polyethylene glycol carvacrol nanoparticles against Freund’s adjuvant induced arthritic rat model via the inhibition of cyclooxygenase‑2 and prostaglandin E2

Rheumatoid arthritis (RA) results in increased rate of mortality in millions of people worldwide. Research utilizing Tin oxide – Chitosan- Polyethylene glycol Carvacrol (SCP-CAR) nanocomposites has gained increased attention because of its multipotent properties and application in diverse fields including medicinal preparations. The aim of the investigation was to synthesize and to examine the anti-arthritic ability of SCP-CAR nanocomposites against CFA -induced RA in rats. Arthritis induction was done by injecting 0.1 ml of Complete Freund’s adjuvant (CFA) intradermally. Body weight, weight of organs, hind paw volumes and arthritis score was assessed and the levels of inflammatory modulators such as IL-6, IL-1β, IL-10, TNF-α, PGE2 and COX-2 was examined using assay kits. Lipid peroxidation status, antioxidant enzyme activities and levels of liver function enzymes were evaluated using standard procedures. Histopathological changes observed in hind limb of experimental animals were viewed under microscope using H& E staining. The SCP-CAR nanocomposites treated arthritic animals showed increased bodyweight and reduced hind paw volume, organ weight and arthritis score together with elevated antioxidants status and depleted proinflammatory cytokines. Histopathological observation also showed reduction in bone destruction and penetration of inflammatory cells following treatment with SCP-CAR nanocomposites. Thus, together the findings depict the anti-arthritic and anti-inflammatory potential of SCP-CAR nanocomposites suggesting that it could be used as potent therapeutic agent to treat animals against arthritis induced by CFA.     

Cubic Auto-Catalysis Reactions in Three-Dimensional Nanofluid Flow Considering Viscous and Joule Dissipations Under Thermal Jump

In this problem, simultaneous effects of Joule and viscous dissipationin three-dimensional flow of nanoliquid have been addressed in slip flow regime under timedependent rotational oscillations. Silver nanoparticles are submerged in the base fluid (water)due to their chemical and biological features. To increment the novelty, effects of cubicautocatalysis chemical reactions and radiative heat transfer have been incorporated in therelated boundary layer equations. Dimensionless partial differential system is solved byemploying the proposed implicit finite difference approach. Convergence conditions andstability criteria are obtained to ensure the convergence and accuracy of solutions.A comparative analysis is proposed for no-slip nanofluid flow (NSNF) and slip nanofluid flow(SNF). Variations in skin-friction coefficients, Sherwood and Nusselt numbers against physicalparameters are tabulated. It is investigated that velocity slip and temperature jump significantlycontrol drag forces and rate of heat transfer.     

Spectroscopic and electrochemical study for evaluating DNA interaction activity of 4‐(3‐halophenyl)‐6‐(pyridin‐2‐yl)pyrimidin‐2‐amine based piano stool Cp* Rh (III) and Ir (III) complexes

Six novel organometallic half sandwich complexes [(η5‐C₅Me₅)M(L^1–3)Cl]Cl.2H₂O were synthesized using [{(η⁵‐C₅Me₅)M(μ‐Cl)Cl₂], where M = Ir (III)/Rh (III) and L^1–3 = three pyridyl pyrimidine based ligands; and characterized by NMR, Infra‐red spectroscopy, conductance, elemental and thermal analysis. The complex‐DNA binding mode and/or strength evaluated using absorption titration, electrochemical studies and hydrodynamic measurement proposed intercalative binding mode, which was also confirmed by molecular docking study. Differential pulse voltammetry and cyclic voltammetry studies indicated an alteration in oxidation and reduction potentials of complexes (M⁺⁴/M⁺³) in presence of CT‐DNA. The metal complexes can cleave plasmid DNA as proposed in gel electrophoretic analysis. The LC₅₀ values of complexes evaluated on brine shrimp suggested their potent cytotoxic nature.