Gold Nanoparticles Supported on Magnesium Oxide Nanorods for Oxidation of Alcohols.

Gold nanoparticles supported on magnesium oxide nanorods (Au-MgO) have been synthesised by a solution based chemical reduction method. Au-MgO nanorods were found to be an efficient heterogeneous catalyst for oxidation of alcohols with hydrogen peroxide in aqueous medium at room temperature. To find out the best reaction conditions for oxidation, optimization of catalyst quantity, solvent, mole equivalence of hydrogen peroxide were carried out. The scope of the reaction was extended to several aromatic and aliphatic alcohols, product yields were quantified by gas chromatography (GC) and GC/mass spectroscopy. Heterogeneity and reusability tests were performed. The use of water as a solvent and hydrogen peroxide as co-catalyst at room temperature makes the reaction interesting from sustainable development point of view.

Recyclable Mesoporous Ceria Supported Gold Nanoparticles Based Catalyst for O-Arylation of Phenols.

Ceria supported gold nanoparticles (Au-CeO2 NPs) were prepared by a simple deposition-precipitation method. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR) and Raman analysis indicated the formation of gold nanoparticles over phase pure cerianite ceria support. The presence of gold nanoparticles was well identified by UV-DRS study. In addition, the field emission scanning electron microscope (FESEM) and high resolution transmission electron microscope (HR-TEM) images revealed that the maximum number of particles having spherical shape were approximately 10 nm size. Subsequently, surface area of the catalyst determined from BET, Langmuir and DFT methods were found to be 83.1, 134 and 85.2 m2 g(-1) respectively. N2 absorption-desorption measurement revealed that Au-CeO2 NPs was mesoporous in nature. Au-CeO2 NPs proved to be an efficient catalyst for the O-arylation reactions. The reaction conditions were optimized using 2,6-dimethoxyphenol and 1-chloro-4-nitrobenzene as a model substrate by changing the solvent, base, quantity of catalyst, and temperature. The scope of the work was extended to various substituted phenols and aryl halides (F, Cl and Br) and reusability of catalyst was tested for four cycles which showed no loss in its activity.

DMSO containing ruthenium(ii) hydrazone complexes: in vitro evaluation of biomolecular interaction and anticancer activity.

Synthesis, spectral, electrochemical and single crystal X-ray diffraction data of a new series of DMSO containing bivalent ruthenium hydrazone complexes are presented. XRD data of two of the new complexes revealed an octahedral coordination around the ruthenium ion satisfied by NOS2Cl2 atoms. Electrochemical studies showed the metal centred, quasi-reversible, one-electron redox behaviour of the new complexes. The binding of these complexes with biomolecules such as calf thymus DNA (CT-DNA) and bovine serum albumin (BSA) protein investigated by different spectrophotometric methods revealed an intercalative mode of interaction. The in vitro cytotoxicity of these complexes evaluated by the MTT assay on a panel of cancer and normal cell lines indicated that the above complexes are more toxic to cancer cells with a few micromolar concentrations as the IC50 value, but are significantly less toxic to normal cell lines. The observed variations in the binding interactions and cytotoxicity of the complexes were attributed to the nature of the hydrazide moiety of the hydrazones that influences their biological activities.

Effect of sintering temperature on structural and optical properties of indium(III) oxide nanoparticles prepared with Triton X-100 by hydrothermal method.

Indium(III) hydroxide (In(OH)3) powders prepared via Triton X-100 mediated hydrothermal method was sintered at different temperatures (400, 500 and 600°C) to yield indium(III) oxide nanoparticles (In2O3 NPs). Thermal studies of In(OH)3 confirmed complete conversion to In2O3 around 400°C. Powder X-ray diffraction (XRD) pattern of sintered In2O3 nanoparticles revealed the formation of phase pure cubic In2O3. The crystallite size of In2O3 NPs was increased from 12 to 26nm upon increasing the sintering temperature from 400°C to 600°C, while the percentage crystallinity was increased up to 90% after sintering at 600°C. A red shift in the band gap energy was observed with increasing sintering temperature due to the larger size of sintered In2O3 NPs. Room temperature photoluminescence spectra of the indium oxide nanoparticles showed both near band and excitonic emission of In2O3 due to oxygen vacancies.

Expression of the transmembrane mucins, MUC1, MUC4 and MUC16, in normal endometrium and in endometriosis.

STUDY QUESTION: Are the transmembrane mucins, MUC1, MUC4 and MUC16, differentially expressed in endometriosis compared with normal endometrium? SUMMARY ANSWER: This study revealed that transmembrane mucin expression does not vary significantly in normal endometrium during the menstrual cycle and is not altered in endometriosis relative to the epithelial marker, cytokeratin-18 (KRT18). WHAT IS KNOWN ALREADY: Increased serum levels of the transmembrane mucin fragments MUC1, MUC4 and MUC16 that normally dominate the apical surface of simple epithelia are found in several pathological conditions, including endometriosis. Altered mucin expression in gynecologic diseases may promote infertility or endometrial pathologies. STUDY DESIGN, SIZE, DURATION: This was a laboratory-based study of samples from 12 endometriosis patients as well as non-endometriosis control samples obtained from 31 patients. PARTICIPANTS/MATERIALS, SETTING, METHODS: Total RNA was isolated from endometrial biopsies of ectopic and eutopic endometrium from women with endometriosis and control patients from different stages of the menstrual cycle. Quantitative (q)-RT-PCR analyses were performed for the mucins, MUC1, MUC4 and MUC16, relative to the epithelial marker, cytokeratin-18 (KRT18), or ß-actin (ACTB). Frozen sections from endometrial biopsies of proliferative and mid-secretory stage women with endometriosis were immunostained for MUC1, MUC4 and MUC16. MAIN RESULTS AND THE ROLE OF CHANCE: qRT-PCR analyses of MUC1 and MUC16 mRNA revealed that these mucins do not vary significantly during the menstrual cycle nor are they altered in women with endometriosis relative to the epithelial marker, KRT18. MUC4 mRNA is expressed at very low levels relative to MUC1 and MUC16 under all conditions. There was little difference in MUC1 and MUC16 expression between eutopic endometrial and ectopic endometriotic tissues. MUC4 expression also was not significantly higher in the ectopic endometriotic tissues. Immunostaining for all three mucins reveals robust expression of MUC1 and MUC16 at the apical surfaces of endometrial epithelia, but little to no staining for MUC4. LIMITATIONS, REASONS FOR CAUTION: qRT-PCR analysis was the main method used for mucin detection. Additional studies with stage III-IV endometriotic tissue would be useful to determine if changes in MUC1 and MUC16 expression occur, or if MUC4 expression increases, at later stages of endometriosis. WIDER IMPLICATIONS OF THE FINDINGS: We report a comprehensive comparative profile of the major transmembrane mucins, MUC1, MUC4 and MUC16, relative to the epithelial marker, KRT18, in normal cycling endometrium and in endometriosis, and indicate constitutive expression. Previous studies have profiled the expression of individual mucins relative to ß-actin and indicate accumulation in the luteal phase. Thus, these differences in interpretation appear to reflect the increased epithelial content of endometrium during the luteal phase. STUDY FUNDING: This study was supported by: NIH R01HD29963 to D.D.C.; NIH U54HD007495 to S.M.H.; and NIH R01HD067721 to S.L.Y. and B.A.L. The authors have no competing interests to declare.

Photodegradation of 4-nitrophenol using cadmium sulphide nanoparticles.

An efficient method to degrade 4-nitrophenol (4-NP) using cadmium sulphide nanoparticles (CdS NPs) prepared by a novel method as a photocatalyst in the presence of H2O2 as a free radical generator was developed. To investigate the degradation mechanism, the interaction between the substrate (4-NP) and the catalyst (CdS NPs) was studied using UV-visible absorption and emission spectral techniques. Investigation on the effect of pH of the medium on the degradability of 4-NP revealed that neither the acidic (pH 4) nor alkaline (pH 9) is as suitable as pH 6 due to the desorption of 4-NP from the catalyst surface at the former condition and the existence of 4-NP in its most stable quinonoid form at the latter pH. Similarly, the effect of ratio between the photocatalyst (CdS NPs) and the substrate (4-NP) was also investigated to achieve higher efficiency in the photocatalytic reaction.

Binuclear copper complexes: synthesis, X-ray structure and interaction study with nucleotide/protein by in vitro biochemical and electrochemical analysis.

Two new, binuclear copper(II) hydrazone complexes have been synthesized and characterized by various physico-chemical techniques including single crystal X-ray diffraction. Interaction of these complexes with nucleotide and protein were analyzed by in vitro biochemical and electrochemical analysis. Both the complexes exhibited intercalative mode of binding with DNA. Further, gel electrophoresis assay demonstrated the ability of the complexes to cleave the supercoiled pBR322 plasmid DNA to nicked circular DNA form. Cytotoxicity of the complexes performed against a panel of cancer cell lines and a normal cell line proved that these complexes are potentially cytotoxic against the cancerous cell lines, particularly with IC50 as low as 0.7 µM against HeLa cell line.

Mesoporous nickel-aluminosilicate nanocomposite: a solid acid catalyst for ether synthesis.

Mesoporous nickel aluminosilicate, a solid acid catalyst prepared by sol-gel technique was utilized as a heterogeneous catalyst for the synthesis of symmetrical ethers by dehydro-condensation of alcohols. The prepared catalysts were characterized by Fourier-transform infra red spectroscopy (FT-IR), powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), N2 adsorption-desorption analysis, temperature programmed desorption of ammonia (TPD) and X-ray photoelectron spectroscopic techniques. The presence of the catalyst assisted the etherification reaction in 30 minutes. Ethers formed in these reactions were quantified by gas chromatography (GC) and the identities of few of them were confirmed by nuclear magnetic resonance spectral data (NMR).

UV-visible spectroscopic estimation of photodegradation of rhodamine-B dye using tin(IV) oxide nanoparticles.

Nanocrystalline, tin(IV) oxide (SnO(2)) particles has been prepared by thermal decomposition of tin oxalate precursor obtained from the reactions of tin(IV) chloride and sodium oxalate using eggshell membrane (ESM). The as-prepared SnO(2) nanoparticles were characterized by thermal studies, transmission electron microscopy (TEM), powder X-ray diffraction (XRD), Raman, FT-IR and UV-visible studies and used as a photocatalyst for the degradation of rhodamine-B (Rh-B) dye. The size of the prepared nanoparticles was in the range of 5-12nm as identified from the TEM images. Powder XRD data revealed the presence of a tetragonal, rutile crystalline phase of the tin(IV) oxide nanoparticles. Thermal analysis showed that the decomposition of tin oxalate precursor to yield the titled tin(IV) oxide nanoparticles was completed below 500°C. The extent of degradation of Rh-B in the presence of SnO(2) monitored by absorption spectral measurements demonstrated that 94.48% of the selected dye was degraded upon irradiation with UV light for 60 min.

Evaluation of DNA binding, DNA cleavage, protein binding and in vitro cytotoxic activities of bivalent transition metal hydrazone complexes.

Divalent Co, Ni and Cu hydrazone complexes containing [N'-(phenyl(pyridine-2-yl)methylidene) benzohydrazide] ligand were synthesised and characterised. Interactions of these complexes with DNA revealed an intercalative mode of binding between them. Further, all the hydrazone chelates showed moderate ability to cleave pUC19 DNA. Synchronous fluorescence spectra proved that the interaction of metal complexes with bovine serum albumin (BSA) resulted in a conformational change of the latter. Assay on the cytotoxicity of the above complexes against HeLa tumor cells and NIH 3T3 normal cells revealed that the complexes are toxic only against tumor cells but not to normal cells. In all the biological assays, the complex with copper ion as the metal center showed enhanced activities than the other two.

Spectroscopic investigations on the photodegradation of toluidine blue dye using cadmium sulphide nanoparticles prepared by a novel method.

A novel method to prepare cadmium sulphide nanoparticles (CdS NPs) possessing nearly uniform size was adopted using eggshell membrane (ESM), under different pH conditions. Significant yield of CdS NPs with smallest possible size was obtained by increasing the pH of the reaction medium from acidic to alkaline. The above prepared CdS NPs have been characterized by UV-vis absorption as well as emission spectra, powder X-ray diffraction, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The efficiency of the above prepared CdS NPs as a catalyst for the photodegradation of toluidine blue (TB) dye, as a function of pH as well as the ratio between the catalyst and the substrate was studied after irradiation with UV light. The results showed that an efficient interaction took place between the catalyst and the substrate to cause degradation of the selected dye. A maximum degradation of toluidine blue dye (90%) was observed at pH 8 which is higher than that of the efficiencies at pH 4 and pH 6.

Preparation, spectroscopy, EXAFS, electrochemistry and pharmacology of new ruthenium(II) carbonyl complexes containing ferrocenylthiosemicarbazone and triphenylphosphine/arsine.

A new series of new hetero-bimetallic complexes containing iron and ruthenium of the general formula [RuCl(CO)(B)(EPh3)(L)] (where E=P or As; B=PPh3, AsPh3, py or pip; L=ferrocene derived monobasic bidentate thiosemicarbazone ligand) have been synthesized by the reaction between ferrocene-derived thiosemicarbazones and ruthenium(II) complexes of the type [RuHCl(CO)(B)(EPh3)2] (where E=P or As; B=PPh3, AsPh3, py or pip). The new complexes have been characterized by elemental analyses, IR, electronic, NMR (1H, 13C and 31P), EXAFS (extended X-ray absorption fine structure spectroscopy) and cyclic voltammetric techniques. Antibacterial activity of the new complexes has been screened against Escherichia coli, Vibrio cholerae, and Pseudomonas aeruginosa species.

Studies on the synthesis, spectra, catalytic and antibacterial activities of binuclear ruthenium(II) complexes.

A new series of stable binuclear ruthenium(II) carbonyl complexes of the general formula [{RuX(CO)(EPh(3))(2)}(2)L] (where X=H or Cl; E=P or As and L=dibasic tetradentate diacetyl resorcinol (H(2)-DAR)) have been synthesised by reacting ruthenium(II) starting complexes [RuHX(CO)(EPh(3))(3)] (where X=H or Cl; E=P or As) and 4,6-diacetylresorcinol (H(2)-DAR) ligand in benzene medium. The structure of the new binuclear ruthenium(II) carbonyl complexes was established using elemental analysis, spectra (FT-IR, UV-vis and (1)H NMR), electrochemical and thermal studies. In these reactions, the 4,6-diacetylresorcinol (H(2)-DAR) ligand behaves as a binegative tetradentate chelating ligand coordinating through O,O atoms of both the carbonyl and phenolic C-O groups by replacing a molecule of PPh(3)/AsPh(3) and a hydride ion from the starting complexes. Further, all these complexes were also employed as new catalysts for the oxidation of primary and secondary alcohols in the presence of N-methylmorpholine-N-oxide (NMO) as a more viable co-oxidant. The free ligand and their metal complexes have also been screened for their antibacterial activity against the growth of gram +ve and gram -ve bacterial cultures.

Preparation, characterization, in-vitro drug release and cellular uptake of poly(caprolactone) grafted dextran copolymeric nanoparticles loaded with anticancer drug.

Biodegradable and biocompatible polymers that are engineered to nanostructures play a key role in providing solution for sustained chemotherapy. This study is focused on preparation, drug encapsulation efficiency, in-vitro drug release, in-vitro cellular uptake and cell viability of poly(caprolactone) grafted dextran (PGD) nanoparticles (NPs) formulation containing vinblastine as the anticancer drug. Drug-loaded PGD NPs were prepared by a modified oil/water emulsion method and characterized by laser light scattering, atomic force microscopy (AFM), and zeta potential. The drug encapsulation efficiency was determined spectrophotometrically and in-vitro drug release was estimated using dialysis bag. Breast cancer cell line (MCF-7) was used to image and measure the cellular uptake of fluorescent PGD NPs. Cancer cell viability was assessed by treating MCF-7 cells with vinblastine-loaded PGD NPs by crystal violet staining method. Result showed that the vinblastine-loaded PGD NPs were superior in properties such as drug encapsulation efficiency, the cellular uptake and the cancer cell mortality.

In vitro evaluation of poly(caporlactone) grafted dextran (PGD) nanoparticles with cancer cell.

This study dealt with the preparation and characterization of coumarin-6 loaded poly(caprolactone) grafted dextran (PGD) nanoparticles (NPs) and evaluation of cellular uptake by using human gastric cancer cell line (SNU-638), in vitro. The potential application of these PGD NPs for sustained drug delivery was evaluated by the quantification and localization of the cellular uptake of fluorescent PGD NPs. Coumarin-6 loaded PGD NPs were prepared by a modified oil/water emulsion technique and characterized by various physico-chemical methods such as, laser light scattering for particle size and size distribution, atomic force microscopy (AFM), zeta-potential and spectrofluorometry to identify the release of fluorescent molecules from the NPs. SNU-638 was used to measure the cellular uptake of fluorescent PGD NPs. Confocal laser scanning microscopic images clearly showed the internalization of NPs by the SNU-638 cells. Cell viability was assessed by treating the SNU-638 cells with PGD NPs for 48 h. The results reveal, that these biodegradable polymeric NPs holds promise in biomedical field as a carrier.

Preparation and drug release activity of scaffolds containing collagen and poly(caprolactone).

A new biodegradable polymeric scaffold was prepared by using collagen and poly(caprolatctone) (PCL). These scaffolds were found to be soft, spongy, and transparent in nature and characterized by thermogravimetric analysis and FTIR spectrum. To these biodegradable polymeric scaffolds, antibiotic drugs namely amikacin and gentamycin were incorporated separately to study their release pattern from scaffolds. Amikacin and gentamycin release activity of the scaffolds containing a constant quantity of collagen but different quantities of PCL were studied at various time intervals viz. 1, 4, 24, and 48 h by measuring the optical density at 257 and 255 nm, respectively.

Deposition of gold nanoparticles on electrospun MgTiO3 ceramic nanofibers.

A simple method to deposit spherical gold nanoparticles on the surface of MgTiO3 ceramic nanofibers is presented. Electrospun MgTiO3/poly(vinyl acetate) (PVAc) hybrid nanofibers were calcined at 650 degrees C to obtain phase pure ceramic MgTiO3 nanofibers with 100-150 nm diameters. These ceramic nanofibers were immersed in an aqueous solution of HAuCl4 containing poly(vinyl alcohol) (PVA) as capping agent followed by photoreduction at 365 nm to get a novel Au-MgTiO3 nanocomposite. The formation of gold nanoparticles upon irradiation was confirmed by the appearance of a surface plasmon band (SPB) at 590 nm in the UV-visible absorption spectra. The surface morphology and elemental compositions were analyzed by the scanning electron microscope (SEM) equipped with energy dispersive X-ray (EDX), and transmission electron microscope (TEM). X-ray diffraction (XRD) and selected area diffraction (SAED) pattern in TEM revealed the crystallization of gold by exhibiting strong diffractions correspond to Au(111) and Au(200) crystalline planes in addition to the MgTiO3 diffraction.

Spectral studies of SnO2 nanofibres prepared by electrospinning method.

Tin oxide nanofibres with 100-150 nm diameter has been prepared, for the first time by calcination of poly(vinyl acetate) (PVAc)/SnO2 composite fibres prepared by electrospinning method as precursor. Scanning electron microscopic images revealed cylindrical morphology of the fibres after calcination at 600 degrees C. Both, X-ray diffraction (XRD) and Raman spectral data confirmed the presence of phase pure tetragonal rutile tin oxide after calcination process. Room temperature photoluminescence (PL) spectra of tin oxide nanofibres under excitation at 325 nm wavelength show a strong green emission at 525 nm with a band gap of 2.41 eV. FT-IR spectra confirmed the formation of pure tin oxide after calcination at 600 degrees C and complete removal of PVAc during calcination. UV-vis spectrum of the fibres showed absorption at 315 nm due to the direct electron transfer in tin oxide.

Spectroscopic identification of S-Au interaction in cysteine capped gold nanoparticles.

This study deals with the synthesis of cysteine capped gold nanoparticles with an average size of 12 nm by borohydride reduction and spectroscopic identification of SAu interaction. We have studied the interaction of thiol with gold nanoparticles in aqueous medium by employing UV-vis, Raman, NMR, and FT-IR spectroscopy. The shifting of gold plasmon resonance in the UV-vis spectra shows the stabilization of gold nanoparticles by cysteine. The disappearance of S-H stretching in both the IR and Raman spectra and the shifting of the NMR signals of the protons in close proximity to the metal center supported the existence of the S-Au interaction in cysteine capped gold nanoparticles. The TEM images shows cysteine capped gold nanoparticles as distinct and spherical entities as compared to free colloidal gold nanoparticles.