Superparamagnetic Iron Oxide Nanoparticles (SPION) Functionalized by Caffeic Acid (CFA)

In this research, we synthesized a novel caffeic acid-functionalized iron oxide nanoparticles (CFA-functionalized SPION) L929 (mouse fibroblast cell), U87 (glioblastoma brain cancer cell), MCF-7 (breast cancer cell), HeLa (cervix cancer cell), and A549 (human lung cancer cell) cell lines. Thermal decomposition and Stober methods were used to prepare APTES-capped SPION, respectively. The carboxylated polyethylene glycol (PEG-COOH), folic acid (FA), and caffeic acid (CFA) were attached to the surface of SPION via carboxylic/amine groups. Structural analysis (Rietveld analysis) confirmed the phase purity of the product. The conjugation of organics to the surface of SPION was followed with FT-IR spectroscopy and thermal gravimetric analysis (TGA). SEM analysis presented the spherical morphology of product with 13 +/- 3 nm particle size. And also, superparamagnetic property of product was deduced from VSM analysis. Uptake of CFA-functionalized SPION from the cell and release of CFA from CFA-functionalized SPION has been studied by using Prussian blue staining and spectrophotometer, respectively. Also, cell viability and cytotoxicity was tested by MTT and LDH assays. The uptake of CFA-functionalized SPION by HeLa, MCF-7, and U87 was higher than A549 and L929 cells. Also, caffeic acid release from CFA-functionalized SPION increased at an acidic environment (pH 4.4). A newly synthesized CFA-functionalized SPION in all used concentrations decreased cell viability and increased cytotoxicity at 24th and 48th hours. The results showed that the CFA-functionalized SPION is a potential anticancer agent for cancer therapy

Synthesis and Characterization of Carboxylated Luteolin (CL)-Functionalized SPION

In this study, a stable carboxylated luteolin (CL)-functionalized superparamagnetic iron oxide nanoparticle (SPION) as a potential drug carrier for in vitro analysis of L929 (mouse fibroblast), U87 (glioblastoma (brain cancer)), MCF-7 (breast cancer), HeLa (cervix cancer), and A549 (human lung cancer) cell lines has been synthesized. Thermal decomposition and Stober methods were used to prepare 3-aminopropyl triethoxysilane-capped SPIONs respectively. Carboxylated polyethylene glycol (PEG-COOH), folic acid (FA), and CL were conjugated on the surface via a carboxylic/amine group using the nanoprecipitation method respectively. Internalization of CL-functionalized SPION and the release of luteolin from it has been studied using Prussian blue staining and spectrophotometry respectively. The cytotoxicity of CL-functionalized SPION on cell lines was tested by MTT assay. Internalization of product by HeLa, MCF-7, and U87 was higher than A549 and L929 cells. It was observed that luteolin release increased in an acidic environment (pH 5.4). A newly synthesized SPION-FA-PEG in all concentrations (except 500 mu g/mL) did not show notable toxicity against L929, U87, MCF-7, HeLa, and A549. However, the product in all used concentrations decreased cell viability at the 24th and 48th hours. This study confirmed that the product has a potential to be used as an anti-cancer CL-functionalized SPION for targeted drug delivery

Synthesis of magnetically recyclable MnFe2O4@SiO2@Ag nanocatalyst: Its high catalytic performances for azo dyes and nitro compounds reduction

In this study, magnetically recycable MnFe2O4@SiO2@Ag nanocatalyst (MnFe2O4@SiO2@Ag MRCs) has been synthesized through co-precipition and chemical reduction method. XRD analysis confirmed the synthesis of single phase nanoproduct with crystallite size of 10 nm. VSM measurements showed the superparamagnetic property of the product. Catalytic studies showed that MnFe2O4@SiO2@Ag MRC could catalyze the reduction of the various azo compounds like methyl orange (MO), methylene blue (MB), eosin Y (EY), and rhodamine B (RhB) and also aromatic nitro compounds such as 4-nitrophenol (4-NP), 4-nitroaniline (4-NA) and 2-nitroaniline (2-NA). Moreover, the magnetic nanocatalyst showed an excellent reusability properties that remained unchanged after several cycles. Therefore, MnFe2O4@SiO2@Ag is the potential candidate for the application of organic pollutants for wastewater treatment. (C) 2016 Elsevier B.V. All rights reserved

Electrical and Dielectric Characterization of Bi-La Ion-Substituted Barium Hexaferrites

BaLa (x) Bi (x) Fe12-2xO19 (0.0 ae x ae 0.5) hexaferrites were produced by solid-state synthesis route, and the effect of Bi3+ and La3+ substitutions on electrical and dielectric properties of barium hexaferrite material were investigated. It is noticed that ac conductivity of barium (BaM) increases slightly with ionic substitutions of both La3+ and Bi3+ and then decreases. Ac conductivity is increased with increasing frequency at lower temperatures then remains constant for higher temperatures. This type of conductivity attitude could be originated from the indication of both electronics and polaron hopping mechanisms. The dielectric properties of BaLa (x) Bi (x) Fe12-2xO19 (0.0 ae x ae 0.5) hexaferrites represent a very interesting tunability as functions of frequency, temperature, and Bi3+ and La3+ ions

Secondary Metabolites Isolated from an Endophytic Phoma sp. – Absolute Configuration of Tetrahydropyrenophorol Using the Solid-State TDDFT CD Methodology

The known macrolide pyrenophorol (synonym helmidiol) (1), the new 2,3,10,11-tetrahydropyrenophorol (3), and (4S,7R)- 4,7-dihydroxyoctanoic acid (4), the monomeric acid of the sixteen-membered cyclic diolide 1, were isolated from an endophytic Phoma sp. The relative configuration of tetrahydropyrenophorol (3) was confirmed by X-ray single crystal analysis and its absolute configuration determined by the solid-state TDDFT CD methodology. Compounds 1 and 4 show antifungal activity and the acid 4 is also an algicide

Magnetic properties and hyperfine interactions of Co1-2xNixMnxFe2O4 nanoparticles

Col-2xNixMnxFe2O4 (0.0 <= x <= 0.5) nanoparticles (NPs) were prepared via citrate assisted microwave combustion route. XRD analysis confirmed the cubic structure (spinel) of all samples. Average crystallite size of products (obtained from (311) diffraction line) was in the range of 32.9-43.4 nm. The intense peak appearing at around 531 cm(-1) in FT-IR was attributed to the formation of a spinel ferrite. Magnetic properties of the products were investigated by room temperature vibrating sample magnetometer and Mossbauer spectroscopy. The magnetic parameters have been found to strongly depend on the Ni and Mn concentrations. The saturation magnetization continuously decreases with the increasing of the concentration (x). We found that Ni0.5Mn0.5Fe2O4 NP has superparamagnetic character at room temperature. This result was also verified by Mossbauer analysis. Scanning electron microscopic analysis revealed the cubic morphology of all products, EDX and elemental mapping analyses confirmed the expected composition of each product

Absolute Configurations of Globosuxanthone A and Secondary Metabolites from Microdiplodia sp. – A Novel Solid-State CD/TDDFT Approach

The absolute configuration of a potent new antitumor dihydroxanthenone, globosuxanthone A (1), active against human solid tumor cell lines and isolated by Gunatilaka et al. from Chaetomium globosum Ames[1] and in this study from the endophytic fungus Microdiplodia sp., was established by a new methodology. In this new approach, the Cartesian coordinates of the X-ray data serve as input geometry for quantum mechanical calculation of the theoretical CD spectrum. Comparison with the solid-state CD spectrum gives a very good match, since the calculated and the experimentally acquired data are derived from the very same single conformation

Electrical and Dielectric Properties of Y3+-Substituted Barium Hexaferrites

In this study, Y3+ ion-substituted M-type barium hexaferrites (BaM; BaFe12O19) were fabricated via facile ceramic route. As-prepared powders were characterized by X-ray powder diffractometry (XRD), Fourier transform infrared (FT-IR) spectroscopy, and impedance spectroscopy. XRD (Rietveld) analyses confirmed the presence of a single characterization of all samples (except x = 0.0 and 0.1 samples). The crystallite sizes of products are found in the range of 47.2-63.2 nm. Spectral analysis (FT-IR) also presented the formation of spinel structure for all products. The ac conductivity of the substituted samples was found to initially decrease slightly with increase in Y3+ compared with unsubstituted, and then variation tendency changes at the medium substitution ranges are observed with a different attitude against temperature. In the end, the lower conductivity for high substitutions is recorded and increases as functions of frequency while it also increases with the elevation of temperature. It was observed that ac conductivities of products increased by increasing frequency which indicate that observed ac conductivity is due to both electronic and polaron hopping mechanism

Magnetic and microstructural features of Dy3+ substituted NiFe2O4 nanoparticles derived by sol-gel approach

This study explored the microstructural and magnetic features of NiFe2-xDyxO4 (x <= 0.10) NPs (nanoparticles) that were synthesized by sol-gel auto-combustion method. The single phase of spinel ferrite has been verified for all samples without any impurity. The cubic morphology of the products was also showed by SEM. Room temperature (300 K) and 10 K magnetization curves were recorded applying a dc magnetic field up to +/- 50 kOe and it was observed that magnetic features of NiFe2O4 NPs significantly changed by the substitution of Dy3+ ion. Magnetization measurements showed low order of 300 and 10 K magnetic parameters (such as K-eff, coercivity and anisotropy field values), revealing soft ferrimagnetic behaviors of all pristine and doped NiDyxFe2-xO4 (0.00 <= x <= 0.10) NPs at both 300 and 10 K. Pristine NiFe2O4 has maximum magnetic moment and saturation magnetization values among all samples. Dy3+ substitution showed a slight decrement in magnetization values compared with pristine sample. A slight increase in coercivity was noticed with Dy3+ substitution. Squareness ratios (SQRs) have a range between 0.144 and 0.324. These values are smaller than the theoretical limit of 0.50, implying the multi-domain nature for NPs. Blocking temperature (T-B) was calculated as 28 K for NiFe2O4 NPs