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The research herein includes methodology for eco-friendly preparation of selenium nanoparticles (SeNPs) using the broad-spectrum antibiotic, Megamox (Mega.). Characterization of SeNPs was done using UV-Visible spectroscopy, FTIR, XRD, DLS and TEM imaging. Additionally, the immunomodulatory, antioxidant and antimicrobial activities of both SeNPs and Mega. were checked against different strains of bacteria and fungi. TEM and DLS images showed that SeNPs are polydisperse spheres with mean diameter of 22.4 nm. FTIR analysis indicated that the hydroxyl and nitrogen moieties in Mega. were effective for reduction plus binding manner. According to the results of the nitro blue tetrazolium reduction test, both SeNPs and Mega. presented high intracellular killing activity, which confirmed their immunostimulatory effect. Antioxidant activity of SeNPs and Mega. were 90 and 82 %, respectively. SeNPs presented great activity facing multi-drug resistant bacteria and TB. SeNPs are considered promising cost-effective and eco-friendly anti-bacterial and anti-fungal agents that can represent a new potential nano-platform in both medical and infectious diseases control. [ABSTRACT FROM AUTHOR]

In the present work, Ni0.6Cd0.4DyxFe2-xO4 (x = 0.0, 0.05, 0.10, 0.15, 0.20) nanoparticles (NPs) were synthesized by using sol–gel method. X-ray diffraction (XRD) patterns confirmed that the pure and dysprosium substituted Ni–Cd ferrites are in single-phase spinel structures, while a trace of DyFeO3 appears as a minor phase for higher concentrations (x = 0.10, 0.15 and 0.20). The Debye–Scherrer's method and Williamson–Hall (W-H) method were used to evaluate the crystallite sizes and lattice strain. Scanning electron microscope (SEM) images show that reduction of grain size with Dy3+ content. Elemental composition features of samples were examined by Energy-dispersive X-ray spectroscopy (EDS). The average particles size estimated from transmission electron microscopy (TEM) analysis is in good agreement with results obtained from XRD. The results showed that saturation magnetization (Ms) decreases and coercivity (Hc) increases with an increase in Dy3+ concentrations. The dielectric constant was found to decrease with increasing Dy content in Ni–Cd ferrites. [ABSTRACT FROM AUTHOR]

A novel one-pot synthetic method to produce crystalline tri-octylphosphine (TOP) capped iron phosphide nanoparticles is reported here. Standard method of synthesizing FeP includes preparation of a precursor, sodium phosphide, which is finally reacted with ferric chloride (FeCl3).The methods for synthesizing iron phosphide (FeP), reported so far, rely on the use of toxic red or yellow phosphorus to generate the precursor, Sodium phosphide (Na3P). In present investigation, instead of red or yellow phosphorus, a relatively less toxic substance TOP and sodium metal (Na) have been used to yield Na3P. The synthesized nanoparticles were fully characterized by X-ray diffraction pattern (XRD), Infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), Transmission electron microscopy (TEM) and superconducting quantum interference device (SQUID) analyses. The results showed that the synthesized FeP nanoparticles have the characteristic orthorhombic crystal structures, with the size ∼10 nm and the coercivity 70 Oe at RT. [ABSTRACT FROM AUTHOR]

Abstract: A series of doped CeF3: RE3+ (RE3+: Tb3+, Eu3+ and Dy3+) nanoparticles were synthesized, with the aim of obtaining a white light emitting composition, by a simple polyol route at 160°C and characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), Fourier transform infrared spectroscopy (FT-IR) and photoluminescence. Uniformly distributed and highly water-dispersible rectangular nanoparticles (length ∼15–20nm, breadth ∼5–10nm) were obtained. The steady state and time resolved luminescence studies confirmed efficient energy transfer from the host to activator ions. Lifetime studies revealed that optimum luminescence is observed for 2.5mol% Dy3+ and 7.5mol%Tb3+. The energy transfer efficiencies (Ce3+ to activators) were found to be 89% for CeF3: Tb3+ (7.5mol%) nanoparticles and 60% for CeF3: Dy3+ (2.5mol%) nanoparticles. Different concentrations of Tb3+, Eu3+ and Dy3+ were doped to achieve a white light emitting phosphor for UV-based LEDs (light emitting diodes). Finally CeF3, triply doped with 2.0mol%Tb3+, 4.5mol% Eu3+ and 3.5mol% Dy3+, was found to have impressive chromaticity co-ordinates, close to broad day light. The colloidal solutions of doped CeF3 nanoparticles emitted bright green (Tb3+), blue (Dy3+) and white (triply doped) luminescence upon host excitation. Composites of poly methyl methacrylate (PMMA) and poly vinyl alcohol (PVA) were made with CeF3: 5.0mol%Tb3+, CeF3: 5.0mol% Dy3+ and triply doped white light emitting composition. The CeF3/PMMA (PVA) nanocomposite films, so obtained, are highly transparent (in the visible spectral range) and exhibit strong photoluminescence upon UV excitation. [Copyright &y& Elsevier]

Abstract The present study demonstrated the development of gemcitabine and betulinic acid co-encapsulated PLGA−PEG polymer nanoparticles for enhancing the chemotherapeutic response. This combinatorial PLGA-PEG nanoparticle was formulated using double emulsion and had size <200 nm. The developed nanoparticles were characterized using dynamic light scattering and transmission electron microscopy for their size and shape, respectively. The in vitro release of the drugs from combinatorial nanoparticles was predominantly followed by Fickian diffusion phenomenon. Study on hemocompatibilty approved the administration of this combinatorial nanoparticle for animal study. In vitro cytotoxicity study on Panc1 cells using MTT assay, reactive oxygen species production and cellular apoptotic assay demonstrated that combinatorial nanoparticle was more cytotoxic compared to native drugs solution. Furthermore, the combinatorial nanoparticle suppressed tumor growth more efficiently in Ehrlich (solid) tumor model than the native gemcitabine and betulinic acid at the same concentrations. These findings indicated that PLGA-PEG nanoparticle might be used to co-deliver multiple chemotherapeutic drugs with different properties for enhancing antitumor efficacy. Highlights • Development of gemcitabine and betulinic acid loaded PLGA−PEG nanoparticles. • Combinatorial nanoparticle was more cytotoxic compared to native drugs. • Mechanistic investigation was performed using ROS and apoptotic assay in PANC1 cells. • Combinatorial nanoparticle exhibited improved anti-tumor efficacy in solid tumor model. [ABSTRACT FROM AUTHOR]