The release behavior of doxorubicin hydrochloride from medicated fibers prepared by emulsion-electrospinning

The release behavior of a water-soluble small molecule drug from the drug-loaded nanofibers prepared by emulsion-electrospinning was investigated. Doxorubicin hydrochloride (Dox), a water-soluble anticancer agent, was used as the model drug. The laser scanning confocal microscopic images indicated that the drug was well incorporated into amphiphilic poly(ethylene glycol)-poly(L-lactic acid) (PEG-PLA) diblock copolymer nanofibers, forming "core-sheath" structured drug-loaded nanofibers.

Erbium-Complex-Doped Near-Infrared Luminescent and Magnetic

A near-infrared luminescent macroporous material (PL-Macromaterial) and a near-infrared luminescent/magnetic bifunctional macroporous material (MML-Macromaterial) were synthesized by using polystyrene microspheres (PS) and Fe3O4 @polystyrene core-shell nanoparticles (Fe3O4@PS), respectively, as templates. Both the PL-Macromaterial and the M/PL-Macromaterial show the characteristic emission of the Er 3, ion. Moreover, the M/PL-Macromaterial possesses superparamagnetic properties at room temperature.

Fabrication and characterization of uniform Fe3O4 octahedral micro-crystals

Uniform Fe3O4 octahedral microcrystals with perfect appearance have been successfully synthesized by a Triton X100-assisted polyol process. During the polyols process for the preparation of Fe3O4 octahedra. the introduction of Triton X100 decreases significantly the needed concentration of NaOH. The results show that Fe3O4 octahedra are composed of eight triangular sheets, which are equilateral triangles. The edge size of Fe3O4 octahedron is about 4 mu m. The magnetic properties of Fe3O4 octahedral particles were evaluated on a SQUID magnetometer at room temperature.

Synthesis of Titania in Ethanol/Acetic Acid Mixture Solvents: Phase and Morphology Variations

The phase and morphology variations of titania prepared in ethanol/acetic acid mixture solvents have been systematically investigated. X-ray diffraction results and microscopy observations reveal that pure anatase aggregates consisted of small nanoparticles, pure rutile microspheres comprised of nanofibers, and their mixtures could be obtained by varying ratios of ethanol to acetic acid under solvothermal conditions. The contents of anatase and rutile in the mixed phases also vary with the ratios of ethanol to acetic acid. Field emission scanning electron microscopy and high resolution transmission electron microscopy results show that the two phases are separated from each other in final products and form aggregates with morphologies resembling to their pure phase products obtained under favorable conditions. The as-produced rutile nanofibers, either in pure phase or in mixed phases, tend to grow into hollow microspheres.

Ordered magnetic core-manganese oxide shell nanostructures and their application in water treatment

In this paper, we have reported a facile method for the synthesis of ordered magnetic core-manganese oxide shell nanostructures. The process included two steps. First, manganese ferrite nanoparticles were obtained through a solvothermal method. Then, the manganese ferrite nanoparticles were mixed directly with KMnO4 solution without any additional modified procedures of the magnetic cores. It has been found that Mn element in the core can react with KMnO4 to form manganese oxide which acts as a seed for the in-situ growth of manganese oxide shells. This is significant for the controllable fabrication of symmetrical ordered manganese oxide shell structures. The shell thickness can be easily controlled through the reaction time. Transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray powder diffraction and energy-dispersive X-ray spectroscopy have been employed to characterize the products at different reaction time.

A magnetic, luminescent and mesoporous core-shell structured composite material as drug carrier

In this paper, hydrothermal synthesized Fe3O4 microspheres have been encapsulated with nonporous silica and a further layer of ordered mesoporous silica through a simple sol-gel process. The surface of the outer silica shell was further functionalized by the deposition of YVO4:Eu3+ phosphors, realizing a sandwich structured material with mesoporous, magnetic and luminescent properties. The multifunctional system was used as drug carrier to investigate the storage and release properties using ibuprofen (IBU) as model drug by the surface modification. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS), Fourier transform infrared spectroscopy (FT-IR), N-2 adsorption/desorption, photoluminescence (PL) spectra, and superconducting quantum interference device (SQUID) were used to characterized the samples.

Hydroxyapatite Nano- and Microcrystals with Multiform Morphologies: Controllable Synthesis and Luminescence Properties

Hydroxyapatite (Ca-5(PO4)(3)OH) nano- and microcrystals with multiform morphologies (separated nanowires, nanorods, microspheres, microflowers, and microsheets) have been successfully synthesized by a facile hydrothermal process. X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), photoluminescence (PL) spectra, kinetic decay, and electron paramagnetic resonance (EPR) were used to characterize the samples. The experimental results indicate that the obtained Ca-5(PO4)(3)OH samples show an intense and bright blue emission under long-wavelength UV light excitation. This blue emission might result from the CO2 center dot- radical impurities in the crystal lattice.

Magnetic Mesoporous Silica Spheres for Drug Targeting and Controlled Release

Magnetically functionalized mesoporous silica spheres with different size (average diameter, A.D.) from 150 nm to 2 mu m and pore size distribution were synthesized by generating magnetic FexOy nanoparticles onto the mesoporous silica hosts using the sol-gel method. The X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), N-2 adsorption/desorption results show that these composites conserved regular sphere morphology and ordered mesoporous structure after the formation of FexOy nanoparticles. XRD and X-ray photoelectron spectroscopy (XPS) analysis confirmed that the FexOy generated in these mesoporous silica hosts is mainly composed of gamma-Fe2O3. Magnetic measurements reveal that these composites with different gamma-Fe2O3 loading amounts possess super-paramagnetic properties at 300 K, and the saturation magnetization increases with increasing Fe ratio loaded.

Synthesis and characterization of monodisperse spherical SiO2@RE2O3 (RE = rare earth elements) and SiO2@Gd2O3:Ln(3+) (Ln = Eu, Tb, Dy, Sm, Er, Ho) particles with core-shell structure

Spherical SiO2 particles have been coated with rare earth oxide layers by a Pechini sol-gel process, leading to the formation of core-shell structured SiO2@RE2O3 (RE = rare earth elements) and SiO2@Gd2O3:Ln(3+) (Ln = Eu, Tb, Dy, Sm, Er, Ho) particles. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), photoluminescence (PL), and cathodoluminescence spectra as well as lifetimes were used to characterize the resulting SiO2@RE2O3 (RE = rare earth elements) and SiO2@Gd2O3:Ln(3+) (Eu3+, Tb3+, Dy3+, Sm3+, Er3+, Ho3+) samples. The obtained core-shell phosphors have perfect spherical shape with narrow size distribution (average size ca. 380 nm), smooth surface and non-agglomeration. The thickness of shells could be easily controlled by changing the number of deposition cycles (40 nm for two deposition cycles).

Nanoreactor of Fe3O4@SiO2 Core-Shell Structure with Nanochannels for Efficient Catalysis

We introduced a new nanoreactor system consisting of nanochannel-filled Fe3O4 core and SiO2 shell. Different morphologies of Fe3O4@SiO2 Core-shell nanostructures could be obtained through simple HCI etching of the magnetic cores. The outer silica shells were permeable and the Fe3O4 cores were accessible to the reactants. Therefore, the present nanoreactor system was applied to catalyze the reduction of H2O2, and it showed outstanding catalytic activity compared with bare Fe3O4 or Fe3O4@SiO2 core-shell nanoparticles.

High-density gold nanoparticles supported on a [Ru(bpy)(3)](2+)-doped silica/Fe3O4 nanocomposite: Facile preparation, magnetically induced immobilization, and applications in ECL detection

A large-scale process combined sonication with self-assembly techniques for the preparation of high-density gold nanoparticles supported on a [Ru(bpy)(3)](2+)-doped silica/Fe3O4 nanocomposite (GNRSF) is provided. The obtained hybrid nanomaterials containing Fe3O4 spheres have high saturation magnetization, which leads to their effective immobilization on the surface of an ITO electrode through simple manipulation by an external magnetic field (without the need of a special immobilization apparatus). Furthermore, this hybrid nanomaterial film exhibits a good and very stable electrochemiluminescence (ECL) behavior, which gives a linear response for tripropylamine (TPA) concentrations between 5 mu m and 0.21 mM, with a detection limit in the micromolar range. The sensitivity of this ECL sensor can be easily controlled by the amount of [Ru(bpy)(3)](2+) immobilized on the hybrid nanomaterials (that is, varying the amount of [Ru(bpy)(3)](2+) during GNRSF synthesis).

A simple method to prepare titania nanomaterials of core-shell structure, hollow nanospheres and mesoporous nanoparticles

A simple method to prepare titania nanomaterials of core-shell structure, hollow nanospheres and mesoporous nanoparticles has been developed. The core-shell nanostructures with NH4Cl as core and TiO2 center dot xH(2)O-NH4Cl as shell were prepared in nonaqueous system by the deposition on the surface of the aggregated NH4Cl crystals, which could be transformed into mesoporous anatase nanoparticles or hollow nanospheres by calcination at 500A degrees C or extraction with methanol, respectively. The hierarchical mesoporous nanostructures benefited the photocatalytic activities of the resultant titania nanomaterials, demonstrated by the UV light photodegradation of Methyl Orange.

EDTA-controlled one-pot preparation of novel shaped gold microcrystals and their application in surface-enhanced Raman scattering

We report a one-pot preparation method for a series of novel shaped gold microcrystals by simply mixing HAuCl4 with disodium salt of ethylenediaminetetraacetic acid (Na(2)EDTA). Under the different reaction temperatures, spinous structures, multipod microspheres, and rough surfaced microspheres were obtained. These microcrystals exhibit high surface-enhanced Raman scattering (SERS) activity.

Enantiomeric PLA-PEG block copolymers and their stereocomplex micelles used as rifampin delivery

A novelty approach to self-assembling stereocomplex micelles by enantiomeric PLA-PEG block copolymers as a drug delivery carrier was described. The particles were encapsulated by enantiomeric PLA-PEG stereocomplex to form nanoscale micelles different from the microspheres or the single micelles by PLLA or PDLA in the reported literatures. First, the block copolymers of enantiomeric poly(L-lactide)-poly(ethylene-glycol) (PLLA-PEG) and poly(D-lactide)-poly(ethylene-glycol) (PDLA-PEG) were synthesized by the ring-opening polymerization of L-lactide and D-lactide in the presence of monomethoxy PEG, respectively. Second, the stereocomplex block copolymer micelles were obtained by the self-assembly of the equimolar mixtures of enantiomeric PLA-PEG copolymers in water. These micelles possessed partially the crystallized hydrophobic cores with the critical micelle concentrations (cmc) in the range of 0.8-4.8 mg/l and the mean hydrodynamic diameters ranging from 40 to 120 nm. The micelle sizes and cmc values obviously depended on the hydrophobic block PLA content in the copolymer.Compared with the single PLLA-PEG or PDLA PEG micelles, the cmc values of the stereocomplex micelles became lower and the sizes of the stereocomplex micelles formed smaller. And lastly, the stereocomplex micelles encapsulated with rifampin were tested for the controlled release application.