Hongxia Peng

Fe3O4@ZnS@Glycine nanoparticle as a novel microwave stimulus controlled drug release system

The stimuli-responsive controlled drug delivery system is highly desirable for an efficient cancer treatment approach. Herein, we have successfully developed a novel multifunctional microwave stimulus controlled anticancer drug release system based on magnetic Fe3O4@ZnS@Glycine nanoparticles. Fe3O4 core has a high magnetization saturation value for drug targeting under foreign magnetic fields. ZnS shells can efficiently convert microwave energy into thermal energy for microwave-triggered drug release. The glycine-modified layer of nanoparticles provides active group (–NH2) for the loading of drug molecules by hydrogen bond. The in vitro studies have clearly demonstrated the feasibility and advantage of the novel nanocarriers for remote-controlled drug release systems.Graphical AbstractWe combined the advantages of ZnS nanoparticles with those of Fe3O4 and glycine to create a new drug delivery system, which is capable of carrying drug molecules and triggered release of the drug by microwave treatment.

Egg albumin-assisted sol–gel synthesis and photo-catalytic activity of SnO 2 micro/nano-structured biscuits

SnO2 micro/nano-structured biscuits had been successfully prepared via egg albumin-assisted sol–gel procedure. The typical sample calcined at 900 °C was pure SnO2 with a tetragonal rutile structure, constructed by the numerous pomegranate seed-like irregular nanoparticles in the range of ~100 to ~400 nm. The complexation of egg albumin and tin ions and the bonding characteristics of functional groups had been confirmed. The band gap energy values of samples were apparently higher than the reference value of bulk matter, which could be assigned to a well-known effect that small particles tended to exhibit increased band gaps. It was revealed that with the increase of the calcined temperature the photoluminescence efficiency increased. The sample at 500 °C had the higher photocatalytic activity and the higher mean photo-degradation rate of MO was 88.1 ± 1.2% as compared to other samples, which could be assigned to the lower value of band gap due to the defect levels in the band gap from the impurities formed during the growth and the lower photoluminescence efficiency, beneficial to electrons transfer and reducing the combination of electron and hole, which resulted in better photocatalytic activity.Graphical abstract

Thermal Stability and Spectral Properties of Tm 3+ -Yb 3+ CO-Doped Tellurite Glasses

Glasses of the system 75TeO2–20ZnO–5La2O3–0.8Tm2O3–xYb2O3 were prepared by high temperature melt cooling method. Results of differential scanning calorimetry indicate that, all glass samples have excellent thermal stability. Judd–Ofelt strength parameters, spontaneous emission probabilities, fluorescence branching rations, fluorescence radiative lifetime of Tm3+ ions in tellurite glass were calculated. The impact of Yb3+ concentration on the fluorescence properties of Tm3+ ions in the S band under the pumping wavelength of 465 nm was investigated in a suggestion that, 3H4 radiative lifetimes will be prolonged and the performance of optical amplifier gain of Tm3+ in tellurite glass co-doped with 0.5 mol % Yb3+ ions will be improved.

Synthesis of porous GdF3:Er3+,Yb3+–COOH core–shell structured bi-functional nanoparticles for drug delivery

The authors synthesised porous GdF3:Er3+,Yb3+-COOH core-shell structured bi-functional nanoparticles through a one-step hydrothermal route during which ethylene diamine tetraacetic acid) was bound to the surface of the nanoparticles. It has high up-conversion emission intensity for monitoring the drug release process and magnetisation saturation value (10.2 emu/g) for drug targeting under foreign magnetic fields. Moreover, porous GdF3:Er3+,Yb3+ as drug carriers with a high drug-loading efficiency. cis-Dichlorodiammineplatinum(II) (cisplatin, CDDP)-loaded GdF3:Er3+,Yb3+ nanoparticles (GdF3:Er3+,Yb3+-CDDP) were characterised by the Fourier transform infrared spectra, and CDDP was loaded in the form of electrostatic interaction and hydrogen bonds. Compared with CDDP alone, GdF3:Er3+,Yb3+-CDDP nanoparticles increase concentration of CDDP in the target site and enhance its anticancer efficiency. Therefore, the as-prepared GdF3:Er3+,Yb3+-COOH nanoparticles allow simultaneous targeted drug delivery and monitoring as promising anti-cancer theranostic agents.

Preparation of Porous γ-Fe2O3@mWO3 Multifunctional Nanoparticles for Drug Loading and Controlled Release

BACKGROUND The use of chemotherapy drug is hindered by relatively low selectivity toward cancer cells and severe side effects from uptake by noncancerous cells and tissue. Thus, targeted drug delivery systems are preferred to increase the efficiency of drug delivery to specific tissues as well as to decrease its side effects. The aims of this paper are develop microwave-triggered controlled-release drug delivery systems using porous γ-Fe2O3@mWO3 multifunctional core-shell nanoparticles. We also studied its magnetic- microwave to heat responsive properties and large specific surface area. We chose ibuprofen (IBU) as a model drug to evaluate the loading and release function of the γ- Fe2O3@mWO3 nanoparticles. METHODS We used a direct precipitation method and thermal decomposition of CTAB template method to synthesize core-shell structured γ-Fe2O3@mWO3 nanoparticles. The specific surface areas were calculated by the Brunauer-Emmett-Teller (BET) method. The load drug and controlled release of the γ-Fe2O3@mWO3 triggered by microwave was determined with ultraviolet-visible spectroscopic analysis. RESULTS The γ-Fe2O3@mWO3 nanoparticles possesses high surface area of 100.09 m2/g, provides large accessible pore diameter of 6.0 nm for adsorption of drug molecules, high magnetization saturation value of 43.6 emu/g for drug targeting under foreign magnetic fields, quickly convert electromagnetic energy into thermal energy for controlled release by microwave-triggered which was caused by mWO3 shell. The IBU release of over 78% under microwave discontinuous irradiation out classes the 0.15% within 20s only stirring release. This multifunctional material shows good performance for targeting delivery and mWO3 microwave controlled release of anticancer drugs based on all the properties they possess. CONCLUSION The porous shell and the introduction of absorbing material not only increased the drug loading efficiency of the nanoparticles but also realized the microwave-stimulated anticancer drug controlled release. The nanoparticles would be very promising for microwave-induced controlled drug release, targeted drug delivery and hyperthermia therapy using microwave.

Synthesis of TiC–TiB2 composite powders via carbothermal reduction and its reaction mechanism

ABSTRACT Titanium carbide–titanium diboride (TiC–TiB2) composite powders were synthesised through a carbothermal reduction method by using titanium dioxide, boric acid, and different carbon sources (namely, carbon black, sucrose, and glucose) as starting materials. The thermal decomposition behaviour of the precursors was studied by thermogravimetry–differential thermal analyser. Phase compositions and morphologies of the synthesised products were characterised by X-ray diffractometer and scanning electron microscope. When n(Ti):n(B):n(C) = 1.0:2.5:5.0, the blended stock mainly formed TiB2 with sucrose or glucose as a carbon source, whereas the stock produced TiC when carbon black was the source. At an optimum reaction temperature, the particles of the powders synthesised from carbon black as a carbon source were the smallest at approximately 100 nm. With increasing amount of boric acid in the precursor, the morphologies of the samples changed into less spherical particles, and more flaky grains and small particles with irregular structures were observed.

A simple approach for the synthesis of bi-functional Fe3O4@MgO core–shell nanoparticles with magnetic-microwave to heat responsive properties

Core–shell structure nanomaterials have attracted considerable attention owing to their unique structure and promising applications in drug delivery and water treatment. A facile direct precipitation method has been developed for the synthesis of nanoparticles with bi functional magnetic to heat responsive properties with Fe3O4 nanoparticles as the core and MgO as the shell. Transmission electron microscopy (TEM) images revealed that the obtained bi-functional nanoparticles had a core–shell structure and a spherical morphology. The average size of the nanoparticle was ∼350 nm, and the thickness of the shell was ∼20 nm. The X-ray diffraction (XRD) patterns showed a cubic spinel structure of the Fe3O4 core and the MgO shell. The nanoparticles showed both strong magnetic and unique microwave to heat responsive properties, which may lead to development of nanoparticles with great potential for applications in drug targeting, controlled release, chemo- and microwave-thermal combination therapy and water treatment.