Liu Shuiping

Controlled release of dual drugs from emulsion electrospun nanofibrous mats

The purpose of this work is to develop a novel type of tissue engineering scaffold or drugs delivery carrier with the capability of encapsulation and controlled release drugs. In this study, Rhodamine B and Bovine Serum Albumin (BSA) were successfully incorporated into nanofibers by means of emulsion electrospinning. The morphology of composite nanofibers was studied by Scanning Electron Microscopy (SEM). The composite nanofibrous mats made from emulsion electrospinning were characterized by water contact angle measurement and X-ray diffraction. In vitro dual drugs release behaviors from composite nanofibrous mats were investigated. The results indicated that the incorporated drug and/or proteins in composite fibrous mats made from electrospinning could be control released by adjusting the processes of emulsions preparation.

Preparation of LaTiO2N photocatalyst with a large surface area

In this following communication, a new nanocrystalline photocatalyst LaTiO2N with a large surface area of 27.5 m2/g was synthesized by nitridation of amorphous La2O3/TiO2 composite powder at 900°C for 8 h using NH3 as the reactant gas, and the co-precipitate method was used to synthesize the high active amorphous La2O3/TiO2 composite powder. The X-ray powder diffraction (XRD) and transmission electron microscopy (TEM) results revealed that the as-prepared LaTiO2N nanocrystals had a mean diameter of about 30 nm. With increasing the nitrided temperature from 700°C to 900°C, it can be seen that the color of the oxynitride vary from yellow to red, and the specific surface area of the sample became lower since the high temperature can lead to the coalescence and aggregation of the nanoparticles. Both a higher nitridation temperature and a longer nitridation time can lead to a higher nitrogen content of the oxynitride. The TEM of the oxynitride obtained at 700°C, 800°C revealed some voids are in the oxynitride nanoparticles, which may be attribute to the density difference between oxide and oxynitride. The band gap energy of LaTiO2N was estimated to be 2.1 eV for its absorption band was founded to extend to 600 nm, it indicated that the synthesized oxynitrides displayed good light absorption properties not only in the ultraviolet light but also in the visible light region. Its high specific surface area and narrow band gap energy may guarantee photocatalytic activity under visible light excitation.