Journal Name: Current Nanoscience
Article Title:Enhanced Luminescent Properties of Solution Combustion Synthesized Nanocrystalline Y3Al5O12:Eu3+ Phosphors
Author(s): Sumei Wang, Xurong Zhao, Shengming Zhou, Limin Zhou and Guodong Xia
Nanocrystalline Y3Al5O12:Eu3+ phosphors with particle size about 20-40 nm have been synthesized by a facile solution combustion method. XRD and TEM studies show that Y3Al5O12 nanocrystals can directly form at a low temperature of 825 °C and highly crystalline at 850 °C. With the increase of annealing temperature, the charge transfer band shows a blue shift due to the dielectric confinement effect. The color purity of Y3Al5O12:Eu3+ phosphors can be improved by decreasing the grain size of nanocrystals. Furthermore, the high concentration doping of Eu3+ can be realized in Y3Al5O12 nanocrystals, which will enhance the luminescent intensity. This work demonstrated that solution combustion is a feasible method to synthesize europium rare earth doped Y3Al5O12 nanocrystals with enhanced optical properties.
Article Title: Developing of A Novel Clinical Kit for Assaying of Alpha-fetoprotein Based on Luminescent and Magnetic Nanoparticles
Author(s): Shunan Shan, Xuhua Hu, Siyu Ni, Kai Li, Jing Li and Xingping Zhou
Alpha-fetoprotein ( α-FP, AFP) was the only serological marker currently available for the detection of hepatocellular carcinoma (HCC). As a novel biological luminescent label, the favorable properties of water-soluble CdTe quantum dots (QDs) have advantages over conventional fluorescent materials. Meantime, the magnetic separation technique has widely been applied to various aspects in biotechnology in recent years. In this paper, CdTe QDs and dextran–Fe3O4 magnetic nanoparticles were both applied on immunoassay for the determination of AFP concentration. Firstly, a mouse anti-human AFP antibody (primary antibody) was immobilized on magnetic nanoparticles, which were used as solid support. Secondly, another mouse anti-human AFP antibody (secondary antibody) was attached to the surface of the CdTe QDs via electrostatic interaction. It was found that when the pH value was 6.0, the volume ratio of CdTe (3 ×10-4 mol/L) to antibody (2 mg/mL) was 50:3, and the reaction time was more than 10 min, the complex of the secondary antibody and CdTe was formed and the strongest PL intensity was obtained. Thirdly, the above two complexes were conjugated with a serial of AFP concentrations. Then the relationship between the PL intensity and the AFP concentration was determined and the calibration equation— Y=k(X-9.31)/V—was obtained. Finally, ten samples of human serum were tested based on this equation. The results, to a large extent, were consistent with those obtained by Time-resolved Fluorescence. More importantly, the current method could be applied in many other antibody-antigen systems.
Adsorption and Removal of Sudan I, II from Organic Solutions by Oxidized Multiwalled Carbon Nanotubes
Author(s): Fei-Peng Jiao, Lei Zhou, Wei-Jie Yang, Jin-Gang Yu and Xiao-Qing Chen
Sudan dyes are toxic or carcinogenic even at low concentrations, which are illegally used as additives in food products to maintain their red color and thus stimulate sales of these products in the market recently. A facile adsorption procedure for the removal of Sudan I and II in n-hexane using oxidized multi-walled carbon nanotubes (O-MWCNTs) is presented in this paper. The effect of absorption conditions including absorption time, amount of adsorbent, initial concentration of Sudan I and II was examined. Two isotherm models were used to describe the adsorption equilibrium, while three kinetic models were applied to evaluate the adsorption process. The adsorption process and equilibrium for Sudan I and II were all proved to be fitted by the Langmuir model and second-order kinetic model. The O-MWCNTs possessed fast kinetics for Sudan I and II from n-hexane solvent with each saturation time of <30 min, and correspondingly the maximum adsorption capacities for Sudan I and II were 41.408 mg/g and 47.037 mg/g, respectively.