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Simple, rapid, and sensitive detection of CD44 is of paramount importance since it plays pivotal roles in tumor initiation, growth and metastasis. Herein, we describe a novel method for sensitive, visual and facile fluorescence detection of CD44 and CD44-mediated cancer cell imaging, using a probe based on cationic conjugated polymer (CCP)-PFEP and fluoresceinamine-hyaluronan (FA-HA). HA is an anionic natural glycosaminoglycan that can specifically bind to the overexpressed CD44 on various kinds of cancer cells. PFEP and FA-HA formed a complex through electronic interactions, resulting in a highly efficient fluorescence resonance energy transfer (FRET) from PFEP to FA-HA; moreover, the efficiencies of FRET correlated with the concentrations of CD44 because the specific binding of HA-CD44 would separate FA-HA away from PFEP. This method did not require laborious and expensive dual-labeling or protein-labeling needed in previously reported detection methods of CD44. Just mix the sample and test solution containing the PFEP/FA-HA complex, and the results allowed naked-eye detection by observing fluorescent color of solutions with the assistance of a UV lamp. Most importantly, the use of a conjugated polymer with excellent amplification property as well as the specific binding of HA-CD44 endowed this method with high sensitivity and specificity, making it applicable for reliable quantitative detection of CD44. Furthermore, the PFEP/FA-HA complex formed nanoparticles in aqueous solution, and the nanoparticles can be selectively taken up by MCF-7 cells (cancer cell) through the HA-CD44 interaction, thereby giving rise to a dual-color tumor-targeted imaging probe with good photostability. The development of this fluorescent probe showed promising potential to make a reliable and routine method available for early diagnosis of cancer.

Abstract: Well-dispersed α-Fe2O3 parallelepiped nanocrystals have been successfully prepared via a hydrothermal synthetic route. The shapes and structures of the products were characterized by using powder X-ray diffraction and scanning electron microscopy. The results showed that the α-Fe2O3 samples have a parallelepiped shape with an average parallel side of 80–90nm and thickness of 60–70nm. The parallelepiped nanocrystals exhibited a ferromagnetic behavior with the coercive force, saturation magnetization, and remanent magnetization of 920Oe, 0.44emu/g, and 0.17emu/g, respectively. The crystal growth process was discussed on the basis of time-dependent experimental results. [Copyright &y& Elsevier]

Mono-dispersed oxide and hydroxide nanoparticles have been synthesized through the solvothermal process in alcohol-water mixtures. The products were characterized by powder x-ray diffraction (XRD) and scanning electron microscopy (SEM). Plate-like nanoparticles are obtained for Bi2O2.33, Fe2O3, and Cd(OH)2, and spherical nanoparticles are obtained for SnO2. The growth mechanism for the mono-dispersed nanoparticles has been preliminarily discussed. [ABSTRACT FROM AUTHOR]

Uniform cubic-shaped PbTe and PbSe nanocrystals have been synthesized through the surfactant-assisted hydrothermal reaction between Pb(NO3)2 and Te or Se powders with hydrazine hydrate as reducing reagent. The products were characterized by powder x-ray diffraction (XRD) and transmission electron microscopy (TEM). It was found that the shapes of nanocubes are well controlled by using ethylenediaminetetraacetic acid as chelating reagent and in the presence of poly(vinyl-pyrrolidone). [ABSTRACT FROM AUTHOR]

Abstract: Flake-like silver nanoparticles have been synthesized in large quantity by simply aging the aqueous solution of silver and urotropine in the presence of poly-(vinylpyrrolidone) (PVP). Silver nanoflakes of different shapes from circular to polygonal could be obtained in different reaction stages. PVP molecules play an important role in the anisotropic growth of silver nanoflakes. The as-synthesized silver colloidal solution remained stable for at least 1 month. Electron diffraction analysis showed that the nanoflakes are well crystallized. The UV-VIS absorption properties have also been studied. [Copyright &y& Elsevier]

Abstract: CdS microspheres with hierarchical structures were prepared with sodium dodecylbenzenesulfonate (SDBS) as structure directing reagent. SEM analysis indicated that the CdS microspheres were constructed with CdS nanosheets, which were further built up with assembled CdS nanoparticles. Optical investigation showed that the obtained CdS microspheres have an UV–vis absorption at 445nm and photoluminescence (PL) emissions at 498 and 573nm. The CdS hierarchical microspheres were immobilized on a glassy carbon electrode and the electrochemiluminescence (ECL) properties were investigated. The first application to sensing H2O2 was studied based on ECL from CdS hierarchical microspheres. A linear relation between the ECL intensity and H2O2 concentration, I =2.4212+2.1713 c, was obtained with a detection limit of 1×10−8 mol·L−1. [Copyright &y& Elsevier]