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A novel chemical reduction method was reported to prepare tunable spherical or belted morphologies of nano-selenium (Se) based on cellulose nanocrystal (CNC). The homogeneous Se nanospheres with size of about 36 nm can be found for Se-Sphere-12H by adding ascorbic acid (VC) as assisted reducing agent. The Se nanobelt with a length of about 800 nm can be observed for Se-Belt-12H through one-pot reaction of CNC with sodium selenite (Na 2 SeO 3 ) under hydrothermal conditions. Moreover, Se-Belt-12H exhibited the higher crystallinity of 96.10% and maximum thermal degradation temperature (T max ) of 479.4 °C, the highest capacitance and the smallest internal resistance. [ABSTRACT FROM AUTHOR]

A facile and green reversed-phase microemulsion co-precipitation method has been developed for fabrication of CaCO 3 -based composite nanocarriers (NCs) with hyaluronic acid (HA) coatings for oral delivery of insulin. The cell viability of resultant CaCO 3 -based composite NCs against HT-29 cells was analyzed with different concentration. The chemical stability of loaded insulin against digestive enzyme was established in presence of simulated gastric fluid (SGF) containing pepsin. The uptake behavior of HT-29 cells was evaluated by confocal laser scanning microscope (CLSM). After oral administration to the diabetic rats, an effective hypoglycemic effect was obtained compared with subcutaneous injection of insulin. [ABSTRACT FROM AUTHOR]

Abstract: The influence of soluble silk sericin (SS) protein on the formation of CaCO3 particles was investigated and the CaCO3 particles were then used as a template to synthesize the hydroxyapatite microspheres. The SS showed a strong preference to the mineralization of vaterite and the fine controls over the shape, size and uniformity of vaterite were carried out by the variation of pH value and reaction time in the presence of SS. Using the vaterites as a template, the homogeneous and monodispersed hydroxyapatite microspheres, copying faithfully the shape and size of original vaterites, were fabricated under the assistance of microwave irradiation. The research may provide a feasible method for the fabrication of hydroxyapatite-based biomaterials with controllable configuration. [Copyright &y& Elsevier]

Abstract: The injectable chitosan/β-glycerophosphate (CS/GP) hydrogels were prepared with dexamethasone (Dex)/recombinant human bone morphogenetic protein (rhBMP-2) loaded hydroxyapatite nanoparticles (nHAP). The obtained samples were characterized by TEM, SEM, XRD and nitrogen adsorption tests, and the effect of Dex and rhBMP-2 on the mesenchymal stem cells (MSCs) was evaluated. The results showed that nHAP could be dispersed homogeneously in the matrix of injectable CS/GP hydrogels and the combination of Dex and rhBMP-2 could promote the proliferation and osteoblastic differentiation of MSCs, indicating that the prepared injectable CS/GP hydrogels with Dex and rhBMP-2 loaded nHAP have great potential in different orthopedic regenerative applications. [Copyright &y& Elsevier]

Abstract: The purpose of this study was to investigate the effect of amino acid on the morphology and crystallinity of nano-sized hydroxyapatite (HAP) crystals via a chemical precipitation method in the presence of l-lysine and l-tyrosine at different concentrations. The products were characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. The results showed the effect of l-lysine and l-tyrosine on the crystal growth of HAP was at opposite poles, i.e., the crystal growth was inhibited by l-lysine but promoted by l-tyrosine depending on the amino acid content. The mechanism of HAP crystal growth was also proposed. [Copyright &y& Elsevier]

Abstract: The purpose of this study was to investigate the effect of silk sericin (SS) on the morphology and crystallinity of hydroxyapatite (HAp) crystals synthesized at the pH 7.4–12 and 50°C via a biomimetic method. Using X-ray diffraction (XRD), transmission electron microscope (TEM) and high-resolution transmission electron microscope (HRTEM), it was revealed that a homogeneous assembly could be obtained in the presence of SS, which held a highly ordered microstructure and poor crystallinity. But in the absence of SS, an oriented aggregate could be prepared at 50°C and pH 10, which held more confused crystal lattice lines. The results proved that the biomimetic structure of HAp could be constructed under the controlled reaction conditions, which may offer a new clue on the understanding of the process of biomineralization. [ABSTRACT FROM AUTHOR]