Preparation of Bone-Like Apatite Coating on Surface of Ti-25Nb-2Zr Alloy by Biomimetic Growth Method

A bone-like apatite layer consisting of nano-crystals of apatite phase was prepared on the surface of Ti- 25Nb-2Zr alloy by chemical biomimetic growth method. TiNbZr alloy specimens were first oxidized at 500 ℃ for 2 h in the air. Then, they were immersed in 40 ℃ saturated NazHPO4 solution for 15 h and 25 ℃ saturated Ca （OH）2 solution for 8 h in turn for pre-calcification. The pre-calcified specimens were immersed in modified simulated body fluid up to 15 d for biomimetic growth. After common oxidization, amorphous titania and anatase were detected on the specimen surface. Except for the substantial amount of calcium and phosphorus, no new phase appeared on the pre-calcified specimens. After the coating process, it was found that the （002） orientation was the preferred orientation during the growing period of hydroxyapatite. The inorganic composition and structure of the coating are very similar to those of human thigh bone, which will be advantageous for its application as biomedical material.

Mesoscopic Models of Plants Composed of Metallic Nanowires

Various metallic structures of complex shape resembling living plant organisms （biomimetics） are produced as a result of self-assembly of nanowires growing on porous membranes in the course of pulse current electrodeposition. These structures occur if the electroplating is continued after the nanowires appear on the membrane surface. By varying the membrane ge- ometry, pulse current electroplating parameters, and alternating electrodeposition from two baths composed of a variety of electrolytes, diverse models were fabricated, including a hollow container with a wall thickness of 10 nm 20 nm. This biomimetic method suggests an analogy between the shape-forming processes of plants and their metallic models. Nanostruc- tured mesostructures of various metals （Ag, Pd, Ni）, alloys （PdNi, Pbln） and hybrid structures .（PdNi/Pb, PdNi/Pbln） were obtained. They can be of interest for fundamental research （self-assembly, morphogenesis） as well as for applications in nanotechnology （catalysis, nanoplasmonics, medicine, superhydrophobic surfaces）.

Preparation and application of mesoporous core-shell nanosilica using leucine derivative as template in effective drug delivery

Core-shell structured mesoporous silica nanoparticles have been firstly synthesized with the new template from L-leucine methyl ester hydrochloride(H-Leu-OMe·HCl).LMSNs were characterized by transmission electron microscopy(TEM),nitrogen adsorption/desorption,and small-angle X-ray diffraction(SAXRD),demonstrating a well-ordered mesostructure.After loading doxorubicin hydrochloride(Dox) into pores,considerable loading capacity of 30.5% and favorable cumulative release amount were obtained.MTT assay suggested that Dox-loaded LMSNs demonstrated great promise to anti-tumor.The use of MSNs with the synthesized template,as a drug delivery carrier,will exte nd the pharmaceutical applications of silica materials.