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Báo cáo hóa học: " In Situ Mineralization of Magnetite Nanoparticles in Chitosan Hydrogel"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research In Situ Mineralization of Magnetite Nanoparticles in Chitosan Hydrogel | Nanoscale Res Lett 2009 4 1041-1046 DOI 10.1007 S11671-009-9355-1 NANO EXPRESS In Situ Mineralization of Magnetite Nanoparticles in Chitosan Hydrogel Yongliang Wang Baoqiang Li Yu Zhou Dechang Jia Received 26 February 2009 Accepted 17 May 2009 Published online 30 May 2009 to the authors 2009 Abstract Based on chelation effect between iron ions and amino groups of chitosan in situ mineralization of magnetite nanoparticles in chitosan hydrogel under ambient conditions was proposed. The chelation effect between iron ions and amino groups in CS-Fe complex which led to that chitosan hydrogel exerted a crucial control on the magnetite mineralization was proved by X-ray photoelectron spectrum. The composition morphology and size of the mineralized magnetite nanoparticles were characterized by X-ray diffraction Raman spectroscopy transmission electron microscopy and thermal gravity. The mineralized nanoparticles were nonstoichiometric magnetite with a unit formula of Fe2.85O4 and coated by a thin layer of chitosan. The mineralized magnetite nanoparticles with mean diameter of 13 nm dispersed in chitosan hydrogel uniformly. Magnetization measurement indicated that superparamagnetism behavior was exhibited. These magnetite nanoparticles mineralized in chitosan hydrogel have potential applications in the field of biotechnology. Moreover this method can also be used to synthesize other kinds of inorganic nanoparticles such as ZnO Fe2O3 and hydroxyapatite. Keywords Chitosan hydrogel Magnetite Mineralization Chelation Y. Wang B. Li H Y. Zhou D. Jia Institute for Advanced Ceramics Harbin Institute of Technology 150001 Harbin People s Republic of China e-mail libq@hit.edu.cn Y. Wang e-mail yongliang@hit.edu.cn Y. Zhou e-mail ce921@hit.edu.cn Introduction Mineralization leading to the formation of minerals in the presence of organic molecules is a widespread phenomenon in biological system 1 2 . In the process of mineralization a small amount of organic component not only .