Hemolysis effect and calcium-phosphate precipitation of heat-organic-film treated magnesium

• Published in: Transactions of Nonferrous Metals Society of China Vol. 16; no. 3; pp. 539 - 544
• Main Author: 高家诚 乔丽英 李龙川 王勇
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.06.2006; College of Materials Science and Engineering, Chongqing University, Chongqing 400030, China
• Subjects: biomaterials; corrosion resistance; heat-organic films; hemolysis; magnesium; 溶血效应; 生物材料; 磷酸钙; 腐蚀抗力; magnesium; heat-organic films; biomaterials; corrosion resistance; hemolysis
• ISSN: 1003-6326
• DOI: 10.1016/s1003-6326(06)60094-0

A heat-organic-films process was employed to induce calcium-phosphate apatites formation on magnesium, consequently the corrosion resistance and hemolysis properties of magnesium were improved for biomedical applications. Firstly, magnesium samples were heat-treated at 773 K for 10 h; secondly, stearic acid films were coated on the surface of the heat-treated magnesium. Then the surface modified magnesium was soaked in simulated body fluid （SBF） to test its corrosion resistance. The results show that the heat treatment process allows magnesium to form a dense oxide layer with a thickness of around 20 μm, thereby the surface modified magnesium has higher corrosion resistance. After 24 h in SBF island apatite was deposited on magnesium. The unevenly precipitates were characterized by XRD and FTIR as the mixture of hydroxyapatite（HA） and octacalcium phosphate（OCP）. The preliminary hemolysis experiment indicates that untreated magnesium has hemolytic effect （about 60%）; whereas the heat-organic film treated samples has no hemolytic effect. The mechanism of fast nucleation and growth of calcium-phosphate apatites on surface modified magnesium in SBF was also discussed.