Development of strontium releasing implants capable of stimulating bone formation and inhibiting bone resorption is a desirable solution for curing osteoporosis. In this work, well-ordered SrTiO(3) nanotube arrays capable of Sr release at a slow rate and for a long time are successfully fabricated on titanium by simple hydrothermal treatment of anodized titania nanotubes. This surface architecture combines the functions of nanoscaled topography and Sr release to enhance osseointegration while at the same time leaving space for loading of other functional substances. In vitro experiments reveal that the SrTiO(3) nanotube arrays possess good biocompatibility and can induce precipitation of hydroxyapatite from simulated body fluids (SBF). This Ti-based implant with SrTiO(3) nanotube arrays is an ideal candidate for osteoporotic bone implants. The proposed method can also be extended to load other biologically useful elements such as Mg and Zn.
Fast degradation rates in the physiological environment constitute the main limitation for magnesium alloys used in biodegradable hard tissue implants. In this work, the corrosion behavior of AZ91 magnesium alloy in simulated body fluids (SBF) was systematically investigated to determine its performance in a physiological environment. The influence of the main constituent phases on the corrosion behavior was studied by in situ visual observation and scanning electron microscopy. Energy dispersive x-ray spectrometry and Fourier transfer infrared spectroscopy revealed that both calcium and magnesium phosphates are present in the corroded products besides magnesium oxide. Electrochemical methods including open circuit potential evolution and electrochemical impedance spectroscopy were used to investigate the mechanism. The corresponding electrode controlled processes and evolution of the corrosion products layer were discussed. The degradation rate after immersion in SBF for seven days was calculated from both the weight loss and hydrogen evolution methods.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.