Methods to characterize in vivo corrosion

Various analytical methods have been used to determine the elemental components of biodegradable magnesium alloys (Mg, Al, Li, Zn, REE) in histological sections, bone, tissue and body fluids (Witte et al., 2008b) (see Table 10.2). The application of these methods for trace and ultra-trace analysis in small sample volumes is hampered by several problems. The typical concentrations of the elements mentioned above range from 1 p.g/L to about 1 mg/L in serum and from 1 mg/kg up to about 500 mg/kg for example in liver and bone. Thus, the sensitivity of several analytical methods 

3 Uncalcified histological section of an implanted Mg rod in bone tissue. White arrows indicate drop outs in the bone-implant interphase due to technical limitations inherently coupled to the cutting-grinding technique. Scale bar = 400 im. 

3 General and local corrosion rate determined non-destructively in 3D by SR liCT 

the remaining non-corroded metal volume as well as the sample surface was determined in three dimensions non-destructively on a micrometer scale. The reduction of metal implant volume could be converted into a corrosion rate by using a modification of the ASTM G31-72, 2004 equation (10.5) for weight loss measurements  

This method provides a non-destructively general corrosion rate of the implanted metal. A more local corrosion analysis is possible if the corrosion rates are calculated based on the pitting depth. It was shown that even slowly 

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