The surfaces of bone sections were analyzed by ToF-SIMS and HR-SEM. All ToF-SIMS measurements were carried out with a TOF.SIMS 5-100 machine (IONTOF GmbH, Muenster, Germany). For analysis 25 keV Bi3+ primary cluster ions were used and the primary ion gun was operated in high-current bunched mode to obtain the best available mass resolution. The full width at half resolution (fwhm) was m/Δm > 4000 for Ca+ for the complete scan. Charge compensation was done with low energetic electrons. For imaging stage scans were carried out with a patch size of 400 × 400 µm2. Each patch was scanned 10 times with 2 shots per pixel and a pixel density of 120 pixel/mm. In total 12 scans with a primary ion current of 0.28–0.42 pA were recorded. For data evaluation we used the SurfaceLab 6.7 (IONTOF GmbH, Muenster, Germany) software. Detail images were taken in low current bunched mode with a lateral resolution of approximately 2 µm.
Scanning electron microscopy (SEM) analysis was carried out with a Zeiss Merlin microscope (Zeiss, Oberkochen, Germany) and EDS analysis with an x-max 50 mm2 detector (Oxford Instruments, Abingdon, UK) at 5 mm working distance and 10 kV acceleration voltage. In advance a thin carbon layer was deposited with an Edwards Scancoat Six to avoid sample charging. Data evaluation was done with the Aztec software from Oxford instruments.
Scanning electron microscopy (SEM) analysis was carried out with a Zeiss Merlin microscope (Zeiss, Oberkochen, Germany) and EDS analysis with an x-max 50 mm2 detector (Oxford Instruments, Abingdon, UK) at 5 mm working distance and 10 kV acceleration voltage. In advance a thin carbon layer was deposited with an Edwards Scancoat Six to avoid sample charging. Data evaluation was done with the Aztec software from Oxford instruments.