In vivo synthesis of calcium oxalate whiskers on CoCrMo alloy surfaces via biomineralization.

Surface treatments using bio-technology are valuable and fascinating in the sense that such treatments are natural and yield good biocompatibility. Calcium oxalate whiskers for biomedical applications were successfully synthesized on the CoCrMo alloy surfaces implanted in Aloe leaves which consist of many active bio-chemical elements. The effect of surface wettability and surface morphology on the formation of whiskers was investigated using four differently treated CoCrMo surfaces: (i) smoothly polished surface, (ii) electrochemical etched surface, (ii) textured surface with dimples, and (iv) parallel orientated-grooved surface. Results showed that the formed whiskers had a length ranging between 100 μm and 600 μm, and a diameter in the range of 2 μm to 5 μm. Electrochemically etched surfaces had better wettability and were favorably for growing whiskers. Surface morphology with (i) dimple textures or (ii) parallel grooves facilitated the effective control of the size and amount of the grown whiskers.