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Nanoindentation technology as a powerful tool to test the mechanical properties of biological materials micron scale by, more and more attention. Load resolution of its 15N maximum load range 1nN and 0.0002nm displacement resolution, making it the connection made to the atomic force microscope (AFM) nano-scale mechanical properties testing and universal testing machine (UTM) made to the macro-scale mechanical properties test the bridge. Biological materials nanoindentation experiments, however, has many different from conventional materials microscale mechanical properties test, for example, complex sample preparation, many experimental factors, data analysis difficult, and so on, so that the mechanical properties of biological materials microscale test many urgent solve the problem. Microscale mechanical properties of biological materials, mainly from the following aspects were studied: (1) as a specimen surface treatment demanding experimental methods, biological sample preparation technique is its microscale mechanical properties testing factor. The three conventional biological sample preparation technique (blood smear method, direct bonding, cold damascene method), experimental studies found that the conventional method causes the sample exposed to the air gradual evaporation of water, is not conducive to maintaining biological The biological activity of the sample, reducing the credibility of the experiment. Development of new biological material preparation techniques solve these problems and the associated sample table, and the mechanical properties of the biological sample can be measured in solution, and effectively preventing the dislocation of the sample in the measurement. (2) the structure and function of biological material in nanoindentation experiments reflect different from the conventional mechanical characteristics of the materials, the correct analysis and reasonable explanation of the experimental results of the biological sample need to take full account of this problem. Study the biological material and four related structure and function, i.e. visco-elastic, non-uniform anisotropy and adhesion, binding experiments that its influence on the nano-indentation experiments, and for the subsequent experiments in the method and control find a basis for the choice of parameters. (3) the articular cartilage Open surgery how to choose the appropriate level of protection solution to maintain cartilage inherent performance, is a hot issue in the medical. In this paper, new biological sample testing methods combined with homemade sample stage quantitative measurement of the chitosan solution, saline under the protection of the mechanical properties of articular cartilage, compared with distilled water protection group, applied mechanics studied this problem . The study results showed that the chitosan solution and saline has the effect of maintaining the existing mechanical properties of articular cartilage, and only with distilled water samples moisturizing, cartilage mechanical properties change. The experimental results in line with expectations envisaged for further biological materials microscale mechanical properties, providing a suitable method and theory, and provide a reference for numerical computation.
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