湿骨内压电电压的测试技术  

Technique for measuring piezo-voltages of wet bone

作　　者：徐莲云[1] 侯振德[1] 富东慧[1] 王轶涵[1] 

机构地区：[1]天津大学机械工程学院力学系,天津300072

出　　处：《医用生物力学》2013年第5期533-537,共5页Journal of Medical Biomechanics

基　　金：国家青年科学基金项目(11102129)

摘　　要：目的解决测量湿骨内压电效应的方法,实现湿骨内压电效应的测量。方法设计湿骨压电电压测试系统,采用铂铱电极测取压电信号,并利用超高输入阻抗的生物放大器放大压电信号;由于液体中几乎没有电流流动,即使电极不接触骨试样也可以测量到试样两侧的压电电压。结果在梯形波加载方式下测量到了电压曲线,并实验证明所测结果为骨试样的压电曲线。试验测量6个骨试样,结果显示湿骨压电电压只有在动态加卸载时才能表现出来,该现象与干骨压电特征相符合。结论采用铂铱电极测取压电信号和超高输入阻抗的生物放大器实现了湿骨内压电效应的测量。压力加载至9 N时的试样压电电压峰值在-0.75～-1.69 mV。本研究有助于进一步探索骨生长与电信号的关系,最终为临床骨愈合的研究提供理论依据。Objective To develop a method for measuring the piezoelectric effect in wet bone. Methods A pie- zoelectric voltage measurement system of wet bone was designed, which employed platinum/iridium electrodes to detect the piezo-voltages and an ultra-high input impedance bio-amplifier to amplify the piezo-voltage signals, respectively. Because there was nearly no electric current in the buffer solution, even the electrodes that did not contact the bone sample could detect the piezoelectric voltages at the side of two bone samples. Results Volt- age-time curves were obtained under the trapezoidal loading, and the results were confirmed to be piezoelectric voltages produced from bone by experiment. A total of 6 samples were tested. The measurement results showed that the piezo-voltages of wet bone were induced during the dynamic loading process, which was consistent with dry bone. Conclusions Measurement of the piezo-voltages in wet bone was developed by employing platinum/i- ridium electrodes for detecting the piezo-voltages and an ultra-high input impedance bio-amplifier for amplifying the piezo-voltage signals, and the validity of the test system was confirmed via experiments. The peak value of pi- ezo-voltage was between - 0.75 mV and - 1.69 mV under the loading peak value 9 N. The results are helpful to investigate the relationship between bone growth and electric signals, which provides the theoretical references for researches on bone healing in clinic.

关 键 词：湿骨 压电性 电压 电极 

分 类 号：R318.01[医药卫生—生物医学工程]