用于生物医学应用的无线磁性传感器。
Wireless, magnetic-based sensors for biomedical applications.
作者信息
Ong Keat Ghee, Tan Ee Lim, Pereles Brandon, Horton Brock
机构信息
Department of Biomedical Engineering, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931, USA.
出版信息
Annu Int Conf IEEE Eng Med Biol Soc. 2009;2009:5436-9. doi: 10.1109/IEMBS.2009.5332475.
Wireless magnetic sensor technologies are gaining popularity in biomedical community due to their remote query nature, which allows them to be used as long-term implantable sensors. Some of these sensors are also low cost so they are suitable for use on a disposable basis. In this paper, two wireless magnetic sensors are described: the magnetoelastic sensor and the magneto-harmonic sensor. Magnetoelastic sensors are made of magnetoelastic materials that when under an AC magnetic field excitation, vibrate and resonate at their resonant frequencies. Since the resonant frequency of a magnetoelastic sensor is proportional to the mass or viscosity of the surrounding material, it has been used to detect chemical and biological targets by incorporating coatings that change mass/elasticity in response to the parameters of interest. Conversely, magneto-harmonic sensors detect parameters of interest by monitoring the change in the pattern or amplitude of the magnetic higher-order harmonic fields. Typically, a magneto-harmonic sensor consists of a magnetically soft material (sensing element) and a permanent magnet (biasing element). When energized by an AC magnetic field, the sensing element generates higher-order magnetic fields that change with the biasing field from the biasing element. By designing the sensor so the separation distance between these two elements varies with the parameters of interest, the magneto-harmonic sensor has been used for remote measurement of pressure and stress. This paper presents the operating principles and biomedical applications of these sensors.
无线磁传感器技术因其远程查询特性在生物医学领域越来越受欢迎,这使得它们能够用作长期可植入传感器。其中一些传感器成本也很低,因此适合一次性使用。本文介绍了两种无线磁传感器:磁弹性传感器和磁谐波传感器。磁弹性传感器由磁弹性材料制成,当在交流磁场激励下时,会在其共振频率下振动和共振。由于磁弹性传感器的共振频率与周围材料的质量或粘度成正比,因此通过结合能响应感兴趣参数而改变质量/弹性的涂层,它已被用于检测化学和生物目标。相反,磁谐波传感器通过监测磁高阶谐波场的模式或幅度变化来检测感兴趣的参数。通常,磁谐波传感器由磁性软材料(传感元件)和永久磁铁(偏置元件)组成。当由交流磁场激励时,传感元件会产生随偏置元件的偏置场而变化的高阶磁场。通过设计传感器,使这两个元件之间的分离距离随感兴趣的参数而变化,磁谐波传感器已被用于压力和应力的远程测量。本文介绍了这些传感器的工作原理和生物医学应用。