频域阻抗法研究细胞介电特性

Investigation on Dielectric Properties of Biological Cells with Impedance Technique in Frequency Domain

对生物细胞介电特性的研究是生物医学物理学公认的前沿重点课题之一。本文介绍如何采用宽频域交流阻抗技术研究细胞介电特性的原理和方法,以及在细胞介电谱的基础上,如何通过非线性数值计算建立细胞的数学模型和物理模型。本文以蛙骨骼肌细胞为例,在100Hz～100MHz范围内,应用阻抗分析仪测量了细胞交流阻抗,通过细胞介电谱、Cole-Cole图、介电耗损因子频率谱、介电损耗角正切频率谱等方式,分析了骨骼肌细胞介电特性的数据特征;最后使用Cole-Cole模型和椭圆壳介电理论,建立了骨骼肌细胞的数学模型和物理模型,为今后利用数理模型方法分析骨骼肌疲劳、骨骼肌萎缩等奠定了基础。

It is one of the acknowledged frontier research topics in biomedical physics to study the dielectric properties of biological cells. In the article, we present a principle and method of investigating the properties with the impedance technique in the broad-frequency domain, and introduce the way to establish a cell mathematical and physical model through nonlinear numerical calculation based on cell dielectric spectroscopy. Taking frog skeletal muscle as the illustration, we measured the AC impedance of the muscle cells with an impedance analyzer within the frequency range of 100 Hz～100 MHz, and analyzed the dielectric numerical characters of the cells by way of cell dielectric spectroscopy, the Cole-Cole plots, as well as the frequency spectroscopy of the dielectric loss factor and loss tangent. Finally we established a mathematical and physical model with the help of the dielectric ellipsoidal-shell model and Cole-Cole formula, hopefully laying a theoretical foundation for future analysis of skeletal muscle fatigue, malnutrition and atrophy with mathematical and physical models.