Bao J Z, Davis C C, Swicord M L
Department of Electrical Engineering, University of Maryland, College Park 20742.
Biophys J. 1994 Jun;66(6):2173-80. doi: 10.1016/S0006-3495(94)81013-6.
Complex dielectric constants of human erythrocyte suspensions over a frequency range from 45 MHz to 26.5 GHz and a temperature range from 5 to 40 degrees C have been determined with the open-ended coaxial probe technique using an automated vector network analyzer (HP 8510). The spectra show two separate major dispersions (beta and gamma) and a much smaller dispersion between them. The two major dispersions are analyzed with a dispersion equation containing two Cole-Cole functions by means of a complex nonlinear least squares technique. The parameters of the equation at different temperatures have been determined. The low frequency behavior of the spectra suggests that the dielectric constant of the cell membrane increases when the temperature is above 35 degrees C. The real part of the dielectric constant at approximately 3.4 GHz remains almost constant when the temperature changes. The dispersion shifts with temperature in the manner of a thermally activated process, and the thermal activation enthalpies for the beta- and gamma-dispersions are 9.87 +/- 0.42 kcal/mol and 4.80 +/- 0.06 kcal/mol, respectively.
利用自动矢量网络分析仪（惠普8510）的开口同轴探头技术，测定了人体红细胞悬液在45兆赫至26.5吉赫频率范围以及5至40摄氏度温度范围内的复介电常数。光谱显示出两个独立的主要色散（β和γ）以及它们之间一个小得多的色散。借助复非线性最小二乘法技术，用包含两个科尔 - 科尔函数的色散方程对这两个主要色散进行了分析。已确定该方程在不同温度下的参数。光谱的低频行为表明，当温度高于35摄氏度时，细胞膜的介电常数会增加。当温度变化时，在大约3.4吉赫处介电常数的实部几乎保持不变。色散以热激活过程的方式随温度变化，β色散和γ色散的热激活焓分别为9.87±0.42千卡/摩尔和4.80±0.06千卡/摩尔。
