Golibersuch D C
Biophys J. 1973 Mar;13(3):265-80. doi: 10.1016/S0006-3495(73)85984-3.
The resistance pulse detector (Coulter counter) has been widely applied to the problem of determining the volumes of insulating particles in electrolyte solutions. This technique is based on the simple relationship, DeltaR/R = fv/V, between the fractional resistance change DeltaR/R and the ratio of particle volume v to pore volume V. The proportionality constant f is a function of particle shape and orientation. Direct observation of the expected resistance anisotropies for aspherical particles is reported here. As predicted by simple hydrodynamic theory each individual resistance pulse has a periodically varying amplitude as it traverses a long pore in the shear field of Poiseuille flow. Characteristics of the particle motion allow improved volume distribution determinations by properly accounting for the shape factor. Application is made to normal human erythrocytes and a gaussian volume distribution with a coefficient of variation approximately 19% is found. The electrical shape effect for erythrocytes is consistent with an oblate ellipsoidal particle with a diameter-to-thickness ratio of 4. Analysis of the data indicates that the convergent entrance flow orients the cells so that they enter the pore with their axis of symmetry perpendicular to the pore axis.
电阻脉冲检测器（库尔特计数器）已被广泛应用于测定电解质溶液中绝缘颗粒体积的问题。该技术基于分数电阻变化ΔR/R与颗粒体积v与孔隙体积V之比之间的简单关系，即ΔR/R = fv/V。比例常数f是颗粒形状和取向的函数。本文报道了对非球形颗粒预期电阻各向异性的直接观察。正如简单流体动力学理论所预测的那样，每个单独的电阻脉冲在泊肃叶流的剪切场中穿过长孔隙时，其幅度会周期性变化。通过适当考虑形状因子，颗粒运动的特性有助于改进体积分布的测定。将其应用于正常人红细胞，发现其高斯体积分布的变异系数约为19%。红细胞的电形状效应与直径与厚度比为4的扁椭球形颗粒一致。数据分析表明，收敛的入口流使细胞定向，从而使它们以对称轴垂直于孔隙轴的方式进入孔隙。
