Quantitative Measurement of the Erythrocyte Sedimentation Based on Electrical Impedance Spectroscopy With Modified HANAI Theory and the Multi-Frequency Parameter Xc

Conventional erythrocyte sedimentation measurements are time consuming, and still having difficulties to obtain intermediate status. In this study, the modified HANAI theory and multi-frequency parameters are proposed to quantitatively monitor the erythrocyte sedimentation based on electrical impedance spectroscopy (EIS). Different with previous studies, the multi-frequency parameter and T-shape container are utilized and analyzed. Results exhibit that the impedance of blood is greatly influenced by erythrocyte sedimentation, and the EIS measurement for erythrocyte sedimentation with the T-shape type container is a good linear relationship of the multi-frequency parameter reactance
${X}_{c}$
and the sedimentation ratio
${R}_{se}$
compared with the parallel-shape type container. The linear relationship could be expressed as
${X}_{c}=-0.110{R}_{se}$
–1.347 with a correlation coefficient of
${R}^{2}=0.963$
. Additionally, the top point reactance
${X}_{c}$
is found to keep a great linear relationship with plasma height
${h}$
in standard Westergren tube as
${X}_{c}=-0.646\text{h}$
–1.996 with an excellent
${R}^{2}=0.967$
. FEM and modified HANAI calculations suggest that, the hematocrit (HCT) is responsible for the linear relationship. This study adopts a new structure detection method for the real-time monitoring of erythrocyte sedimentation with smaller sample volume, less manual manipulations and automation, which has certain scientific research and application value.