Cole Parameters of Human Blood with Different Anticoagulants

摘要

Impedance spectroscopy of blood samples with Acid Citrate Dextrose, Ethylene Diamine Tetra-acetic Acid, Lithium Heparin and Sodium Citrate anticoagulants, taken from healthy male donors between ages 22-28, are performed in the frequency range 20Hz-1MHz, using the two probe method at room temperature. However, only high frequency data (100 kHz-1MHz) are used in fitting the Cole circle, where effects of electrode polarization are negligible. It is shown that this is acceptable since the characteristic frequency of the samples occurs around 1MHz. Mean values of plasma alone resistivities from 9 donors are 70 ± 1.3 Ω.cm: 79.2 ±1.3 Ω.cm: 72 ± 3.4 Ω.cm and 78.3 ± 1.2 (1cm and the extrapolated plasma resistivities from Maxwell-Fricke formulas at 0% hemato-crit are 58 Ω.cm, 59 Ω.cm 79 Ω.cm and 88 Ω.cm for EDTA, LH, SC and ACD respectively. At 100% hematocrit, the extracellular conductivity is zero and the extrapolated intracellular resistivities are 200 Ω.cm for EDTA; 214 Ω.cm for LH; 261 Ω.cm for SC and 176 Ω.cm for ACD. The rate of increase in extracellular resistance with hematocrit is higher with LH and EDTA. In the physiological range of hematocrit, Re is the highest with LH and lowest with SC; at 60% hematocrit LH samples are 34% higher than SC samples. The characteristic frequency, fc, changes with the type of anticoagulant; the frequency span at 50% hematocrit is from 0.8 MHz (LH) to 1.1 MHz (ACD). The angle of depression is highest with LH.