Measurement Conditions of Surface Membrane Zeta Potential for Young and Old RBCs

Abstract

The surface electrical characteristics of RBCs are closely related to its structural functions,and the Zeta potential is the crucial parameter when measuring the RBC's membrane surface charge.Owing to the uncertainty of the difference between young and old RBC's surface membrane Zeta potential,in this study,Percoll density gradient separation method was used to separate the young and old RBCs.By comparing the cell morphology and the ionic strength of suspension solution,it was pointed out that the RBC's surface Zeta potential was found to be influenced by the shape of the cells.RBCs would become echinocytes if the cell suspension solution is not suitable,the surface membrane Zeta potential would be also decreased at the same time.Secondly,the RBC's surface Zeta potential was inversely proportional to the ionic strength of suspension solution.Using 0.0145 mol/L NaCl + 0.026 mol/L glucose as the suspension solution,it was found that the Zeta potential of the young RBC was(-32.46 ± 1.24) mV,and the old one was(-25.88 ± 1.39) mV.The negative potential of the old one was about 20% less than the young one,indicating that it enables accurate detection of the surface membrane Zeta potential of living RBCs.