Changes in Surface-Charge Density of Blood Cells After Sudden Unexpected Death

Abstract

The objective of the investigation was evaluation of postmortem changes of electric charge of human erythrocyte and thrombocyte membranes after sudden unexpected death. The surface charge density values were determined on the basis of the electrophoretic mobility measurements of the cells carried out at various pHs of electrolyte solution. The interactions between both erythrocyte and thrombocyte membranes and electrolyte ions were studied. Values of parameters characterizing the membrane—that is, the total surface concentrations of both acidic and basic groups and their association constants with solution ions—were calculated on the basis of a four-equilibria mathematical model. The model was validated by comparison of these values to experimental data. We established that examined electric properties of the cell membranes are affected by sudden unexpected death. Postmortem processes occurring in the cell membranes can lead to disorders of existing equilibria, which in turn result in changes in values of all the above-mentioned parameters.

The attachment of <i>Staphylococcus epidermidis</i> on the surface of a carbon paste electrode at various positive potentials: The effect of pH, incubation time, and solid-medium type

“…Although we did not provide the enumeration of dead cells of S. epidermidis, we found that thermally inactivated yeast cells significantly increased I 0(extent) and I E(extent) values compare with those for viable cells [14]. These findings also corresponded with the study of the postmortem changes in the surface charge of the membranes of the human erythrocytes [21]. Although not fully comparable with our research, they demonstrated the increase of charges (depending on pH) after sudden unexpected death of cells.…”

The Effect of Fatal Carbon Monoxide Poisoning on the Surface Charge of Blood Cells

“…Due to the lack of literature data concerning the influence of exogenous CO on the electrical properties of biological membranes, we examined changes in the surface charge of blood cells after fatal CO poisoning. This work continues a systematic study of the electrical properties of human erythrocyte and thrombocyte membranes realized by Figaszewski and coworkers (Petelska et al 2012; Kotyńska et al 2012). The experiment was performed using a microelectrophoresis method, which is one of the basic analytical tools for biological studies.…”

“…In basic solutions an increase in negative charge after fatal CO poisoning in comparison to control erythrocytes and a small shift of the isoelectric point of the membrane to high pH values were observed. The membrane surface charge density values in fatal CO poisoning presented here were compared with the membrane surface charge density values after sudden unexpected death obtained by us previously (Kotyńska et al 2012). As can be seen, the values shown in Fig.…”

The Effect of Fatal Carbon Monoxide Poisoning on the Equilibria Between Cell Membranes and the Electrolyte Solution

“…This work continues the systematic study of electrical properties of human erythrocytes and thrombocytes membranes realized by Figaszewski and co-workers (Petelska et al 2012 ; Kotyńska et al 2012 ; Szeremeta et al 2013 ). In our previous paper (Szeremeta et al 2013 ), we presented changes of the surface charge of blood cells after fatal carbon monoxide poisoning obtained only on the experimental way.…”

“…Dependence of surface charge density of cell membrane on the pH of electrolyte solution can be described with help of the four-equilibrium model. The mathematical formulation of this model was proposed by Dobrzyńska and co-workers and presented in full details in the papers elsewhere (Dobrzyńska et al 2006 ; Kotyńska et al 2012 ). Assumptions of the model are described by Eqs.…”