The study of changes of biophysical properties of red blood cells in storage in erythrocyte-containing solutions using atomic force microscopy

Currently the departments of quality control of blood centers evaluate the suitability for clinical use of erythrocyte-containing solutions indirectly by routine methods of the determination of hemoglobin concentration, hematocrit level, or hemolysis at the end of the period of storing. These methods can not directly characterize the state of membranes of preserved erythrocytes. The aim of the work is to study the changes of elasticity and surface potential of membranes of red blood cells of erythrocyte-containing solutions in storage for 35 days. Material and Methods. Two series of dry cytological preparations (smears) of erythrocytes have been investigated. The first group consisted of 8 samples of erythrocyte-containing solutions prepared on the day of preservation, and the second group included 20 samples prepared after the long term storage for 35 days at t=+4°C. Blood was stored in bags of «Baxter» company (USA) conserving with «CPDA-1». For atomic force microscopy five typical erythrocytes were selected and their elasticity was measured at 9 points of the membrane of each erythrocyte. Total number of measurements was 1296. Results. Average value of Young's modulus of the first group of samples was 1,81±0,02 (M±m) KPa. The second group showed 3,22±0,02 KPa statistically higher (p