2.4.1. Sample Preparation

Whole blood samples were freshly collected from a 31-year-old male in sterile blood collection tubes (VACO MED, Cairo, Egypt) with sodium citrate as an anticoagulant. Sodium citrate was chosen for being relatively less destructive to blood cells as compared to EDT [47]. A complete blood count (CBC) was performed, and 51% hematocrit was measured for the donor’s blood sample. The whole blood sample was diluted to reduce the cell-to-cell interaction due to the high concentration of RBCs in the blood. A sample tube was prepared by mixing the whole blood in DI water with a ratio of 1:51, respectively. Therefore, the resulting diluted sample was 1% hematocrit. To prepare 2% and 3% hematocrit blood samples, the whole blood was diluted in DI water with ratios of 1:25.5 and 1:17, respectively. Diluting using DI water causes lysis of RBCs. When the target is separation of RBCs, it is recommended to use saline solutions for dilution to avoid any lysis of RBCs.