Introduction
Peripheral blood mononuclear cells (PBMCs) are often processed to separate from whole blood by density gradient centrifugation. Those cells are consist of lymphocytes (T cells, B cells, NK cells) and monocytes, commonly used in the field of immunology, cell therapy, infectious disease, and vaccine development. Monitoring and analyzing the viability and concentration of PBMC is crucial for clinical laboratories, basic medical science research, and immune cell production.