Blood apheresis technologies-a critical review on challenges towards efficient blood separation and treatment

Blood apheresis technologies are crucial during blood donation and toxin removal. Current purification methods such as leukocytapheresis, erythrocytapheresis, thrombocytapheresis and plasmapheresis primarily rely on centrifugation and membrane filtration to separate blood components. Although established and scaled-up, challenges related to the selectivity and long-term impact of these techniques on blood cells and their constituents remain. Shear generated during extraction may stress blood cells leading to cell damage and initiate the complement cascade causing platelet activation or triggering inflammatory responses. Emerging technologies, including microfluidics and selective adsorption present viable alternatives supporting more selective extraction pathways but extensively rely on novel manufacturing or material developments. This review critically assesses recent progress across apheresis technologies relating to advances in surface science and materials engineering to address operating challenges towards selective removal or extraction of blood components in traditional apheresis technologies such as centrifugation and membrane filtration.