A unit of whole blood drawn is separated into individual constituents or, rather, blood components. This is done by applying physical methods, such as centrifuge, filtering and similar.

A bag of whole blood can be used to prepare concentrated erythrocytes, concentrated platelets and fresh frozen plasma.



Every blood component requires special storage in a special preservative solution.

  • Erythrocytes or red blood cells are stored in special refrigerators at 4°C ± 2°C for up to 42 days.
  • Platelets (pathogen inactivated) are stored at 22°C ± 2°C for up to 7 days.
  • Plasma is deep frozen and stored at temperatures below -18 C for up to 3 months or at temperatures below -25°C for up to 3 years.

Processing procedures include procedures for identifying the blood group. Hence, AB0, RhD and Kell blood group antigens are identified for every unit of blood drawn. Upon the first two blood donations, extended testing for other antigens of the Rh system (C, c, E, e, etc.) is performed for each donor.



At the same time, blood is screened for infection markers that are transmitted by blood (HIV, hepatitis B and C viruses and syphilis). In case of unexpected test results, a blood donor is notified in confidence and the blood is discarded.