Changes in red blood cell membrane phosphate concentration during blood bank storage

The change in red blood cell membrane phosphate concentration of standard CPD whole blood stored in Fenwal blood bags at 4 C was measured daily for two weeks. Membrane phosphate concentrations increased rapidly when stored pH fell to 6.95. At the same time, the rate of K+ leakage from the cells increased, and transport of inorganic phosphate across the membrane decreased. It is concluded that gross uptake of phosphorus by the red blood cell membrane during blood bank storage may be in part responsible for physical changes in the membrane.