Increase in plasma lipofuscin levels of stored blood.

Venous blood samples from Caucasian men, collected in citrate-phosphate-dextrose anticoagulant and stored in plastic or in glass containers for 10-, 20- and 30-day periods at 4 degrees C, showed increasing levels of plasma lipofuscin (PL) substances. These levels were measured as the intensities of the 340-nm excitation maximum and the 440-nm fluorescence maximum of PL, using a fluorescence spectrophotometer. No increase in PL level was observed in plasma samples separated before storage. These observations suggest that the free-radical activity of PL substances may confer toxic properties to stored blood used in large transfusions, and that stored blood may lose part of its osmotic, hemostatic, immunologic, and other physiologic functions as more plasma proteins are converted into lipofuscin.