Bolin R B, Cheney B A, Simpliciano O A, Smith D J
J Lab Clin Med. 1981 Sep;98(3):342-51.
Separation of platelets by buoyant density centrifugation was periodically performed on platelet concentrates stored up to 96 hr at room temperature. By 72 hr, platelets were much lighter, depending on pH, platelet concentration, and volume of the bag. The mean proportion of platelets in the light fraction (fraction 1) shifted from 4.3% when the concentrate was fresh to 52.2% at 72 hr and 53.6% at 96 hr. The majority of platelets had densities that ranged from 1.034 to 1.088 gm/ml after storage, whereas densities ranged from 1.054 to 1.088 gm/ml in fresh cells. With storage, the light cells became larger than when they were fresh and were mostly balloon-shaped; the heavy cells became smaller but retained their normal shape. Regression analysis showed that density distribution was highly correlated to pH. Most of the changes occurred after 12 hr; those changes that occurred during the initial 12 hr were not related to pH of the platelet concentrate. The changes were related to storage conditions and may reflect injury to the cells. The use of buoyant density separation may be a useful tool to study storage mechanisms and provide a means of separating cells modified by storage stress.
对在室温下储存长达96小时的血小板浓缩物，定期通过浮力密度离心法分离血小板。到72小时时，血小板变得轻得多，这取决于pH值、血小板浓度和储存袋的体积。轻组分（第1组分）中血小板的平均比例从浓缩物新鲜时的4.3%，在72小时时变为52.2%，在96小时时变为53.6%。储存后，大多数血小板的密度范围为1.034至1.088克/毫升，而新鲜细胞的密度范围为1.054至1.088克/毫升。随着储存时间的延长，轻细胞比新鲜时变得更大，且大多呈气球状；重细胞变小但保持其正常形状。回归分析表明，密度分布与pH值高度相关。大多数变化发生在12小时后；最初12小时内发生的那些变化与血小板浓缩物的pH值无关。这些变化与储存条件有关，可能反映了细胞损伤。浮力密度分离的应用可能是研究储存机制的有用工具，并提供一种分离因储存应激而改变的细胞的方法。
