采用动态光散射法研究肝素在溶液中的聚集态以及超声处理对肝素在溶液中的聚集态和稳定性的影响,发现:肝素在水溶液中以多分子交联的聚集态形式存在,肝素浓度越高,聚集体粒径越大;加入NaCl 可在一定程度上减小肝素聚集体的粒径,但不能从根本上消除聚集体;施加超声可显著减少肝素在溶液中的聚集,在低功率百分数短时超声(30%,3min)作用下,100 ~1000nm 粒径的肝素聚集体减少,转化为1 ~10nm 粒径的肝素单体,表明超声处理是一种有效减弱肝素聚集的方法;采用100 nm 孔径的膜进行分离和冷冻干燥可得到粒径为1 ~10nm 的解聚肝素粉末;解聚肝素溶液常温下放置64 h 后不会重新聚集,具有较强的稳定性.

In this paper, dynamic light scattering is employed to investigate the aggregation of heparin in aqueoussolution and to reveal the influence of ultrasonic treatment on the aggregation and stability of heparin. The resultsshow that heparin exists in aqueous solution in the form of aggregated species via multiple-molecule cross-linking,with the particle size of the aggregates increasing with the heparin concentration, that the aggregates cannot be com-pletely eliminated though the addition of sodium chloride leads to a reduction of aggregates diameter in a certain de-gree, and that ultrasonic treatment significantly restrains the heparin aggregation. When ultrasound with 30% ofpower percentage is applied for 3min, the aggregates with the diameter of 1001000 nm change into heparin mono-mers with the diameter of 110 nm, which means that ultrasonic treatment is effective in restraining the heparinaggregation. Moreover, disaggregated heparin powder with the diameter of 110nm can be obtained by the filtrationwith 100nm membrane and subsequent freeze drying. The disaggregated heparin remains stable after the storage formore than 64h at room temperatures.