γ-Ray irradiation of liposomes of polymerizable phospholipids containing octadeca-2,4-dienoyl groups and characterization of the irradiated liposomes
作者:Kazuhiro Akama、Yoshihiro Yano、Satoru Tokuyama、Fumio Hosoi、Hideki Omichi
DOI:10.1039/a908732j
日期:——
The synthesis of a variety of polymerizable phospholipids containing the octadeca-2,4-dienoyl moiety on 2-acyl chains and the characteristics of liposomes containing those phospholipids of the γ-irradiation are described. We synthesized three different polymerizable phosphocholines that have different 1-acyl chain lengths with the octadeca-2,4-dienoyl moiety on the 2-acyl chain: myristoyl (MODPC), palmitoyl (PODPC) and stearoyl (SODPC). The liposomes were prepared by extrusion through polycarbonate filters with a pore size of 0.2 µm, and were polymerized by γ-irradiation with various dose rates. The polymerization rate increased in the order SODPC > MODPC > PODPC. The mechanism of the polymerization of SODPC was the same as that of 1,2-bis-[(E,E)-octadeca-2,4-dienoyl]-sn-glycero-3-phosphocholine (DODPC), but differed from that of MODPC and PODPC. Freezeâthaw testing was used to evaluate the stability of the polymerizable liposomes. The MODPC liposome was more stable than other monofunctional liposomes. For similar irradiation, the polymerization behavior of the liposomes was significantly affected by the 1-acyl length.
本文描述了含有十八碳-2,4-二烯酰基团在2-酰基链上的多种可聚合磷脂的合成以及含有这些磷脂的脂质体在γ辐照下的特性。我们合成了三种不同类型的可聚合磷脂酰胆碱,它们具有不同长度的1-酰基链和2-酰基链上的十八碳-2,4-二烯酰基团:肉豆蔻酰(MODPC)、棕榈酰(PODPC)和硬脂酰(SODPC)。脂质体通过0.2微米孔径的聚碳酸酯滤器挤压制备,并通过不同剂量率的γ辐照进行聚合。聚合速率按SODPC > MODPC > PODPC的顺序增加。SODPC的聚合机制与1,2-双[(E,E)-十八碳-2,4-二烯酰]-sn-甘油-3-磷脂酰胆碱(DODPC)相同,但与MODPC和PODPC不同。通过冷冻-解冻测试评估了可聚合脂质体的稳定性。MODPC脂质体比其他单功能脂质体更稳定。对于类似的辐照,脂质体的聚合行为受到1-酰基长度的显著影响。