Temperature-responsive and Biodegradable Polymeric Micelles as drug carrier

温度响应且可生物降解的聚合物胶束作为药物载体

基本信息

批准号：
08672569
负责人：
AOYAGI Takao
金额：
$ 1.41万
依托单位：
Tokyo Women's Medical University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1998
项目状态：
已结题

项目摘要

Site-specific drug delivery has been markedly focused on the enhancement of pharmacological efficacy and reduction of side effects. The polymeric micelle shows very high stability in aqueous media due to its low critical micelle concentration. In this project, we attemped to fabricate sitespecific drug carriers using temperature-responsive polymeric micelle. Namely, novel type of polymeric micelle were prepared from N-isopropylacrylamide (IPAAm)-D,L-lactide(DLLA) block copolymer. PIPAAm is known to be a thermo-responsive polymer which has lower critical solution temperature (LCST, 32ﾟC). Below the LCST, PIPAAm shows the hydrophilicity and is soluble in aqueous media due to strong hydration and it is insoluble due to dehydration above the LCST.This phase transition takes place in narrow temperature range. Moreover, poly(D,L-lactide) is well-known as a biodegradable polymer. The corresponding block copolymer formed the micellar structure with core (PDLLA)-shell (PIPAAm) below LCST.On ther other hand, abovel LCST the polymeric micelles fomed aggregation. This phenomena was completely reversible. It was expected to induce selective accumulation controlled by temperature modulation. Namely, in a body, the thermo-responsive polymeric micelle would accumulate at the locally heated place. This finding surely contributes to site-specific drug delivery.

特定部位的药物输送已明显地集中在药物有效性和副作用降低的增强上。由于其低临界微孔浓度，聚合物微紫色在水性培养基中显示出很高的稳定性。在这个项目中，我们试图使用温度响应性聚合物微旋球来制造特定地点的药物载体。也就是说，从N-异丙烯酰胺（IPAAM）-D，L-丙二醇（DLLA）块共聚物制备了新型的聚合物微紫色类型。 PIPAAM是一种热响应聚合物，其临界溶液温度较低（LCST，32℃）。在LCST下方，PIPAAM显示出亲水性，并且由于强大的水合而在水性培养基中固体，并且由于LCST上方的脱水而无法溶解。这种相变发生在狭窄的温度范围内。此外，聚（d，l-酰基）众所周知是可生物降解的聚合物。相应的块共聚物形成了胶束结构，另一方面是LCST。在LCST下方，在聚合物胶束摄像机摄像机聚集中添加了LCST。这种现象是完全可逆的。预计将诱导通过温度调制控制的选择性积累。也就是说，在体内，热响应的聚合物胶束会在局部加热的地方进行丙烯酸胶束。这一发现肯定有助于特定部位的药物输送。