RAFT聚乙烯的合成和表征
Makoto Obata1, Shiho Hirohara2
1Graduate Faculty of Interdisciplinary Research, University of Yamanashi, 4-4-37 Takeda, Kofu 400-8510, Japan.
Materials (Basel, Switzerland)
|June 10, 2023
概括
开发了新的聚合物微粒,用于在光动力学疗法 (PDT) 中提供光敏剂. 该研究发现,中性疏水和pH响应单位对于有效的光敏感剂封装和输送至关重要.
科学领域:
- 聚合物化学 聚合物化学
- 生物医学工程 生物医学工程
- 光动力学疗法 光动力学疗法
背景情况:
- 聚合物微粒是用于光动力疗法 (PDT) 的疏水性光敏剂的有效药物递送系统.
- 之前的工作确立了适应pH的聚合物微粒 (P(St-co-DMAEA) -b-PPEGA) 用于酸 (ZnPc) 的输送.
研究的目的:
- 为了合成和评估新的pH响应的聚合物微粒,P(BA-co-DMAEA) -b-PPEGA,用于光敏感剂的输送.
- 为了研究中性疏水性单元在这些微粒的表现中的作用.
- 为了比较不同光敏感剂 (TFPC,TFPP,PPIX,ZnPc) 在发育的细胞中封装时的疗效.
主要方法:
- 通过可逆添加和碎片化链转移 (RAFT) 聚合合成P(BA-co-DMAEA) -b-PPEGA.
- 通过监测不同pH值的尺寸分布变化来表征微粒的pH响应.
- 各种光敏感剂的封装和封装效率的评估.
- 使用RGK-1细胞系对负载细胞对自由光敏化剂的光细胞毒性的评估.
主要成果:
- P(BA-co-DMAEA) -b-PPEGA小粒表现出pH响应的行为,在pH值5.0时尺寸分布发生变化.
- 封装效率因特定的光敏剂而异.
- 与RGK-1细胞中的自由TFPC相比,TFPC载荷的细胞显示出增强的光细胞毒性.
- 用ZnPc加载的小粒也表现出改善的光细胞毒性,但效果不如用P(St-co-DMAEA) -b-PPEGA.制成的小粒.
结论:
- 中性疏水和pH响应单元的设计对于优化光敏剂封装和通过聚合物微粒传递至关重要.
- 疏水性单元的选择会影响光敏剂输送系统的整体有效性.
- 需要进一步的研究,以微调聚合物微粒组成,以提高PDT应用.
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