基于NIPAm对聚（L-赖氨酸）的改性：一种pH依赖性低临界溶液温度（LCST）型热响应性可生物降解聚合物。

NIPAm-Based Modification of Poly(L-lysine): A pH-Dependent LCST-Type Thermo-Responsive Biodegradable Polymer.

作者信息

Stamou Aggeliki, Iatrou Hermis, Tsitsilianis Constantinos

机构信息

Department of Chemical Engineering, University of Patras, 26500 Patras, Greece.

Department of Chemistry, University of Athens, Panepistimiopolis, Zografou, 15771 Athens, Greece.

出版信息

Polymers (Basel). 2022 Feb 18;14(4):802. doi: 10.3390/polym14040802.

Polylysine is a biocompatible, biodegradable, water soluble polypeptide. Thanks to the pendant primary amines it bears, it is susceptible to modification reactions. In this work Poly(L-lysine) (PLL) was partially modified via the effortless free-catalysed aza-Michael addition reaction at room temperature by grafting N-isopropylacrylamide (NIPAm) moieties onto the amines. The resulting PLL-g-NIPAm exhibited LCST-type thermosensitivity. The LCST can be tuned by the NIPAm content incorporated in the macromolecules. Importantly, depending on the NIPAm content, LCST is highly dependent on pH and ionic strength due to ionization capability of the remaining free lysine residues. PLL-g-NIPAm constitutes a novel biodegradable LCST polymer that could be used as "smart" block in block copolymers and/or terpolymers, of any macromolecular architecture, to design pH/Temperature-responsive self-assemblies (nanocarriers and/or networks) for potential bio-applications.

聚赖氨酸是一种具有生物相容性、可生物降解的水溶性多肽。由于其带有侧链伯胺，它易于进行修饰反应。在这项工作中，聚（L-赖氨酸）（PLL）通过在室温下轻松的无催化剂氮杂迈克尔加成反应进行了部分修饰，即将N-异丙基丙烯酰胺（NIPAm）部分接枝到胺基上。所得的PLL-g-NIPAm表现出最低临界溶液温度（LCST）型热敏感性。LCST可以通过大分子中掺入的NIPAm含量进行调节。重要的是，取决于NIPAm含量，由于剩余游离赖氨酸残基的离子化能力，LCST高度依赖于pH值和离子强度。PLL-g-NIPAm构成了一种新型的可生物降解的LCST聚合物，可作为任何大分子结构的嵌段共聚物和/或三元共聚物中的“智能”嵌段，用于设计pH/温度响应性自组装体（纳米载体和/或网络）以用于潜在的生物应用。