Thermally Induced Switch of Coupling Reaction Using the Morphological Change of a Thermoresponsive Polymer on a Reactive Heteroarmed Nanoparticle
Thermally Induced Switch of Coupling Reaction Using the Morphological Change of a Thermoresponsive Polymer on a Reactive Heteroarmed Nanoparticle
复制标题
利用反应性杂臂纳米颗粒上热响应聚合物的形态变化进行偶联反应的热诱导开关
DOI：
10.1021/acsami.0c12875
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发表时间：
2020
影响因子：
9.5
通讯作者：
Ito Yoshihiro
中科院分区：
文献类型：
--
作者：
Park So Jung;Akimoto Jun;Sakakibara Naoki;Kobatake Eiry;Ito Yoshihiro
在研制复杂的水凝胶时，对交联反应的控制是必不可少的。在本研究中，设计了一种异臂热响应（TR）纳米颗粒，以研究引入纳米颗粒的官能团控制反应性的机制。利用温度诱导的TR聚合物形态变化抑制了偶联反应。将具有TR段和亲水性段的两亲嵌段共聚物与琥珀酰亚胺反应官能团共组装，制备了异臂TR纳米粒子。纳米颗粒上较长的TR链覆盖了琥珀酰亚胺基团，抑制了与外部纳米颗粒上伯胺的反应。相反，由于TR聚合物的形态改变，使得琥珀酰亚胺基暴露在颗粒表面，从而在高温下促进了偶联反应，在纳米颗粒之间形成了化学交联结构。此外，热控制的化学反应调节凝胶化的起始使用高浓度的纳米颗粒溶液。异臂TR纳米颗粒通过精确控制反应，为临床应用（如栓塞剂）提供了巨大的实用优势。
Control of the cross-linking reaction is imperative when developing a sophisticatedin situforming hydrogel in the body. In this study, a heteroarmed thermoresponsive (TR) nanoparticle was designed to investigate the mechanism of controlling reactivity of the functional groups introduced into the nanoparticles. The coupling reaction was suppressed/proceeded by utilizing temperature-induced morphological changes of the TR polymer. The heteroarmed TR nanoparticle was prepared by the coassembly of amphiphilic block copolymers possessing both a TR segment and hydrophilic segment with reactive functional groups of succinimide. The longer TR chain on the nanoparticle covered the succinimide group and suppressed the reaction with the primary amine on the external nanoparticle. In contrast, the coupling reaction was promoted at a high temperature to create the chemical cross-linking structure between the nanoparticles because of the exposure of the succinimide group on the surface of the particle as a consequence of the morphological change of the TR polymer. In addition, the thermally controlled chemical reaction modulated initiation of the gelation using a highly concentrated nanoparticle solution. The heteroarmed TR nanoparticle offers great practical advantages for clinical uses, such as embolization agents, through precise control of the reaction.