Fan Linlin, Sun Xuyang, Wang Xuelin, Wang Hongzhang, Liu Jing
Department of Biomedical Engineering, School of Medicine, Tsinghua University Beijing 100084 China
Technical Institute of Physics and Chemistry, Chinese Academy of Sciences Beijing 100190 China.
RSC Adv. 2019 Apr 29;9(23):13026-13032. doi: 10.1039/c9ra02286d. eCollection 2019 Apr 25.
Liquid metals (LMs) have recently emerged as a new class of promising multifunctional materials with attractive properties. They have excellent photothermal conversion efficiency, generating heat under near-infrared (NIR) laser irradiation. This work reports encapsulating LM droplets into poly(NIPAm--MBA) hydrogels (PNM) to achieve nanodispersed liquid metals in bulk polymeric hydrogels for NIR laser-responsive materials. LM droplets (∼530 nm) are produced by dispersing an alloy of gallium and indium (EGaIn) into glycerol. The LM-loaded PNM hydrogels (PNM/LM) exhibited excellent thermal-/NIR laser-responsive ability. In a water bath, the weight of the PNM/LM can decrease 92% at 50 °C. And the volume of PNM/LM can decrease 62% under NIR laser irradiation for 12 min. Because of its thermal-/NIR laser-responsive ability and porous three-dimensional (3D) networks, PNM/LM is very suitable for use as a drug carrier. We also prepared doxorubicin (DOX)-loaded PNM/LM hydrogels (PNM/LM/DOX) and demonstrated that the PNM/LM/DOX hydrogel can generate heat and raise its temperature under NIR laser irradiation. When the temperature becomes higher than the lower critical solution temperature (LCST), such a hydrogel would shrink immediately and extrude the DOX encapsulated in its networks simultaneously, then complete the controlled release of the pre-loaded drug. Further, an cytotoxicity test indicated the biocompatibility and feasibility as a chemophotothermal synergistic therapeutic of the present hydrogel. This NIR laser-responsive hydrogel fully exhibits its superiority as a drug carrier which promises great potential in future targeted controlled drug release.
液态金属（LMs）最近已成为一类具有吸引力的新型多功能材料，具有诱人的特性。它们具有出色的光热转换效率，在近红外（NIR）激光照射下会产生热量。这项工作报道了将液态金属液滴封装到聚（NIPAm-MBA）水凝胶（PNM）中，以在本体聚合物水凝胶中实现纳米分散的液态金属，用于近红外激光响应材料。通过将镓铟合金（EGaIn）分散到甘油中来制备液态金属液滴（约530nm）。负载液态金属的PNM水凝胶（PNM/LM）表现出出色的热/近红外激光响应能力。在水浴中，PNM/LM的重量在50°C时可减少92%。并且在近红外激光照射12分钟后，PNM/LM的体积可减少62%。由于其热/近红外激光响应能力和多孔三维（3D）网络，PNM/LM非常适合用作药物载体。我们还制备了负载阿霉素（DOX）的PNM/LM水凝胶（PNM/LM/DOX），并证明PNM/LM/DOX水凝胶在近红外激光照射下会产生热量并升高温度。当温度高于最低临界溶液温度（LCST）时，这种水凝胶会立即收缩并同时挤出包裹在其网络中的DOX，然后完成预加载药物的控释。此外，细胞毒性测试表明了本水凝胶作为化学光热协同疗法的生物相容性和可行性。这种近红外激光响应水凝胶充分展现了其作为药物载体的优越性，在未来靶向控释方面具有巨大潜力。
