Liu Xiaojia, Chen Wenjun, Zhao Dongfang, Liu Xiaoxia, Wang Yong, Chen Yuduo, Ma Xing
Sauvage Laboratory for Smart Materials, School of Materials Science and Engineering, Harbin Institute of Technology (Shenzhen), Guangdong, Shenzhen 518055, China.
Shenzhen Bay Laboratory, No. 9 Duxue Road, Shenzhen 518055, China.
ACS Nano. 2022 Jul 26;16(7):10354-10363. doi: 10.1021/acsnano.2c00401. Epub 2022 Jul 11.
Achieving molecular sample capture at micro/nanoscales while integrating functions of controllable loading and real-time monitoring of cargo molecules is of great significance in the development of intelligent micro/nanorobots. Herein, we prepare a temperature-responsive microsampling nanorobot by encapsulating metal (Au) nanodots inside hollow mesoporous silica nanoparticles and grafting a temperature-responsive polymer, poly(-isopropylacrylamide), on their external surface. The molecular gate of nanochannels accessing the internal hollow reservoir can be switched between "open" and "closed" states by regulating the temperature, allowing on-demand loading and releasing of small molecules. The internally embedded surface-enhanced Raman scattering hotspots of gold nanodots can serve as sensing probes for real-time detection of the molecular cargo load inside the hollow nanorobots. Furthermore, we demonstrate temperature-dependent self-propulsion behavior of the nanorobots driven by enzymatic reactions. The active motion behavior can favorably regulate the loading efficiency of molecular cargos. In addition, by further introducing the magnetic component Ni, the nanorobots can accomplish effective transportation of cargo molecules by magnetic guidance under real-time Raman monitoring. The current strategy is expected to provide a manipulable nanorobot platform for precise biomedical sampling, which holds promising potential for disease diagnosis or controlled drug delivery in precision medicine.
在实现微/纳尺度下分子样本捕获的同时，集成可控装载和货物分子实时监测功能，对智能微/纳米机器人的发展具有重要意义。在此，我们通过将金属（金）纳米点封装在中空介孔二氧化硅纳米颗粒内部，并在其外表面接枝温度响应聚合物聚（N-异丙基丙烯酰胺），制备了一种温度响应型微采样纳米机器人。通过调节温度，进入内部中空储库的纳米通道的分子门可以在“打开”和“关闭”状态之间切换，从而实现小分子的按需装载和释放。内部嵌入的金纳米点的表面增强拉曼散射热点可作为传感探针，用于实时检测中空纳米机器人内部的分子货物负载。此外，我们展示了由酶促反应驱动的纳米机器人的温度依赖性自推进行为。这种主动运动行为可以有利地调节分子货物的装载效率。此外，通过进一步引入磁性成分镍，纳米机器人可以在实时拉曼监测下通过磁引导完成货物分子的有效运输。当前策略有望为精确生物医学采样提供一个可操控的纳米机器人平台，在精准医学中的疾病诊断或可控药物递送方面具有广阔的应用前景。
