Superfast Near-Infrared Light-Driven Polymer Multilayer Rockets
Superfast Near-Infrared Light-Driven Polymer Multilayer Rockets
复制标题
超快近红外光驱动聚合物多层火箭
DOI：
10.1002/smll.201502605
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发表时间：
2016-02-03
期刊：
影响因子：
13.3
通讯作者：
He, Qiang
中科院分区：
文献类型：
--
作者：
Wu, Zhiguang;Si, Tieyan;He, Qiang
在这里，我们提出了一种聚合物管状火箭，用金纳米壳（AuNS）功能化，以高达160 µm s− 1的速度移动。AuNS在NIR区域中的较强等离子体共振吸收在非对称AuNS的内表面和外表面上产生局部温度梯度。火箭内表面较高的热梯度和火箭的非对称结构导致热泳力沿着火箭长轴方向的差异，进而驱动火箭向前端小开口方向运动。火箭可以执行近红外触发的“开/关”运动在远程控制的方式，并有效地移动与强大的方向性在细胞培养基中，这是至关重要的实际生物医学应用。[42简言之，通过逐层（LbL）技术将带负电荷的聚（苯乙烯磺酸）（PSS）和带正电荷的聚（烯丙基胺盐酸盐）（PAH）交替组装到纳米多孔聚碳酸酯膜的内壁中来制备火箭的框架。柠檬酸盐稳定的金纳米粒子（AuNPs），直径约为20 nm，然后组装到（PSS/PAH）20改性的多孔膜通过静电相互作用。通过种子生长过程在火箭中形成AuNS，最后在CH 2 Cl 2中溶解模板后释放出分散良好的（PSS/PAH）2 0 AuNS火箭。图1 B、C中的透射电子显微镜（TEM）和扫描电子显微镜（SEM）图像都显示了所得（PSS/PAH）20 AuNS火箭的不对称圆锥几何形状，如我们先前报道的那样。[42]长度为10-12微米，火箭的两个开口直径分别为5和5.5微米。图1 B中火箭的暗区可以归因于AuNS的成功形成。图1C中相应的能量色散X射线（EDX）映射分析进一步验证了（PSS/PAH）20 AuNS火箭中AuNS的存在。图1D中的UV-vis光谱揭示了（PSS/PAH）20 AuNS火箭在λ 780 nm处的最大吸收，这对于NIR区域中的光热效应是重要的。用于火箭推进的近红外照明装置的布局如图S1（支持信息）所示。激光束通过物镜透镜垂直照射到样品平面上，并固定在约15 μm的直径。从视频1（支持信息）捕获的图1 E中的延时图像说明了
Here, we present a polymeric tubular rocket, functionalized with gold nanoshells (AuNSs) that moves at a speed of up to 160 µm s− 1. The stronger plasma resonance absorption of AuNSs in the NIR region creates local temperature gradients on the inner and outer surfaces of asymmetric AuNSs.[39–41] Both the higher thermal gradient on the inner surface and the asymmetric structure of the rockets result in the difference of thermophoretic forces along the elongated axis of rockets, which in turn drives the rockets to move toward the direction of the front small-opening. The rockets can perform NIR-triggered “on/off” motion in a remotely controlled manner and efficiently move with robust directionality in cell culture media, which is crucial for practical biomedical applications.The fabrication strategy is schematically illustrated in Figure 1A, according to our previously developed method.[42, 43] Briefly, the framework of the rockets is prepared by alternatively assembling negatively charged poly (styrenesulfonic acid)(PSS) and positively charged poly (allylamine hyhrochloride)(PAH) into the inner walls of nanoporous polycarbonate membranes by layer-by-layer (LbL) technique. The citrate-stabilized gold nanoparticles (AuNPs), with diameters of about 20 nm, are then assembled into the (PSS/PAH) 20-modified porous membranes via electrostatic interactions. The AuNSs inside the rockets are formed through a seeding-growth procedure and finally the well-dispersed (PSS/PAH) 20AuNS rockets are released after the dissolution of templates in CH 2Cl 2. Both the transmission electron microscope (TEM) and the scanning electron microscopy (SEM) images in Figure 1 B, C show the asymmetric conical geometry of the resulting (PSS/PAH) 20AuNS rockets like our previously reported.[42] The length is≈ 10–12 µm, and two opening diameters of the rocket are 5 and 5.5 µm, respectively. The dark region of the rockets in Figure 1 B can be ascribed to the successful formation of AuNSs. The corresponding energy-dispersive X-ray (EDX) mapping analysis in Figure 1 C further verifies the presence of AuNS in the (PSS/PAH) 20AuNS rocket. The UV–vis spectrum in Figure 1 D reveals the maximum absorption of the (PSS/PAH) 20AuNS rockets at≈ 780 nm, which is important for the photothermal effect in NIR region. The layout of NIR illumination setup for the propulsion of rockets is illustrated in Figure S1 (Supporting Information). A laser beam is vertically irradiated onto the sample plane through an objective lens and is fixed in a diameter of about 15 µm. The time-lapse images in Figure 1 E, captured from Video 1 (Supporting Information), illustrate the