Size Reduction of 3D-polymer-coated Singlewalled Carbon Nanotubes by Ultracentrifugation
Size Reduction of 3D-polymer-coated Singlewalled Carbon Nanotubes by Ultracentrifugation
复制标题
通过超速离心减小 3D 聚合物涂覆的单壁碳纳米管的尺寸
DOI：
10.1039/c5nr05066a
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发表时间：
2015
期刊：
影响因子：
6.7
通讯作者：
N. Nakashima
中科院分区：
文献类型：
--
作者：
Y. Tsutsumi;T. Fujigaya;N. Nakashima
我们描述了一种新的单壁碳纳米管（SWNT）切割方法，该方法不会在管上引入任何结构缺陷;即，发现在600 000 g下，用聚乙烯形成的交联聚合物涂覆的SWNT的简单超离心（N-异丙基丙烯酰胺）（PNIPAM）或携带聚乙二醇的PNIPAM共聚物提供缩短的（<200 nm）SWNT，这是揭示了动态光散射（DLS）和原子力显微镜（AFM）测量。拉曼光谱和吸收光谱测试结果表明，切割后的单壁碳纳米管的石墨结构和光学性质，如近红外区的特征吸收和光致发光几乎没有变化。由于单壁碳纳米管上剩余的交联聚合物结构，所获得的缩短的单壁碳纳米管分别溶解在水和缓冲溶液中。本发明的方法非常简单（仅超离心）且产率非常高，这是制备许多具有特定性质和功能的缩短的分离的单壁碳纳米管的优点，其可应用于许多领域，包括体内生物应用，如成像、NIR-热疗、光动力学疗法等。
We describe a novel single-walled carbon nanotube (SWNT) cutting method without introducing any structural defects on the tubes; namely, the finding that simple ultracentrifugation at 600 000g for the SWNTs coated with a cross-linked polymer formed by poly(N-isopropylacrylamide) (PNIPAM) or the polyethylene glycol-carrying PNIPAM copolymer provides shortened (<200 nm) SWNTs, which was revealed by dynamic light scattering (DLS) and atomic force microscopy (AFM) measurements. The Raman and absorption measurements of the obtained SWNTs indicated that the graphitic structure and optical properties, such as characteristic absorption and photoluminescence in the near-IR region of the SWNTs, were almost unchanged even after the cutting. The obtained shortened SWNTs were individually solubilized in water and buffer solution due to the remaining cross-linked polymer structures on the SWNTs. The present method is very simple (only ultracentrifugation) and the yield is very high, which are the advantages in the preparation of many shortened isolated SWNTs with specific properties and functions that are applicable in many fields including bioapplications in vivo, such as imaging, NIR-hyperthermic treatment, photodynamic therapy, etc.