单壁碳纳米管的提纯方法

采用温控电弧炉，在600℃下，使用Fe／Ni/Mg催化剂大量制备了单壁碳纳米管。用两步纯化方法对单壁纳米管进行提纯：首先，原始的单壁碳纳米管在500℃，空气中加热30min；接着用37％的盐酸浸泡加热后的样品72h，水洗过滤后烘干,通过SEM、TGA、HRTEM和激光拉曼表征，纯化后单壁碳纳米管的纯度可高达95％，其直径范围为：1.24-1.38nm。     

单壁碳纳米管束的排布

流体排布法是实现碳纳米管定向排列的一种简单的方法。采用流体排布法在具有浸润性图案化的基底上成功地对单壁碳纳米管(SWNTs)束进行了水平方向上的排布。将SWNTs悬浮液滴入光刻胶制成的微通道中,在流体剪切力作用下,弯曲的SWNTs在一定程度上会被拉伸并且平行地排列在纳米级宽度的微通道中。将排列好的SWNTs阵列转移到一些不同间距的金电极对上面,制作成碳纳米管场效应晶体管(CNTFET)。CNTFET的电性能测试结果表明,制备的SWNTs束可以制造出不同电极间距同时具有良好电性能的CNTFET。     

用气相流动催化热解法合成单壁碳纳米管

以正硅酸乙酯(TEOS)为前驱体，二茂铁为催化剂前驱体，利用气相流动催化热解法在850～1160℃连续合成了单壁碳纳米管(SWNTs)．在此过程中，以由TEOS分解得到的二氧化硅颗粒和二茂铁分解得到的铁颗粒在气流中直接形成的复合粒于作为催化剂，二氧化硅作为铁颗粒的载体．电于显微镜和激光拉曼光谱的观测和分析表明，在所得到的产物中SWNTs的含量约为10％，其直径为1～2nm。     

Mitochondria-targeting single-walled carbon nanotubes for cancer photothermal therapy

Nanomaterials have recently attracted much attention as efficient transducers for cancer photothermal therapy, based on their intrinsic absorption properties in the near-infrared region. This study explores a novel therapy model with mitochondria-targeting single-walled carbon nanotubes (SWNTs), which act efficiently to convert 980-nm laser energy into heat and selectively destroy the target mitochondria, thereby inducing mitochondrial depolarization, cytochrome c release, and caspase 3 activation. The laser+SWNTs process affords remarkable efficacy in suppressing tumor growth in a breast cancer model, and results in complete tumor regression in some cases. Laser+SWNTs could prove to be a promising selective local treatment modality, while minimizing adverse side effects.     

Mitochondria-targeting photoacoustic therapy using single-walled carbon nanotubes

In vitro photoacoustic therapy using modified single-walled carbon nanotubes (SWNTs) as "bomb" agents is a newly reported approach for cancer. Herein, a mitochondria-targeting photoacoustic modality using unmodified SWNTs and its in vitro and in vivo antitumor effect are reported. Unmodified SWNTs can be taken up into cancer cells due to a higher mitochondrial transmembrane potential in cancerous cells than normal cells. Under the irradiation of a 1064 nm pulse laser, 79.4% of cancer cells with intracellular SWNTs die within 20 s, while 82.3% of normal cells without SWNTs remain alive. This modality kills cancer cells mainly by triggering cell apoptosis that initiates from mitochondrial damage, through the depolarization of mitochondria and the subsequent release of cytochrome c after photoacoustic therapy. It is very effective in suppressing tumor growth by selectively destroying tumor tissue without causing epidermis injury. Taken together, these discoveries provide a new method using mitochondria-localized SWNTs as photoacoustic transducers for cancer treatment.     

Functionalized single-walled carbon nanotubes for the improved solubilization and delivery of curcumin

The surface modification of single-walled carbon nanotubes (SWCNTs) can enhance their solubility and stability in water and biological systems. The present study demonstrated the application of the functionalized SWCNTs (f-SWCNTs) as drug-delivery vehicles. In this study, f-SWCNTs were functionalized with one of four different chemical groups for the delivery of curcumin to splenic lymphocytes. Since free curcumin can modulate the proliferation of splenic lymphocytes, we compared the abilities of different f-SWCNTs for the delivery of water-insoluble curcumin to inhibit cell proliferation, which were stimulated with concanavalin A (Con A) and lipopolysaccharide (LPS). The results showed that curcumin can be loaded onto the f-SWCNTs surface through π?π stacking with a loading capacity of 235–327 mg/g (curcumin/f-SWCNTs). The f-SWCNTs-curcumin complexes display considerable cell proliferation inhibition efficacy when compared with free curcumin diluted in dimethyl sulfoxide (DMSO). Furthermore, curcumin loaded onto SWCNTs functionalized with poly(ethylene glycol) (SW-PEG) showed good dispersion and stability in water, confirming the excellent biocompatibility of SW-PEG as a drug carrier.     

用单壁纳米碳管制备葡萄糖生物传感器的研究

以单壁纳米碳管为代表材料,对利用纳米碳管制备葡萄糖生物传感器中纳米碳管的作用和纳米碳管修饰电极的方法、酶的固定化方法及电极种类等因素对传感器性能的影响进行了研究.研究结果表明,纳米碳管的加入能有效地改善传感器的电化学性能,利用二茂铁和单壁纳米碳管共同修饰电极所制得的传感器的性能要好于仅用单壁纳米碳管修饰电极制得的传感器.在酶的固定化方法中,戊二醛交联法要略好于明胶包埋法;而利用铂电极制备出的生物传感器对葡萄糖的响应电流要明显高于利用金电极和玻碳电极制备出的生物传感器.这些结论对于开发纳米碳管在生物传感领域及生命科学相关领域的应用有参考价值.     

Covalent and noncovalent functionalisation and solubilisation of nanodiamond

Covalent functionalisation of nanodiamond has been carried out by employing several methods. One of them involves the reaction of acid-treated nanodiamond with thionyl chloride followed by reaction with a long-chain aliphatic amine to produce the amide derivative. The second method involves reaction of acid-treated nanodiamond with an organosilicon or organotin reagent such as hexadecyltrimethoxysilane, dibutyldimethoxytin, and perfluoro-octyltriethoxysilane. The products of covalent functionalisation produce excellent dispersions in CCl₄ and toluene. SiO₂–and SnO₂–covered nanodiamond are obtained by heating the nanodiamond coated with the organosilane and the organotin reagents, respectively. By interaction of nanodiamond with surfactants such as sodium bis(2-ethylhexyl) sulphosuccinate (AOT), Triton X-100 (TX-100), polyvinyl alcohol (PVA), cetyltrimethylammonium bromide (CTAB), and tert-octylphenoxy poly(oxyethylene)ethanol (IGEPAL) gives good dispersions in water, the best dispersion with the lowest surfactant concentration being obtained with IGEPAL.     

Odako growth of dense arrays of single-walled carbon nanotubes attached to carbon surfaces

A novel process is demonstrated whereby dense arrays of single-walled carbon nanotubes (SWNT) are grown directly at the interface of a carbon material or carbon fiber. This growth process combines the concepts of SWNT tip growth and alumina-supported SWNT base growth to yield what we refer to as “odako” growth. In odako growth, an alumina flake detaches from the carbon surface and supports catalytic growth of dense SWNT arrays at the tip, leaving a direct interface between the carbon surface and the dense SWNT arrays. In addition to being a new and novel form of SWNT array growth, this technique provides a route toward future development of many important applications for dense aligned SWNT arrays. Electronic Supplementary Material  Supplementary material is available for this article at and is accessible for authorized users. This article is published with open access at Springerlink.com     

Synthesis of individual ultra-long carbon nanotubes and transfer to other substrates

In this article, we report the synthesis of ultra-long carbon nanotubes (CNTs) by thermal chemical vapour deposition method. Ultra-long, individual and aligned CNTs were directly grown on a flat silicon substrate. The orientation of the nanotubes was found parallel to the gas flow direction. The ultra-long CNTs were grown with different transition metallic salts, such as nickel chloride, iron (III) chloride, cobalt acetate and ruthenium acetate, as the catalysts. The influence of the growth conditions, such as growth temperature, reactive gas flow on the length and alignment of the CNTs was studied in detail. By using different catalysts, ultra-long single-walled carbon nanotubes (SWCNTs) or multi-walled carbon nanotubes (MWCNTs) were successfully grown. These ultra-long CNTs were transferred to other substrates by two methods. (1) The first method is to use polydimethylsiloxane as a stamp. (2) The second method is to use KOH as an etching agent. The diameter and length of the CNTs were characterised by transmission electron microscope, scanning electron microscope, atomic force microscope and Raman spectroscopy. The results indicate that the length of the CNTs can reach up to 4?mm. The diameter of the SWCNTs is in the range of 0.7–2.1?nm and the diameter of the MWCNTs is approximately 150?nm.     

Carbene-functionalized single-walled carbon nanotubes and their electrical properties

Pure metallic single-walled carbon nanotubes (m-SWCNTs) are very desirable for many electrode and interconnecting applications. However, the lack of reliable processing techniques to sort m-SWCNTs from the as-synthesized SWCNT samples is an obstacle to these applications. The effects of carbene-based covalent functionalization on the electrical properties of an isolated m-SWCNT, a semiconducting (s)-SWCNT, and a mixture network of both m- and s-SWCNTs are reported. For the first time, a semiconducting-to-metallic SWCNT transition upon dichlorocarbene functionalization is observed. Interestingly, the transition is reversible upon thermal annealing under ambient conditions. The electrical properties of m-SWCNTs remain largely unaffected whereas the on-state conductivity of s-SWCNTs is greatly reduced by this process, in agreement with the relevant theoretical predictions. These findings could pave the way for fabricating large-scale SWCNT-based interconnects and electrodes in full-carbon integrated circuits.     

Oligodeoxyribonucleotide association with single-walled carbon nanotubes studied by SPM

Studies have been performed on both as-received and chemically oxidized single-walled carbon nanotubes (SWCNTs) grown by two different growth methods to better understand the preferential association of the oligodeoxyribonucleotide T30 (ODN) with SWCNTs. Samples of T30 ODN:SWCNT were examined under ambient conditions using non-contact scanning probe microscope (SPM) techniques. The resulting images show different morphologies ranging from tangled networks of SWCNTs to individual, well-dispersed isolated SWCNTs as the sonication time is increased. SPM images of well-dispersed, as-received SWCNTs reveal isolated features that are 1.4 to 2.8 nm higher than the bare SWCNT itself. X-ray photoemission spectroscopy (XPS) confirmed these features to be T30 ODN in nature. Chemically oxidizing the SWCNTs before sonication is found to be an effective way to increase the number of T30 ODN features.