Carbon Nanotubes - Research and Applications

ChemOnTubes 2012, Arcachon, France, April 1st - 5th 2012

noreply@blogger.com (Osváth Zoltán) — Wed, 16 Nov 2011 09:37:00 +0000

International meeting on the chemistry of nanotubes and graphene

After three conferences (2006, 2008 and 2010) and an increasing number of participants, the 4th occurrence of ChemOnTubes will be held again in the unique setting of Arcachon Convention Center, in april 2012. In addition to carbon nanotubes, which were the focus of conferences of 2006 and 2008, graphene is now a major subject for carbon chemists and is undertaking a significant scientific development. Since 2010, ChemOnTubes has opened up to the chemistry of graphene, while retaining many presentations around nanotubes. Likewise, the sessions of the ChemOnTubes 2012 conference will also be entirely dedicated to the chemistry of carbon nanotubes and graphene:

Functionalization, Dispersion, Sorting Composites, Porous Materials, Coatings, Energy Storage, Conversion and Harvesting, Nanomedicine, Biomaterials, Functional Materials, Catalysis, Filtration, Membranes, Organic Electronics

Deadline for abstract submission: 15 December 2011

See more details on the conference website: ChemOnTubes 2012

CARBON2011 (24-29 July 2011, Shanghai, China)

noreply@blogger.com (Osváth Zoltán) — Thu, 12 May 2011 12:52:00 +0000

The Annual World Conference on Carbon, which is held in the American, Asian, and European continents alternately since 2000, is a unique chance for the academic and industrial people involved in the science and technology of carbon materials and relative fields to assemble and discuss their current research. East China University of Science and Technology, University of Shanghai for Science and Technology, and Institute of Coal Chemistry, Chinese Academy of Sciences, co-host the Carbon2011 under the guidance the Asian Association of Carbon Groups.

With the rapid development of carbon science and technology, carbon materials play an important role in our daily life. Carbon is old, but it is new. With discoveries of fullerene in 1985, carbon nanotube in 1991 and graphene in 2004, carbon always attracts much attention. “Nice Carbon, Nice Life” is the theme for Carbon2011 and will become a forever theme.

The conference will cover all topics on Carbon Materials and Application. Sessions will be organized around the following topics:

1   Graphene
2   Nanocarbons
3   Carbon for Energy Storage and Conversion
4 Porous carbon and Adsorption
5   Carbon Fibers and Composites
6   Precursor, Carbonization and Graphitization
7   Computation and Modeling
8   Bio-carbon and Safety
9   Novel Experimental Techniques and Characterization
10 Bulk Carbon and Industrial Applications

Conference website

NANOCARBONS 2011

noreply@blogger.com (Osváth Zoltán) — Tue, 05 Apr 2011 08:30:00 +0000

Researchers from the Physical and Life Sciences are invited to participate in the **Nanocarbons 2011** Conference.
This conference is organised by the European Science Foundation (ESF).
The conference will take place on **6 - 11 September 2011** at Hotel Villa del Mare, Acquafredda di Maratea, Italy.

Submission Deadline: **29 May 2011**
**Grants for Young and Early Stage Researchers available.**
Further information can be found below and at: www.esf.org/conferences/11363
**Nanocarbons 2011: Carbon Nanotubes and Related Materials: From Physico-Chemical Properties to Biological and Environmental Effects**

6 - 11 September 2011

**Chaired by:**
**Dr. Sophie Lanone**, Inserm U955 - Équipe 04, FR

**Co-Chairs:**
**Dr. Pascale Launois**, CNRS-Université Paris 11, FR
**Professor Philippe Lambin**, University of Namur, BE
**Professor Stephen Klaine**, Clemson University, US

Programme

Nanomaterials have specific properties mainly governed by quantum physics or surface effects, and significantly different from those of macroscopic objects. Emblematic nanomaterials are carbon nanotubes, which have generated a worldwide, and highly competitive, scientific research activity. The general aim of this conference is, thanks to its pluridisciplinary approach, to give the different actors of carbon nanotubes (CNT) research (physicists, chemists, biologists) the proper level of knowledge required to discuss with the other participants and understand each other correctly. The conference will therefore propose courses accessible to scientists of different fields, as well as more specialized courses in each domain of interest, including the most recent advances on the subject. The program will focus on four general topics: synthesis/characterization of CNT, CNT chemistry, health effects of CNT, and environmental effects of CNT. This conference should allow scientists from the different fields to acquire, increase and share their specific knowledge, and to make their own research understandable to scientists from other disciplines.
[More]

Invited speakers will include

**Mélanie Auffan** - CEREGE Europole Méditerranéen de l'Arbois, FR
**Laszlo P. Biro** - Research Institute for Technical Physics & Materials Science, HU
**Davide Bonifazi** - FUNDP, BE
**Vince Castranova** - National Institute for Occupational Safety and Health (NIOSH), US
**Laurent Cognet** - Université Bordeaux 1, CNRS (UMR 5798), FR
**Alison Elder** - University of Rochester, US
**Chris Ewels** - Institut des Matériaux Jean Rouxel, FR
**Teresa Fernandes** - Edinburgh Napier University, US
**Emmanuel Flahaut** - Université Paul Sabatier, FR
**Dirk Guldi** - Friedrich-Alexander-Universität Erlangen-Nürnberg, DE
**Roland Hischier** - EMPA, CH
**Agnes Kane** - Brown University, US
**Mathieu Kociak** - Univ. Paris Sud, FR
**Dominique Lison** - TOXI, BE
**Craig Poland** - Institute of Occupational Medicine, UK
**Aaron Roberts** - University of North Texas, US
**Michael Strano** - MIT, US
**Antoine Thill** - CEA Saclay, FR

How to Participate

Attendance is possible only after successful application. Full conference programme and application form accessible from www.esf.org/conferences/11363
A certain number of grants are available for students and early stage researchers to cover the conference fee and possibly part of the travel costs.

Closing date for applications: **29 May 2011**

Sponsor a Conference

This conference will be providing the opportunity for leading scientists and young researchers to meet for discussions on the most recent developments in their fields of research. We enable collaboration between international scientists from EU, first world and emerging countries which acts as a catalyst for creating new synergistic global contacts across disciplines.

We invite you to join us in harnessing this great potential, working towards an even more cohesive scientific force in Europe and beyond by contributing to our intense, dynamic and fun events.

If you are interested, please visit our **Sponsor Resource Center** page:
www.esf.org/activities/esf-conferences/sponsor-resource-center.html

EUROMAT 2011

noreply@blogger.com (Osváth Zoltán) — Thu, 10 Feb 2011 22:12:00 +0000

A Symposium "Carbon Nanotubes and Graphene" will be organized at the EUROMAT 2011 conference in Montpellier, 12-15 September 2011.

Extended deadline for abstracts submission : 15/02/2011
-------------------------------------------------------------------------------------------------------------------------------------------------------
The symposium will especially focus on progress and hot topics related to large scale production/processing, applications and industrial issues. This specifically includes :

- Synthesis and selection methods
- Electronic, optical and mechanical properties of carbon nanotubes, graphene and related devices
- Functionnalization, dispersion, processing
- Metrology and standardization
- Composites and materials science
- Other applications and industrial issues

Graphene and the Carbon Revolution

noreply@blogger.com (Osváth Zoltán) — Sun, 05 Dec 2010 13:14:00 +0000

New educative video by Dr. Jonathan Hare about the different forms of carbon. Enjoy!

ElecMol’10

noreply@blogger.com (Osváth Zoltán) — Thu, 07 Oct 2010 15:59:00 +0000

5th International Meeting on Molecular Electronics to be held in Grenoble, France, from 6 to 10 December 2010. It will address eight topics (and respective keywords):

- T1: Single Molecules & Quantum Dots

devices, junctions, switches, nanocrystals, memories

- T2: Organic Electronics and Spintronics

OLED, OFET, single spin, molecular magnet

- T3: Organic Optoelectronics & Photonics

PV, laser, plasmonics

- T4: Graphene, Carbon Nanotubes & Nanowires

Functionnalization, preparation, characterization, integration

- T5: Self-Assembly & Supramolecular Architectures

SAMs, LB, LBL, molecular motors and machines, liquid crystals, block copolymers, supramolecular chemistry, switches, logic gates

- T6: Scanning Probe Microscopies & Near Field Approaches

STM, SNOM, AFM and derivatives, organization on surfaces

- T7: Molecular Theoretical Modeling

Quantum transport, MD, DFT

- T8: Bioinspired Approaches & Biomimetic Devices

DNA, membranes, nano-pores, micelles, catalysis, biomimetic, enzymes, photosynthetic systems, nanobiosensors

For more information, please visit the ElecMol 2010 website.

Scientific papers "in press"

noreply@blogger.com (Osváth Zoltán) — Thu, 19 Aug 2010 10:08:00 +0000

- Dispersion of multi walled carbon nano tubes in a hydrogen bonded liquid crystal

- Tailoring optical and electrical properties of carbon nanotube networks for photovoltaic applications

- Blue-green luminescence by SWCNT/ZnO hybrid nanostructure synthesized in a simple chemical route

- Aptamers based electrochemical biosensor for protein detection using carbon nanotubes platforms

- Nafion and Carbon Nanotube nanocomposites for Mixed Proton and Electron conduction

- An increase in gas sensitivity and recovery of an MWCNT-based gas sensor system in response to an electric field

Inner space

noreply@blogger.com (Osváth Zoltán) — Tue, 27 Jul 2010 12:21:00 +0000

Nanomaterials confined within the inner space of carbon nanotubes (CNTs) exhibit unusual behavior that differs from that of bulk materials; extensive research has been thus carried out on the encapsulation of various molecules in the inner space of CNTs in order to discover new properties of the nanomaterials. The chemically and mechanically stable pseudo-1D confined nanospace of CNTs can serve as an ideal environment for the template assembly of various nanomaterials. Since the confined nanospace of a CNT prevents molecules from reacting, as it impedes their movement, it can potentially be utilized for stable storage of various reactive materials. More

Buckypaper improves fire retardancy of plastic materials

noreply@blogger.com (Osváth Zoltán) — Tue, 27 Jul 2010 12:18:00 +0000

Flame retardant materials have become a major business for the chemical industry and can be found practically everywhere in modern society. Unfortunately, conventional methods for making plastic flame retardant involve a range of often very toxic chemicals. It has already been demonstrated that the flame retardancy of polymeric materials without the use of toxic chemicals could become possible thanks to the synergistic effect of nanoclay and carbon nanotubes. In a step further, researchers have now shown that the use of buckypaper is more efficient as a fire retardant in polymer composites in comparison to directly mixing carbon nanotubes into the composite matrix. More

Using carbon nanotubes in lithium batteries can dramatically improve energy capacity

noreply@blogger.com (Osváth Zoltán) — Tue, 27 Jul 2010 12:11:00 +0000

Batteries might gain a boost in power capacity as a result of a new finding from researchers at MIT. They found that using carbon nanotubes for one of the battery's electrodes produced a significant increase - up to tenfold - in the amount of power it could deliver from a given weight of material, compared to a conventional lithium-ion battery. More

Insights for Carbon Nanotube Technology (Nanocyl CNT Newsletter March 2010)

noreply@blogger.com (Osváth Zoltán) — Mon, 12 Apr 2010 14:36:00 +0000

Key Initiatives Bring Bottom Line Benefits to Customers

Nanocyl's customers have a lot to look forward to in 2010—a bigger supply of high-quality carbon nanotubes, new global technical service, and more support in growing regional markets.

In 2009, we launched several initiatives to make this possible:
• Installed a 5,000 metric tons/year extrusion line for
PLASTICYL thermoplastic concentrates
• Developed high temperature thermoplastic compounds such as PEEK and PEI
• Upscaled the existing reactor to produce 60 metric tons/year of NC 7000 multi-wall CNTs

In 2010, we will have a new 400 metric tons/year reactor coming online in July for producing NC 7000 MWCNTs.
Also, a dedicated team of technical support specialists has been created to help you hasten the launch of your CNT projects. You can reach them at techsupport@nanocyl.com.
Finally, we opened Nanocyl Inc. in the U.S. as well as Nanocyl Chemical Korea.
Let us help you continue to prosper your business in 2010.

How to Successfully Compound CNTs for Conductive Plastic Applications

You can find the complete answers in the technical article, "Influence of Processing Conditions on Electrical Conductivity of PP/CNT Nanocomposites," recently presented at the Society of Plastics Engineers (SPE) 6th European Conference on Additives and Colors.

New Technical Paper Shows the Influence of Moulding Parameters on Polycarbonate NC 7000 Nanocomposites

In the technical paper, "Optimization of Injection Moulding Parameters to Maximize Surface Resistivity on PC/NC 7000 Compounds Requiring Perfect Surface Finishing," you can find out more information about the importance of injection speed and moulding temperature, as well as six practical guidelines for achieving the right surface quality and conductivity.

Nordmann, Rassmann Appointed as Distributor for Germany

We have appointed Nordmann, Rassmann (NRC) to be our commercial partner for NC 7000 MWCNTs and PLASTICYL thermoplastic concentrates marketed in Germany.
Download the press release

Nanocyl to Exhibit at Global Trade Events

Want to learn firsthand about the newest CNT products? Then talk with us at any of these trade events:
• Nanocomposites & Nanotubes Conference,
Brussels (Belgium), March 24-25
• JEC Composites, Paris (France),
April 13-15
• American Coatings Show 2010,
Charlotte NC (USA), April 13-15
• Chinaplas 2010, Shanghai (China),
April 19-22
• Nano Korea, Seoul (South Korea),
Aug. 26-28
• DISKCON USA 2010, Santa Clara (CA),
Sept. 23-24
• K-Show 2010, Dusseldorf (Germany),
Oct. 27-Nov. 3

Send us an email at sales@nanocyl.com with the trade event you’re attending, and we will finalize the best day and time with you.

Join Nanocyl at the Premier Conference in Europe for Applied Carbon Nanotubes

noreply@blogger.com (Osváth Zoltán) — Fri, 12 Mar 2010 10:41:00 +0000

Nanocyl is pleased to invite you to the Nanocomposites/Nanotubes 2010 Conference, on 24th-25th March, at the Radisson Blu Hotel in Brussels.

Take this opportunity to:

Learn about the latest industrial applications, presented by the leading chemical companies
Hear useful case studies about CNT utilization in TPU, PC, POM and other materials
Get practical information and technical support for reaching good surface quality in moulded parts
Gain first-hand knowledge on the newest advances, trends and regulations
Expand your professional network of contacts, resources and CNT experts

Also, be sure to see the presentation on Wednesday the 24th, “Carbon Nanotubes: Review of Their Actual Applications and Trends for the Future”, given by Dr. Michael Claes, Director of Nanocyl’s Technical Support Team.

In his presentation, Dr. Claes will share information about:

New ways to use CNTs as a cost-competitive and innovative solution for emerging applications
Case studies: How conductive masterbatches can be used in grades PC, PEEK, PEI, POM, PA6 and PA12
Performance advantages of CNTs in electronics, packaging, and automotive fuel pump lines
Overview of carbon nanotube technologies for elastomers and composites

For more information about Nanocyl’s participation in the conference, please contact Mr. Ruyssen, Business Development Analyst, at Denis.Ruyssen@nanocyl.com.

Also, register today for the conference. If you register via Nanocyl, you can get a 20% discount. Simply contact Mr. Ruyssen at Denis.Ruyssen@nanocyl.com for your discount form.

Or, you can go to www.nanosconference.com, and click on Register Now.

Evidence for electro-chemical interactions between multi-walled carbon nanotubes and human macrophages

noreply@blogger.com (Osváth Zoltán) — Fri, 21 Aug 2009 12:46:00 +0000

Carbon multi-walled nanotubes (MWCNTs) may have several dangerous effects on different cell systems, but the mechanisms responsible for their cytotoxicity are not well known yet. At present, very little is known about the electrical interactions between nanomaterials and cells. We aimed to verify whether MWCNT electrical properties could affect the so called “charge-sensitive” cell parameters, interacting with cellular electrical activity. Human macrophages were challenged with two fully characterised MWCNT samples, one tested as-prepared (MWCNT), the other one purified (by annealing at 2400 °C) and better electro-conductive (a-MWCNT). Our findings show that a-MWCNTs are less cytotoxic but possess a higher inflammatory potential, as compared to MWCNTs.

Moreover, only annealed and better conductive MWCNTs affect significantly the mitochondrial membrane polarity, the intracellular pH and the reorganisation of cytoskeleton actin filaments, cell functions strictly dependent on electro-chemical mechanisms. Based on our results, there is evidence for electro-chemical interactions taking place between cell membranes and electro-conductive MWCNTs. Such a specific behaviour could have wide-range applications in the biomedical field, not only concerning those cellular systems (neuronal and bone cells) sensitive to electrical stimuli, but also other cell systems.
(Silvana Fiorito, et al., Carbon Volume 47, Issue 12, 2009, Pages 2789-2804, doi:10.1016/j.carbon.2009.06.023)

A novel nanostructured poly(lactic-co-glycolic-acid)–multi-walled carbon nanotube composite for blood-contacting applications: Thrombogenicity studies

noreply@blogger.com (Osváth Zoltán) — Fri, 21 Aug 2009 12:40:00 +0000

Composite films of poly(lactic-co-glycolic-acid) with multi-walled carbon nanotubes (PLGA–MWCNT) having two different nanotube orientations, namely random and vertically aligned, have been fabricated and characterized. The effect of these nanostructured surfaces on platelet adhesion is evaluated. In particular, the thrombogenicity of the nanostructured composite films is compared with that of pristine graphite (a low thrombogenic material) and PLGA film, in order to determine the influence of surface chemistry and topography on platelet adhesion. The results in this study show that the PLGA–MWCNT composite with vertically aligned nanotubes exhibits very low levels of fibrinogen adsorption and platelet adhesion, which can be attributed to both chemical and topographical effects. Platelet adhesion shows a good correlation with the presence of COOH groups and appears to be sensitive to the topographic features of the composite films. The results in this study suggest that in addition to chemistry, nanotopographical surface modifications could be an effective strategy in the development of low thrombogenic and hemocompatible materials.
(Li Buay Koh, Isabel Rodriguez and Subbu S. Venkatraman, Acta Biomaterialia
Article in Press, doi:10.1016/j.actbio.2009.06.003)

Carbon nanotubes-graft-polyglycerol: Biocompatible hybrid materials for nanomedicine

noreply@blogger.com (Osváth Zoltán) — Fri, 21 Aug 2009 12:31:00 +0000

New biocompatible and water soluble hybrid materials containing multi-wall carbon nanotubes (MWCNTs) as core and hyperbranched polyglycerol (PG) as shell were synthesized successfully. In this work, pristine MWCNTs were opened and functionalized through treatment with acid and polyglycerol was covalently grafted onto their surface by the “grafting from” approach based on in-situ ring-opening polymerization of glycidol. Some short-term In vitro cytotoxicity and hemocompatibility tests were conducted on HT1080 cell line (human Fibrosarcoma), because this epithelial cell line can be one of the first route of entry of the exogenous materials to the vascular system and therefore subsequent interactions with the whole body, in order to investigate their potential application in nanomedicine and to understand the limitation and capability of these material as nanoexcipients in biological systems.

(Mohsen Adeli, Narjes Mirab, Mohammad Shafiee Alavidjeh, Zahra Sobhani and Fatemeh Atyabi, Polymer Volume 50, Issue 15, 17 July 2009, Pages 3528-3536, doi:10.1016/j.polymer.2009.05.052)

Gas sensors for ammonia detection based on polyaniline-coated multi-wall carbon nanotubes

noreply@blogger.com (Osváth Zoltán) — Thu, 30 Jul 2009 08:26:00 +0000

Polyaniline-coated multi-wall carbon nanotubes (PANI-coated MWNTs) were prepared by in situ polymerization method. Field emission scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and thermogravimetric analysis were used to characterize the as-prepared PANI-coated MWNTs. Obtained results indicated that PANI was uniformly coated on MWNTs, and the thickness of the coatings can be controlled by changing the weight ratios of aniline monomer and MWNTs in the polymerization process. Sensors were fabricated by spin-coating onto pre-patterned electrodes, and ammonia gas sensing properties of the as-prepared PANI-coated MWNTs were studied. The results showed a good response and reproducibility towards ammonia at room temperature. In addition, PANI-coated MWNTs exhibited a linear response to ammonia in the range of 0.2–15 ppm. The effects of the thickness of PANI coatings on the gas sensing properties were also investigated in detail. The results suggest a potential application of PANI-coated MWNTs in gas sensor for detecting ammonia.

(Lifang He, Yong Jia, Fanli Meng, Minqiang Li, and Jinhuai Liu, Materials Science and Engineering: B 163, Issue 2, 15 July 2009, Pages 76-81, doi:10.1016/j.mseb.2009.05.009)

Toxicity and imaging of multi-walled carbon nanotubes in human macrophage cells

noreply@blogger.com (Osváth Zoltán) — Thu, 30 Jul 2009 08:19:00 +0000

Multi-walled carbon nanotubes (MWNTs) have been proposed for use in many applications and concerns about their potential effect on human health have led to the interest in understanding the interactions between MWNTs and human cells. One important technique is the visualisation of the intracellular distribution of MWNTs. We exposed human macrophage cells to unpurified MWNTs and found that a decrease in cell viability was correlated with uptake of MWNTs due to mainly necrosis. Cells treated with purified MWNTs and the main contaminant Fe₂O₃ itself yielded toxicity only from the nanotubes and not from the Fe₂O₃. We used 3-D dark-field scanning transmission electron microscopy (DF-STEM) tomography of freeze-dried whole cells as well as confocal and scanning electron microscopy (SEM) to image the cellular uptake and distribution of unpurified MWNTs. We observed that unpurified MWNTs entered the cell both actively and passively frequently inserting through the plasma membrane into the cytoplasm and the nucleus. These suggest that MWNTs may cause incomplete phagocytosis or mechanically pierce through the plasma membrane and result in oxidative stress and cell death.

(Crystal Cheng, Karin H. Müller, Krzysztof K.K. Koziol, Jeremy N. Skepper, Paul A. Midgley, Mark E. Welland, and Alexandra E. Porter, Biomaterials 30, Issue 25, September 2009, Pages 4152-4160, doi:10.1016/j.biomaterials.2009.04.019)

Multifunctionality of single-walled carbon nanotube–polytetrafluoroethylene nanocomposites

noreply@blogger.com (Osváth Zoltán) — Thu, 30 Jul 2009 08:14:00 +0000

Multifunctional nanocomposites are increasingly needed for applications requiring prescribed sets of physical and chemical properties. Polytetrafluoroethylene (PTFE) is a popular solid lubricant due to its low friction coefficient, high chemical inertness, high thermal range and biocompatibility, but its use is limited by high rates of wear. Low loadings of nanoparticle fillers have reduced PTFE wear by 3–4 orders of magnitude, but these materials lack the mechanical, electrical or thermal properties needed for high performance applications.

In this study, single-walled carbon nanotubes (SWCNT) are investigated as a route to improve wear resistance, toughness and electrical conductivity of PTFE without sacrificing low friction, high temperature capability or chemical inertness. Tribological, tensile and surface electrical measurements were made for 0, 2, 5, 10 and 15 wt.% SWCNT filled PTFE nanocomposites. A dramatic reduction in electrical resistance reflected networking (percolation) of the nanotubes at 2 wt.%. All of the nanocomposites had significantly improved electrical, mechanical and wear performance. Above 2 wt.%, electrical conductivity was reduced by more than six orders of magnitude. At 2 wt.%, ultimate engineering stress was improved by approximately 50%, true stress increased by 200%, engineering strain increased by two orders of magnitude (10,000%). At 5 wt.%, wear resistance improved by more than 20 times and friction coefficient increased by 50%.
(J.R. Vail, D.L. Burris, and W.G. Sawyer, Wear 267, Issues 1-4, 15 June 2009, Pages 619-624, doi:10.1016/j.wear.2008.12.117)

Effects of carbon nanotubes on primary neurons and glial cells

noreply@blogger.com (Osváth Zoltán) — Tue, 23 Jun 2009 09:04:00 +0000

Carbon nanotubes (CNTs) are among the most promising novel nanomaterials and their unique chemical and physical properties suggest an enormous potential for many areas of research and applications. As a consequence, the production of CNT-based material and thus the occupational and public exposure to CNTs will increase steadily. Although there is evidence that nanoparticles (NPs) can enter the nervous system via the blood stream, olfactory nerves or sensory nerves in the skin, there is still only little knowledge about possible toxic effects of CNTs on cells of the nervous system.

The goal of the present study was to analyse the influences of single-walled CNTs (SWCNTs) with different degrees of agglomeration on primary cultures derived from chicken embryonic spinal cord (SPC) or dorsal root ganglia (DRG). As measured by the Hoechst assay treatment of mixed neuro-glial cultures with up to 30 μg/mL SWCNTs significantly decreased the overall DNA content. This effect was more pronounced if cells were exposed to highly agglomerated SWCNTs as compared to better dispersed SWCNT-bundles. Using a cell-based ELISA we found that SWCNTs reduce the amount of glial cells in both peripheral nervous system (PNS) and central nervous system (CNS) derived cultures. Neurons were only affected in DRG derived cultures, where SWCNT treatment resulted in a decreased number of sensory neurons, as measured by ELISA. Additionally, whole-cell patch recordings revealed a diminished inward conductivity and a more positive resting membrane potential of SWCNT treated DRG derived neurons compared to control samples.

The SWCNT suspensions used in this study induced acute toxic effects in primary cultures from both, the central and peripheral nervous system of chicken embryos. The level of toxicity is at least partially dependent on the agglomeration state of the tubes. Thus if SWCNTs can enter the nervous system at sufficiently high concentrations, it is likely that adverse effects on glial cells and neurons might occur.

(Larisa Belyanskaya, Stefan Weigel, Cordula Hirsch, Ursina Tobler, Harald F. Krug, and Peter Wick, NeuroToxicology, Article in Press, 2009, doi:10.1016/j.neuro.2009.05.005)

Showa Denko develops new CNT grade, cooperates with Hyperion

noreply@blogger.com (Osváth Zoltán) — Tue, 23 Jun 2009 08:59:00 +0000

Japan's Showa Denko KK (SDK) has developed VGCF™-X, a new grade of SDK carbon nanotube (CNT) with an optimized design for resin composite applications. The company says it will begin construction of a 400 t/year plant to manufacture the new product at its Oita complex in March 2009. The plant, due to start up in 2010, will benefit from a cost-competitive position since it can fully utilize the existing utilities at the site.

According to SDK, VGCF-X, which has been developed using the company's catalyst and synthesis technologies, has very high electrical conductivity and dispersibility. Average nanotube diameter is 15–20 nm and length 3 μm, significantly smaller in both dimensions than the company's existing VGCF grades. The new product can impart stable conductivity to resins at low loading levels and is therefore expected to find applications in static-free plastic cases for the carriage of semiconductor/hard disk media parts. Because of increased production of semiconductors with fine structures and hard disk media with higher densities, these plastic cases are required to have higher antistatic levels to prevent contamination to parts and to ensure cleanliness of the air in a clean room.

SDK began developing VGCF products in 1982 under the guidance of Professor Morinobu Endo of Shinshu University, one of the pioneers of CNT synthesis. The company established a high-volume production technology in 1988 and started up a 20 t/year commercial plant in 1996. Capacity was expanded to 100 t/year in 2007. In September 2008, SDK and Endo jointly developed an ultra-high-performance composite rubber for oil exploration/drilling applications using VGCF-S, a finer grade developed for composites. SDK has been expanding its fine carbon operation, centring on VGCF, as one of its growth businesses. The company plans to achieve sales of ¥40 billion from this business in 2015 by developing new applications as well as battery and composite applications.

In addition, SDK has concluded a patent cross-licence and supply agreement with Hyperion Catalysis International, Inc (Cambridge, MA, USA), which owns many key patents pertaining to materials and applications in the area of CNTs, including for resin composites. In exchange for certain payments, royalties and other considerations, SDK will be able to sell CNT-based products for use within a defined field in plastics under Hyperion's extensive patent portfolio. The supply agreement provides that SDK will purchase Hyperion's FIBRIL™ conductive, multi-walled CNT-based products for resale alongside its own product line. According to SDK and Hyperion, these licence and supply agreements will help both firms to maintain and grow their leading positions in the manufacture of CNT-based products for the promising composite market. The two companies have also identified other areas of mutual interest and have initiated discussions regarding possible joint R&D projects.

Hyperion has been manufacturing and selling its FIBRIL CNTs since 1983. Pre-mixed in a range of matrices, they are used in a growing number of automotive, electronics and other applications.

(Additives for Polymers, Volume 2009, Issue 3, March 2009, Pages 3-4 )

Contact: Showa Denko KK, 13-9, Shiba Daimon 1-Chome, Minato-ku, Tokyo 105-8518, Japan. Tel: +81 3 5470 3235, Web: www.sdk.co.jp

Or contact: Hyperion Catalysis International, Inc, 38 Smith Place, Cambridge, MA 02138, USA. Tel: +1 617 354 9678, Web: www.hyperioncatalysis.com

Electrophoretic deposition of carbon nanotube–ceramic nanocomposites

noreply@blogger.com (Osváth Zoltán) — Tue, 23 Jun 2009 08:51:00 +0000

The purpose of this paper is to present an up-to-date comprehensive overview of current research progress in the development of carbon nanotube (CNT)–ceramic nanocomposites by electrophoretic deposition (EPD). Micron-sized and nanoscale ceramic particles have been combined with CNTs, both multiwalled and single-walled, using EPD for a variety of functional, structural and biomedical applications.

Systems reviewed include SiO₂/CNT, TiO₂/CNT, MnO₂/CNT, Fe₃O₄/CNT, hydroxyapatite (HA)/CNT and bioactive glass/CNT. EPD has been shown to be a very convenient method to manipulate and arrange CNTs from well dispersed suspensions onto conductive substrates. CNT–ceramic composite layers of thickness in the range <1–50 μm have been produced. Sequential EPD of layered nanocomposites as well as electrophoretic co-deposition from diphasic suspensions have been investigated. A critical step for the success of EPD is the prior functionalization of CNTs, usually by their treatment in acid solutions, in order to create functional groups on CNT surfaces so that they can be dispersed uniformly in solvents, for example water or organic media.

The preparation and characterisation of stable CNT and CNT/ceramic particle suspensions as well as relevant EPD mechanisms are discussed. Key processing stages, including functionalization of CNTs, tailoring zeta potential of CNTs and ceramic particles in suspension as well as specific EPD parameters, such as deposition voltage and time, are discussed in terms of their influence on the quality of the developed CNT/ceramic nanocomposites. The analysis of the literature confirms that EPD is the technique of choice for the development of complex CNT–ceramic nanocomposite layers and coatings of high structural homogeneity and reproducible properties. Potential and realised applications of the resulting CNT–ceramic composite coatings are highlighted, including fuel cell and supercapacitor electrodes, field emission devices, bioelectrodes, photocatalytic films, sensors as well as a wide range of functional, structural and bioactive coatings. (A.R. Boccaccini, J. Cho, T. Subhani, C. Kaya and F. Kaya, Journal of the European Ceramic Society, Article in Press, 2009, doi:10.1016/j.jeurceramsoc.2009.03.016)

Electrochemical properties of interface formed by interlaced layers of DNA- and lysozyme-coated single-walled carbon nanotubes

noreply@blogger.com (Osváth Zoltán) — Tue, 23 Jun 2009 08:48:00 +0000

Multifunctional coatings were produced by the layer by layer assembly of single-walled carbon nanotubes (SWNT) dispersed in DNA and lysozyme (LSZ) on an insulating glass substrate. The electrochemical properties of these mechanically robust biocoatings were characterized for the first time using scanning electrochemical microscopy (SECM) and impedance spectroscopy (IS). SECM surface analysis demonstrated an increase in tip current with a corresponding increase in the number of oppositely polarized interlaced layers, indicating that subsequent layers were not electrically insulated from each other and a direct correlation exists between SECM feedback response and the number of layers.

The rate of charge transport was also dependent on the chemical composition/polarity of the outermost surface layer. Coatings terminating in SWNT-DNA resulted in more positive feedback than those terminating in SWNT-LSZ. IS analysis demonstrated that the SWNT-DNA had a low charge transfer resistance in comparison with SWNT-LSZ, which is consistent with the results obtained by SECM. These results enable enhanced fundamental understanding and prediction of the electrical properties of SWNT-biopolymer layers with controlled interlaced polarities and orientation. Furthermore, these finding highlight the potential for SWNT-biopolymers in electronic and sensing applications.
(Valber A. Pedrosa, Tony Gnanaprakasa, Shankar Balasubramanian, Eric V. Olsen, Virginia A. Davis, and Aleksandr L. Simonian, Electrochemistry Communications, Article in Press, 2009, doi:10.1016/j.elecom.2009.05.016)

Preparation and characterization of highly conductive transparent films with single-walled carbon nanotubes for flexible display applications

noreply@blogger.com (Osváth Zoltán) — Wed, 10 Jun 2009 11:46:00 +0000

Dense, aligned single-walled carbon nanotubes (SWCNTs) were obtained by nitric acid treatment and the subsequent removal of metal impurities by HCl. The highly purified SWCNTs were dispersed with sodium dodecyl sulfate in order to obtain a stabilized suspension for spray coating on flexible polyethylene terephthalate (PET) substrate. The low sheet resistance of the resulting thin conductive film on the PET substrate was due to the interconnecting networks of highly purified SWCNT bundles. These bundles formed strong crisscross networks of nanotubes clustered together with well defined channels, thus improving the electrical and optical properties of the film. Its sheet resistance varied from 956 to 472 Ω/square with 85% optical transmittance at a wavelength of 550 nm. The films may be potential candidates for flexible display applications.
(Santhosh Paul and Dong-Won Kim, Carbon, Article in Press, 2009, doi:10.1016/j.carbon.2009.04.045)

Molecular imaging with single-walled carbon nanotubes

noreply@blogger.com (Osváth Zoltán) — Wed, 10 Jun 2009 11:41:00 +0000

Nanoparticle-based molecular imaging has emerged as an interdisciplinary field which involves physics, chemistry, engineering, biology, and medicine. Single-walled carbon nanotubes (SWCNTs) have unique properties which make them suitable for applications in a variety of imaging modalities, such as magnetic resonance, near-infrared fluorescence, Raman spectroscopy, photoacoustic tomography, and radionuclide-based imaging. In this review, we will summarize the current state-of-the-art of SWCNTs in molecular imaging applications. Multifunctionality is the key advantage of nanoparticles over traditional approaches. Targeting ligands, imaging labels, therapeutic drugs, and many other agents can all be integrated into the nanoparticle to allow for targeted molecular imaging and molecular therapy by encompassing many biological and biophysical barriers. A multifunctional, SWCNT-based nanoplatform holds great potential for clinical applications in the future.

(Hao Hong, Ting Gao, and Weibo Cai, Nano Today 4, 2009, 252,
doi:10.1016/j.nantod.2009.04.002)

Carbon nanotube-based transducers for immunoassays

noreply@blogger.com (Osváth Zoltán) — Wed, 10 Jun 2009 11:30:00 +0000

The attachment of mouse immunoglobulin G (IgG) and anti-mouse IgG antibodies onto carbon nanotubes (CNTs), using either non-covalent or covalent means was investigated. The resultant CNTs were characterised using a variety of techniques including enzyme-linked and fluorescence-linked immunoassays, UV–visible-NIR and Raman spectroscopy, transmission electron microscopy and cyclic voltammetry.
TEM images of the adsorbed antibody on the CNTs show that the covalent modification approach was successful, whereas the non-covalent approach resulted in no electrochemically detectable labelled antibody. Direct electrical communication between CNTs covalently linked to peroxidase-labelled antibodies was observed during cyclic voltammetry, which suggests applications in developing carbon-nanotube-based immunosensors.
(Carol Lynam, Niamh Gilmartin, Andrew I. Minett, Richard O’Kennedy, and Gordon Wallace, Carbon, Article in Press, 2009, doi:10.1016/j.carbon.2009.04.017)