Biological Interactions of Functionalized Single-Wall Carbon Nanotubes in Human Epidermal Keratinocytes

Carbon nanotube–based nanovectors, especially functionalized nanotubes, have shown potential for therapeutic drug delivery. 6-Aminohexanoic acid–derivatized single-wall carbon nanotubes (AHA-SWNTs) are soluble in aqueous stock solutions over a wide range of physiologically relevant conditions; however, their interactions with cells and their biological compatibility has not been explored. Human epidermal keratinocytes (HEKs) were dosed with AHA-SWNTs ranging in concentration from 0.00000005 to 0.05 mg/ml. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) cell viability decreased significantly ( p < .05) from 0.00005 to 0.05 mg/ml after 24 h. The proinflammatory mediators of inflammation cytokines interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)- α, IL-10, and IL-1 β were also assessed. Cytokine analysis did not show a significant increase in IL-6 and IL-8 in the medium containing 0.000005 mg/ml of AHA-SWNTs from 1 to 48 h. IL-6 increased in cells treated with 0.05 mg/ml of AHA-SWNTs from 1 to 48 h, whereas IL-8 showed a significant increase at 24 and 48 h. No significant difference ( p < .05) was noted with TNF- α, IL-10, and IL-1 β expression at any time point. Transmission electron microscopy of HEKs treated with 0.05 mg/ml AHA-SWNTs for 24 h depicted AHA-SWNTs localized within intracytoplasmic vacuoles in HEKs. Treatment with the surfactant 1% Pluronic F127 caused dispersion of the AHA-SWNT aggregates in the culture medium and less toxicity. These data showed that the lower concentration of 0.000005 mg/ml of AHA-SWNTs maintains cell viability and induces a mild cytotoxicity, but 0.05 mg/ml of AHA-SWNTs demonstrated an irritation response by the increase in IL-8.

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Scanning Tunneling Microscopy and Spectroscopy Studies of Single Wall Carbon Nanotubes

Journal of Materials Research ◽

10.1557/jmr.1998.0331 ◽

1998 ◽

Vol 13 (9) ◽

pp. 2380-2388 ◽

Cited By ~ 36

Author(s):

Teri Wang Odom ◽

Jin-Lin Huang ◽

Philip Kim ◽

Min Ouyang ◽

Charles M. Lieber

Keyword(s):

Carbon Nanotubes ◽

Scanning Tunneling Microscopy ◽

Single Wall Carbon Nanotubes ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Metallic Behavior ◽

Single Wall Carbon ◽

Wide Range ◽

Theoretical Predictions ◽

Spectroscopy Studies

Scanning tunneling microscopy and spectroscopy have been used to characterize the atomic structure and tunneling density of states of individual single wall carbon nanotubes (SWNT's) and ropes containing many SWNT's. Analysis of atomically resolved SWNT images shows that the nanotubes consist of a wide range of diameters and helicities with no one structure clearly dominant. Tunneling spectroscopy measurements made simultaneously on atomically resolved SWNT's exhibit semiconducting and metallic behavior that depend predictably on helicity and diameter. In addition the band gaps of the semiconducting tubes were also found to depend inversely on diameter. These results are compared to theoretical predictions, and the implications of these studies as well as important future directions are discussed.

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Alignment and Deposition of Single Wall Carbon Nanotubes under the Influence of an Electric Field

MRS Proceedings ◽

10.1557/proc-761-nn5.5/j8.5 ◽

2002 ◽

Vol 761 ◽

Author(s):

Paul Jaynes ◽

Thomas Tiano ◽

Margaret Roylance ◽

Charles Carey ◽

Kenneth McElrath

Keyword(s):

Carbon Nanotubes ◽

Electric Field ◽

Electronic Devices ◽

Physical And Mechanical Properties ◽

Single Wall Carbon Nanotubes ◽

Enabling Technology ◽

Single Wall Carbon ◽

Nanoelectronic Devices ◽

Wide Range ◽

Field Lines

ABSTRACTSingle wall carbon nanotubes have aroused a great deal of interest because of their unique combination of electrical, physical and mechanical properties. However, the widespread use of SWNTs in composites and electronic devices is limited because of the difficulty of dispersing and processing these materials. This paper describes a method for depositing and aligning SWNTs from a dispersed solution onto a substrate under the influence of an electric field. Results indicate that SWNTs can be aligned in bulk in the direction of electric field lines, and that individual SWNT ropes may be deposited between two electrodes. The extent and type of deposition depends upon the electrode geometry and processing time. Electrical alignment of SWNTs is an enabling technology allowing manipulation of nanomaterials using standard processing. It could eventually lead to a wide range of products, such as nanocomposites with aligned fillers and nanoelectronic devices.

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Dispersion of single-wall carbon nanotubes with supramolecular Congo red – properties of the complexes and mechanism of the interaction

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.8.68 ◽

2017 ◽

Vol 8 ◽

pp. 636-648 ◽

Cited By ~ 6

Author(s):

Anna Jagusiak ◽

Barbara Piekarska ◽

Tomasz Pańczyk ◽

Małgorzata Jemioła-Rzemińska ◽

Elżbieta Bielańska ◽

...

Keyword(s):

Carbon Nanotubes ◽

Targeted Delivery ◽

Congo Red ◽

Binding Capacity ◽

Aqueous Media ◽

Strong Interactions ◽

Single Wall Carbon Nanotubes ◽

Scanning Calorimetry ◽

Single Wall Carbon ◽

Wide Range

A method of dispersion of single-wall carbon nanotubes (SWNTs) in aqueous media using Congo red (CR) is proposed. Nanotubes covered with CR constitute the high capacity system that provides the possibility of binding and targeted delivery of different drugs, which can intercalate into the supramolecular, ribbon-like CR structure. The study revealed the presence of strong interactions between CR and the surface of SWNTs. The aim of the study was to explain the mechanism of this interaction. The interaction of CR and carbon nanotubes was studied using spectral analysis of the SWNT–CR complex, dynamic light scattering (DLS), differential scanning calorimetry (DSC) and microscopic methods: atomic force microscopy (AFM), transmission (TEM), scanning (SEM) and optical microscopy. The results indicate that the binding of supramolecular CR structures to the surface of the nanotubes is based on the "face to face stacking". CR molecules attached directly to the surface of the nanotubes can bind further, parallel-oriented molecules and form supramolecular and protruding structures. This explains the high CR binding capacity of carbon nanotubes. The presented system – containing SWNTs covered with CR – offers a wide range of biomedical applications.

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Alignment and Deposition of Single Wall Carbon Nanotubes under the Influence of an Electric Field

MRS Proceedings ◽

10.1557/proc-741-j8.5 ◽

2002 ◽

Vol 741 ◽

Author(s):

Paul Jaynes ◽

Thomas Tiano ◽

Margaret Roylance ◽

Charles Carey ◽

Kenneth McElrath

Keyword(s):

Carbon Nanotubes ◽

Electric Field ◽

Electronic Devices ◽

Physical And Mechanical Properties ◽

Single Wall Carbon Nanotubes ◽

Enabling Technology ◽

Single Wall Carbon ◽

Nanoelectronic Devices ◽

Wide Range ◽

Field Lines

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Thin Graphene–Nanotube Films for Electronic and Photovoltaic Devices: DFTB Modeling

Membranes ◽

10.3390/membranes10110341 ◽

2020 ◽

Vol 10 (11) ◽

pp. 341

Author(s):

Dmitry A. Kolosov ◽

Vadim V. Mitrofanov ◽

Michael M. Slepchenkov ◽

Olga E. Glukhova

Keyword(s):

Carbon Nanotubes ◽

Absorption Spectrum ◽

Energy Gap ◽

Composite Films ◽

Single Wall Carbon Nanotubes ◽

Photovoltaic Devices ◽

Optical Range ◽

Single Wall Carbon ◽

Wide Range ◽

Irregular Arrangement

Supercell atomic models of composite films on the basis of graphene and single-wall carbon nanotubes (SWCNTs) with an irregular arrangement of SWCNTs were built. It is revealed that composite films of this type have a semiconducting type of conductivity and are characterized by the presence of an energy gap of 0.43–0.73 eV. It was found that the absorption spectrum of composite films contained specific peaks in a wide range of visible and infrared (IR) wavelengths. On the basis of calculated composite films volt-ampere characteristics (VAC), the dependence of the current flowing through the films on the distance between the nanotubes was identified. For the investigated composites, spectral dependences of the photocurrent were calculated. It was shown that depending on the distance between nanotubes, the maximum photocurrent might shift from the IR to the optical range.

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Neutron Spectroscopy of Carbon nano-Materials

MRS Proceedings ◽

10.1557/proc-840-q2.3 ◽

2004 ◽

Vol 840 ◽

Author(s):

Alexander I. Kolesnikov ◽

Chun-K. Loong ◽

Alexander P. Moravsky ◽

Raouf O. Loutfy ◽

Christian J. Burnham

Keyword(s):

Carbon Nanotubes ◽

Carbon Nanotube ◽

Inelastic Neutron Scattering ◽

Inelastic Neutron ◽

Single Wall Carbon Nanotubes ◽

Single Wall Carbon ◽

Carbon Nanohorns ◽

Wide Range ◽

Single Wall Carbon Nanohorns ◽

Double Wall

ABSTRACTVibrational spectra for single wall carbon nanotubes, double wall carbon nanotubes, single wall carbon nanohorns and C60-peapods have been measured with inelastic neutron scattering in a wide range of energy transfer, 5–220 meV. A decrease in intensity around 75–100 meV and the appearance of two peaks around 120–125 meV and 150 meV in the double wall nanotubes and C60-peapods spectra compared to single wall carbon nanotubes and nanohorns were observed. These findings indicate the possibility of strong interaction between the walls of the double wall carbon nanotube, and between C60 molecules and carbon nanotube of the peapod. Alternatively, a possible contamination of the samples by hydrogen (even in microscopic quantities) covalently bonded to the carbon also can account for the observed phenomena.

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