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Journal ArticleDOI

Band gap fluorescence from individual single-walled carbon nanotubes.

TLDR
At pH less than 5, the absorption and emission spectra of individual nanotubes show evidence of band gap–selective protonation of the side walls of the tube, which is readily reversed by treatment with base or ultraviolet light.
Abstract
Fluorescence has been observed directly across the band gap of semiconducting carbon nanotubes. We obtained individual nanotubes, each encased in a cylindrical micelle, by ultrasonically agitating an aqueous dispersion of raw single-walled carbon nanotubes in sodium dodecyl sulfate and then centrifuging to remove tube bundles, ropes, and residual catalyst. Aggregation of nanotubes into bundles otherwise quenches the fluorescence through interactions with metallic tubes and substantially broadens the absorption spectra. At pH less than 5, the absorption and emission spectra of individual nanotubes show evidence of band gap-selective protonation of the side walls of the tube. This protonation is readily reversed by treatment with base or ultraviolet light.

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Single-walled carbon nanotubes as a multimodal-thermoacoustic and photoacoustic-contrast agent.

TL;DR: A novel carbon nanotube-based contrast agent for both thermoacoustic and photoacoustic tomography with large contrast enhancement was developed and corroborated by tissue phantom imaging studies.
Journal ArticleDOI

Double-Stranded DNA Single-Walled Carbon Nanotube Hybrids for Optical Hydrogen Peroxide and Glucose Sensing

TL;DR: The redox chemistry of SWNTs encased with double-stranded deoxyribonucleic acid (DNA) reacted with either hydrogen peroxide H2O2 or glucose in the presence of the glucose oxidase enzyme is studied.
Journal ArticleDOI

Nanostructured scaffolds for neural applications.

TL;DR: This review will highlight several techniques that are used to create nanostructured scaffolds, such as photolithography to create grooves for neurite guidance, electrospinning of fibrous matrices, self-assembly of 3D scaffolds from designer peptides and fabrication of conductive nanoscale materials.
Journal ArticleDOI

Crucial Functionalizations of Carbon Nanotubes for Improved Drug Delivery: A Valuable Option?

TL;DR: This expert review aims to evaluate whether this innovative material, once chemically-modified with suitable functionalizations, can be considered as a valuable system in comparison to the already existing nanodevices.
Journal ArticleDOI

Purity assessment of single-wall carbon nanotubes, using optical absorption spectroscopy.

TL;DR: A simple protocol for purity assessment of laser and arc-discharge SWNTs has been established that can be extended to other synthetic types and diameter distributions, and has enabled corroboration of rapid assessment procedures, such as absorbance peak maxima ratio and Beer's law analysis.
References
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Journal ArticleDOI

CHARMM: A program for macromolecular energy, minimization, and dynamics calculations

TL;DR: The CHARMM (Chemistry at Harvard Macromolecular Mechanics) as discussed by the authors is a computer program that uses empirical energy functions to model macromolescular systems, and it can read or model build structures, energy minimize them by first- or second-derivative techniques, perform a normal mode or molecular dynamics simulation, and analyze the structural, equilibrium, and dynamic properties determined in these calculations.
Journal ArticleDOI

MOLSCRIPT: a program to produce both detailed and schematic plots of protein structures

TL;DR: The MOLSCRIPT program as discussed by the authors produces plots of protein structures using several different kinds of representations, including simple wire models, ball-and-stick models, CPK models and text labels.
Journal ArticleDOI

Crystalline Ropes of Metallic Carbon Nanotubes

TL;DR: X-ray diffraction and electron microscopy showed that fullerene single-wall nanotubes (SWNTs) are nearly uniform in diameter and that they self-organize into “ropes,” which consist of 100 to 500 SWNTs in a two-dimensional triangular lattice with a lattice constant of 17 angstroms.
Book

Science of fullerenes and carbon nanotubes

TL;DR: In this paper, the authors present a detailed overview of the properties of Fullerenes and their properties in surface science applications, such as scanning tunnel microscopy, growth and fragmentation studies, and chemical synthesis.
Journal ArticleDOI

Constant pressure molecular dynamics simulation: The Langevin piston method

TL;DR: In this paper, a new method for performing molecular dynamics simulations under constant pressure is presented, which is based on the extended system formalism introduced by Andersen, the deterministic equations of motion for the piston degree of freedom are replaced by a Langevin equation; a suitable choice of collision frequency then eliminates the unphysical "ringing" of the volume associated with the piston mass.
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