Author: Elzbieta Pach
Publisher:
ISBN: 9788449074332
Category :
Languages : en
Pages : 256

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Book Description
La presente tesis doctoral se centra en el estudio exhaustivo de nanotubos de carbono funcionales por medio de técnicas de microscopía electrónica. Los nanotubos de carbono (CNTs) funcionales están atrayendo una creciente atención debido a su potencial uso para aplicaciones biomédicas, incluyendo para la adquisición de imágenes in vivo, acumulación selectiva en tumores y sistemas de administración de fármacos. Una ventaja intrínseca de los nanotubos de carbono es que su cavidad interna puede llenarse con una carga útil de interés mientras que la superficie externa puede modificarse para mejorar su dispersabilidad y biocompatibilidad. Debido a su potencial aplicación en el campo biomédico, es esencial una caracterización detallada de las muestras en todas las etapas de su proceso de preparación (purificación, acortamiento, llenado y funcionalidad externa). Para lograr este objetivo, en esta tesis doctoral hemos empleado tanto los análisis ya establecidos que incluye microscopía electrónica de transmisión de alta resolución para estudiar la estructura del material de relleno o espectroscopia de dispersión de energía de rayos X para evaluar su composición, pero también hemos explorado el uso de otras técnicas para ampliar las posibilidades de caracterización de las muestras. En este sentido, hemos optimizado las condiciones para el estudio de las longitudes de CNTs monocapa purificados por microscopía electrónica de barrido de alta resolución (HRSEM) con sensibilidad superficial. Además, la microscopía electrónica de transmisión y barrido (STEM) a bajos voltajes se ha demostrado como una técnica eficiente y rápida para evaluar el rendimiento del rellenado y la pureza del material. De hecho, la combinación de alta resolución espacial y el trabajo a bajos voltajes de esta técnica la ha hecho particularmente adecuada para el estudio de la interacción de nanotubos de carbono funcionales con muestras biológicas, como por ejemplo células. Algunos de los compuestos con interés para aplicaciones biomédicas empleados en este trabajo tienen una estructura laminar. Se sabe que los materiales laminares forman monocapas que pueden tener propiedades mejoradas o nuevas debido a efectos de confinamiento. Los CNT pueden actuar como plantillas para guiar los materiales laminares a formar nanotubos monocapa. Este es el caso de los haluros de lutecio y el yoduro de plomo. En esta tesis de doctorado hemos conseguido la formación de nanotubos de haluros de lutecio de tamaño subnanométrico, y su naturaleza tubular se ha demostrado mediante STEM con corrector de aberraciones y simulaciones de imagen. Además, se ha logrado el crecimiento con alto rendimiento de nanotubos de PbI2 en el exterior de CNTs. La estructura de los híbridos se ha revelado mediante STEM con aberración corregida y tomografía electrónica. Cabe destacar que las propiedades ópticas de los híbridos difieren de las del PbI2 en masa. El desplazamiento azul observado por fotoluminiscencia se ha confirmado mediante análisis en híbridos PbI2-CNT individuales por catodoluminiscencia-STEM. En conclusión, durante este proyecto de doctorado la gama de técnicas de microscopía electrónica utilizadas para el estudio de CNT funcionales se ha ampliado para obtener una caracterización exhaustiva de las muestras.

Author: Zhong-lin Wang
Publisher: Springer Science & Business Media
ISBN: 1461503159
Category : Technology & Engineering
Languages : en
Pages : 315

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Book Description
Written by prominent scientists, this book is the first to specifically address the theory, techniques, and application of electron microscopy and associated techniques for nanotube research, a topic that is impacting a variety of fields, such as nanoelectronics, flat panel display, nanodevices, and novel instrumentation.

Author: Huisheng Peng
Publisher: William Andrew
ISBN: 0323415318
Category : Technology & Engineering
Languages : en
Pages : 510

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Book Description
Industrial Applications of Carbon Nanotubes covers the current applications of carbon nanotubes in various industry sectors, from the military to visual display products, and energy harvesting and storage. It also assesses the opportunities and challenges for increased commercialization and manufacturing of carbon nanotubes in the years ahead. Real-life case studies illustrate how carbon nanotubes are used in each industry sector covered, providing a valuable resource for scientists and engineers who are involved and/or interested in carbon nanotubes in both academia and industry. The book serves as a comprehensive guide to the varied uses of carbon nanotubes for specialists in many related fields, including chemistry, physics, biology, and textiles. Explains how carbon nanotubes can be used to improve the efficiency and performance of industrial products Includes real-life case studies to illustrate how carbon nanotubes have been successfully employed Explores how carbon nanotubes could be mass-manufactured in the future, and outlines the challenges that need to be overcome

Author: Mingqi Liu
Publisher:
ISBN:
Category : Carbon
Languages : en
Pages : 454

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Book Description

Author: Patrick Bernier
Publisher:
ISBN:
Category : Technology & Engineering
Languages : en
Pages : 416

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Book Description
The MRS Symposium Proceeding series is an internationally recognised reference suitable for researchers and practitioners. This book, first published in 2002, focuses on the design, production and understanding of nanotube-based materials, structures, and devices.

Author: M. Endo
Publisher: Elsevier
ISBN: 008054553X
Category : Science
Languages : en
Pages : 200

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Book Description
Carbon nanotubes have been studied extensively in relation to fullerenes, and together with fullerenes have opened a new science and technology field on nano scale materials. A whole range of issues from the preparation, structure, properties and observation of quantum effects in carbon nanotubes in comparison with 0-D fullerenes are discussed. In addition, complementary reviews on carbon nanoparticles such as carbon nano-capsules, onion-like graphite particles and metal-coated fullerenes are covered. This book aims to cover recent research and development in this area, and so provide a convenient reference tool for all researchers in this field. It is also hoped that this book can serve to stimulate future work on carbon nanotubes.

Author: Michio Inagaki
Publisher: Butterworth-Heinemann
ISBN: 0128054689
Category : Technology & Engineering
Languages : en
Pages : 340

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Book Description
Materials Science and Engineering of Carbon: Characterization discusses 12 characterization techniques, focusing on their application to carbon materials, including X-ray diffraction, X-ray small-angle scattering, transmission electron microscopy, Raman spectroscopy, scanning electron microscopy, image analysis, X-ray photoelectron spectroscopy, magnetoresistance, electrochemical performance, pore structure analysis, thermal analyses, and quantification of functional groups. Each contributor in the book has worked on carbon materials for many years, and their background and experience will provide guidance on the development and research of carbon materials and their further applications. Focuses on characterization techniques for carbon materials Authored by experts who are considered specialists in their respective techniques Presents practical results on various carbon materials, including fault results, which will help readers understand the optimum conditions for the characterization of carbon materials

Author: Kazuyoshi Tanaka
Publisher: Newnes
ISBN: 0080982689
Category : Science
Languages : en
Pages : 458

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Book Description
Carbon Nanotubes and Graphene is a timely second edition of the original Science and Technology of Carbon Nanotubes. Updated to include expanded coverage of the preparation, purification, structural characterization, and common application areas of single- and multi-walled CNT structures, this work compares, contrasts, and, where appropriate, unitizes CNT to graphene. This much expanded second edition reference supports knowledge discovery, production of impactful carbon research, encourages transition between research fields, and aids the formation of emergent applications. New chapters encompass recent developments in the theoretical treatments of electronic and vibrational structures, and magnetic, optical, and electrical solid-state properties, providing a vital base to research. Current and potential applications of both materials, including the prospect for large-scale synthesis of graphene, biological structures, and flexible electronics, are also critically discussed. Updated discussion of properties, structure, and morphology of biological and flexible electronic applications aids fundamental knowledge discovery Innovative parallel focus on nanotubes and graphene enables you to learn from the successes and failures of, respectively, mature and emergent partner research disciplines High-quality figures and tables on physical and mathematical applications expertly summarize key information – essential if you need quick, critically relevant data

Author: Cédric Klumpp
Publisher:
ISBN:
Category :
Languages : en
Pages : 175

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Book Description
Fullerenes and carbon nanotubes are new allotropes of carbon discovered in 1985 and 1991 respectively. Fullerenes are spheres of few angströms theoretically constituted of at least 20 carbon atoms. The most stable and abundant isomer is the C60 which is formed of 12 pentagons and 20 hexagons. Carbon nanotubes are basically a rolled sheet of graphite terminated by two end caps similar to a half C60. Two main types of nanotubes exist: i) the single-walled carbon nanotubes which are composed by a rolled monolayered graphene sheet, and ii) the multi-walled carbon nanotubes which possess several graphitic concentric layers. The different chemical and physical properties of fullerenes and carbon nanotubes allowed finding already applications in the field of material sciences. Nevertheless, the search on their potential applications in the biological or medical field is still little explored. The different laboratories where I conducted my thesis are specialized in the development of fullerene and carbon nanotubes derivatives for therapeutics purposes. During my PhD thesis, I focused my interests on the functionalization and the characterization of fullerenes and carbon nanotubes and their potential biological applications. Nowadays, the characterization of functionalized nanotubes remains very complicate because the current techniques does not allow establishing simultaneously the presence of the carbon nanotubes, the presence of functional groups and the presence of covalent bonding between the tube and the functional moiety. Several techniques were therefore used like the nuclear magnetic resonance, the transmission electron microscopy, the atomic force microscopy and the thermogravimetry analysis to gather a maximum of data on the functionalized nanotubes. We studied then the biodistribution and elimination of functionalized carbon nanotubes in vivo. For this purpose, single or multiwalled carbon nanotubes were functionalized with the radiotracer indium 111. The conjugates were then injected in mice and the radioactivity was measured in the different organs after 30 minutes, 3 hours and 24 hours. Radioactivity was detected in every organ after 30 minutes and almost disappeared after 24 hours. These results indicated that the nanotube elimination process was fast. Moreover, transmission electron microscopy analysis of the urine revealed that the carbon nanotubes were eliminated via the renal excretion. No signs of toxicity were detected on the mice, meaning that functionalized nanotubes are biocompatible. Thus, we envisaged to use the carbon nanotubes as new vectors for therapeutic molecules. Amphotericin B was linked onto the surface of the carbon nanotubes and the conjugates were tested on several strains of fungi and on mammalian cells as well. It appeared that the carbon nanotube conjugates were more potent than the drug alone against the fungi and allowed also reducing the toxicity of the amphotericin B on mammalian cells. Alternatively, we explored the use of fullerene as potential vector systems. We described the synthesis and characterization of multi-functionalized fullerene derivatives. In this context, the 1,3-dipolar cycloaddition reaction of azomethine ylides was applied to obtain functionalized fullerene bearing a distribution of organic moieties around the spherical cage. Their characterization was realized by several techniques such as high pressure liquid chromatography, mass spectrometry and nuclear magnetic resonance. Moreover, the introduction of ammonium groups on the surface of C60 greatly increased the solubility in aqueous media. The linkage of a fluorescent probe on the fullerene derivatives permitted to evaluate by flow cytometry and confocal microscopy their biological compatibility and their potential to cross the plasma membrane. Secondly, warfarin, an anticoagulant molecule, was attached in order to use the fullerene derivatives as a drug delivery system and to determine if a multi-presentation of the biomolecule could enhance its effect. Previously, we reported the capacity of nanotubes to act as gene vectors. Thus, polycationic fullerenes were prepared to evaluate their ability to complex DNA. The complexes were characterized by gel electrophoresis and transmission electron microscopy. In addition, surface plasmon resonance allowed measuring the affinity constant. The fullerene derivatives are potentially able to deliver DNA inside the cells. In order to verify this hypothesis, gene transfer studies have already started.In conclusion, the preparation of functionalized carbon nanotubes and fullerenes for biological applications was reported. Notably, carbon nanotubes derivatives are non-toxic and can deliver antifungal molecules and modulate their cytotoxic effects. In the same way, fullerene derivatives were able to penetrate the plasma membrane without provoking cytotoxicity and to strongly complex plasmid DNA. Therefore, they could be used as a potential vector for gene and drug delivery. Finally, functionalized carbon-based nanomaterials can be considered an efficient alternative system for the delivery of therapeutics and may find interesting future biomedical applications.

Author: Rüdiger Klingeler
Publisher: Springer Science & Business Media
ISBN: 3642148026
Category : Technology & Engineering
Languages : en
Pages : 286

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Book Description
This book explores the potential of multi-functional carbon nanotubes for biomedical applications. It combines contributions from chemistry, physics, biology, engineering, and medicine. The complete overview of the state-of-the-art addresses different synthesis and biofunctionalisation routes and shows the structural and magnetic properties of nanotubes relevant to biomedical applications. Particular emphasis is put on the interaction of carbon nanotubes with biological environments, i.e. toxicity, biocompatibility, cellular uptake, intracellular distribution, interaction with the immune system and environmental impact. The insertion of NMR-active substances allows diagnostic usage as markers and sensors, e.g. for imaging and contactless local temperature sensing. The potential of nanotubes for therapeutic applications is highlighted by studies on chemotherapeutic drug filling and release, targeting and magnetic hyperthermia studies for anti-cancer treatment at the cellular level.