Biological Functionalization of Carbon Nanotubes

AbstractCarbon nanotubes are known for their exceptional mechanical and unique electronic properties. The size dependant properties of nanomaterials have made them attractive to develop highly sensitive sensors and detection systems. This is especially true in biological sciences, where the efficiency of detection systems reflect on the size of the detector and the sample required for detection. At approximately 1.5 to 10nm wide, and approximately 1.5 to 2μm long, the use of carbon nanotubes as sensors in biological systems would greatly increase the sensitivity of detection and diagnostics, for a reduced sample size consisting of few individual proteins and antibodies. Since all the atoms in carbon nanotubes are surface atoms, binding proteins or antibodies to the surfaces can greatly affect their surface states, and thus their electrical and optical properties. This effect can be exploited as a basis for detecting biological surface reactions in a single protein or antibody attached to carbon nanotube surfaces.In this paper, we show the binding of fluorescently tagged antibodies in phosphate buffered saline on the surfaces of carbon nanotubes. Investigations using a confocal microscope suggest a significant interaction of the antibodies with the surfaces of the nanotubes, the intensity depending on incubation time. Since the surface area to volume ratio of CNTs is high, the use of surfactant to separate the nanotubes creates a greater surface area for antibody attachment. The interaction between CNTs and antibodies is seen to be primarily due to adsorptive surface phenomenon, between the nanotube sidewalls and antibody molecule clusters.

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Growth of Carbon Nanotubes on Carbon Toray Paper for Bio-Fuel Cell Applications

ASME 2007 2nd Energy Nanotechnology International Conference ◽

10.1115/enic2007-45038 ◽

2007 ◽

Cited By ~ 1

Author(s):

Bhupesh Chandra ◽

Joshua T. Kace ◽

Yuhao Sun ◽

S. C. Barton ◽

James Hone

Keyword(s):

Carbon Nanotubes ◽

Fuel Cell ◽

Surface Area ◽

High Surface ◽

High Surface Area ◽

Multiwall Carbon Nanotubes ◽

Volume Ratio ◽

Carbon Paper ◽

Heating Process ◽

Scale Production

In recent years carbon nanotubes have emerged as excellent materials for applications in which high surface area is required e.g. gas sensing, hydrogen storage, solar cells etc. Ultra-high surface to volume ratio is also a desirable property in the applications requiring enhanced catalytic activity where these high surface area materials can act as catalyst supports. One of the fastest developing areas needing such materials is fuel-cell. Here we investigate the process through which carbon nanotubes can be manufactured specifically to be used to increase the surface area of a carbon paper (Toray™). This carbon support is used in bio-catalytic fuel cell as an electrode to support enzyme which catalyzes the redox reaction. Deposition of nanotubes on these carbon fibers can result in great enhancement in the overall surface area to support the enzyme, which increases the reaction rate inside the fuel cell. The present paper describes a method to achieve ultra-thick growth of multiwall carbon nanotubes (MWNT) on a carbon Toray™ paper using a joule heating process and gas-phase catalyst. Using this method, we are able to achieve rapid, high-density, and uniform MWNT growth. This method is also potentially scalable toward larger-scale production.

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The Role of Temperature on the Degree of End-Closing and Filling of Single-Walled Carbon Nanotubes

Nanomaterials ◽

10.3390/nano11123365 ◽

2021 ◽

Vol 11 (12) ◽

pp. 3365

Author(s):

Magdalena Kierkowicz ◽

Elzbieta Pach ◽

Julio Fraile ◽

Concepción Domingo ◽

Belén Ballesteros ◽

...

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Surface Area ◽

Density Functional ◽

Annealing Temperature ◽

High Surface ◽

High Surface Area ◽

Volume Ratio ◽

Density Functional Theory Calculations ◽

Nitrogen Adsorption

Carbon nanotubes (CNTs), owing to their high surface area-to-volume ratio and hollow core, can be employed as hosts for adsorbed and/or encapsulated molecules. At high temperatures, the ends of CNTs close spontaneously, which is relevant for several applications, including catalysis, gas storage, and biomedical imaging and therapy. This study highlights the influence of the annealing temperature in the range between 400 and 1100 °C on the structure and morphology of single-walled CNTs. The nitrogen adsorption and density functional theory calculations indicate that the fraction of end-closed CNTs increases with temperature. Raman spectroscopy reveals that the thermal treatment does not alter the tubular structure. Insight is also provided into the efficacy of CNTs filling from the molten phase, depending on the annealing temperature. The CNTs are filled with europium (III) chloride and analyzed by using electron microscopy (scanning electron microscopy and high-resolution transmission electron microscopy) and energy-dispersive X-ray spectroscopy, confirming the presence of filling and closed ends. The filling yield increases with temperature, as determined by thermogravimetric analysis. The obtained results show that the apparent surface area of CNTs, fraction of closed ends, and amount of encapsulated payload can be tailored via annealing.

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Non-Covalent Functionalization of Carbon Nanotubes for Electrochemical Biosensor Development

Sensors ◽

10.3390/s19020392 ◽

2019 ◽

Vol 19 (2) ◽

pp. 392 ◽

Cited By ~ 52

Author(s):

Yan Zhou ◽

Yi Fang ◽

Ramaraja Ramasamy

Keyword(s):

Carbon Nanotubes ◽

Physical Adsorption ◽

Volume Ratio ◽

Biofuel Cell ◽

Electrochemical Biosensors ◽

Cylindrical Shape ◽

Covalent Functionalization ◽

Polymer Encapsulation ◽

Good Biocompatibility ◽

Functionalization Of Carbon Nanotubes

Carbon nanotubes (CNTs) have been widely studied and used for the construction of electrochemical biosensors owing to their small size, cylindrical shape, large surface-to-volume ratio, high conductivity and good biocompatibility. In electrochemical biosensors, CNTs serve a dual purpose: they act as immobilization support for biomolecules as well as provide the necessary electrical conductivity for electrochemical transduction. The ability of a recognition molecule to detect the analyte is highly dependent on the type of immobilization used for the attachment of the biomolecule to the CNT surface, a process also known as biofunctionalization. A variety of biofunctionalization methods have been studied and reported including physical adsorption, covalent cross-linking, polymer encapsulation etc. Each method carries its own advantages and limitations. In this review we provide a comprehensive review of non-covalent functionalization of carbon nanotubes with a variety of biomolecules for the development of electrochemical biosensors. This method of immobilization is increasingly being used in bioelectrode development using enzymes for biosensor and biofuel cell applications.

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FUNCTIONALIZATION OF CARBON NANOTUBES FOR MESENCHYMAL STEM CELL-ASSISTED PHOTOTHERMAL THERAPY

10.37099/mtu.dc.etd-restricted/233 ◽

2014 ◽

Author(s):

Ethan J. Weydemeyer

Keyword(s):

Carbon Nanotubes ◽

Stem Cell ◽

Mesenchymal Stem Cell ◽

Photothermal Therapy ◽

Functionalization Of Carbon Nanotubes

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Evaluation of Nanotechniques and Conventional Techniques for the Removal of Dioxins

Nanoscience &Nanotechnology-Asia ◽

10.2174/2210681208666180110153919 ◽

2018 ◽

Vol 9 (1) ◽

pp. 79-84

Author(s):

Vaishali V. Shahare ◽

Rajni Grover ◽

Suman Meena

Keyword(s):

Soil Sample ◽

Human Health ◽

Surface Area ◽

Contaminated Soil ◽

Conventional Treatment ◽

Volume Ratio ◽

Soil Samples ◽

Dioxins And Furans ◽

Palladized Iron ◽

The Impact

Background: The persistent dioxins/furans has caused a worldwide concern as they influence the human health. Recent research indicates that nonmaterial may prove effective in the degradation of Dioxins/furans. The nanomaterials are very reactive owing to their large surface area to volume ratio and large number of reactive sites. However, nanotechnology applications face both the challenges and the opportunities to influence the area of environmental protection. Objective: i) To study the impact of oil mediated UV-irradiations on the removal of 2,3,7,8-TCDD, 2,3,7,8-TCDF, OCDD and OCDF in simulated soil samples. ii) To compare the conventional treatment methods with the modern available nanotechniques for the removal of selected Dioxins/furans from soil samples. Methods: The present work has investigated an opportunity of the degradation of tetra and octachlorinated dioxins and furans by using oil mediated UV radiations with subsequent extraction of respective dioxins/furans from soils. The results have been compared with the available nanotechniques. Results: The dioxin congeners in the simulated soil sample showed decrease in concentration with the increase in the exposure time and intensity of UV radiations. The dechlorination of PCDD/Fs using palladized iron has been found to be effective. Conclusion: Both the conventional methods and nanotechnology have a dramatic impact on the removal of Dioxins/furans in contaminated soil. However, the nanotechniques are comparatively costlier and despite the relatively high rates of PCDDs dechlorination by Pd/nFe, small fraction of the dioxins are recalcitrant to degradation over considerable exposure times.

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Clicked Bifunctional Dendrimeric and Cyclopeptidic Addressable Redox Scaffolds for the Functionalization of Carbon Nanotubes with Redox Molecules and Enzymes

Langmuir ◽

10.1021/acs.langmuir.0c02095 ◽

2021 ◽

Vol 37 (3) ◽

pp. 1001-1011

Author(s):

Solène Gentil ◽

Carlo Pifferi ◽

Pierre Rousselot-Pailley ◽

Thierry Tron ◽

Olivier Renaudet ◽

...

Keyword(s):

Carbon Nanotubes ◽

Functionalization Of Carbon Nanotubes ◽

Redox Molecules

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Precise regulation of the relative rates of surface area and volume synthesis in bacterial cells growing in dynamic environments

Nature Communications ◽

10.1038/s41467-021-22092-5 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Handuo Shi ◽

Yan Hu ◽

Pascal D. Odermatt ◽

Carlos G. Gonzalez ◽

Lichao Zhang ◽

...

Keyword(s):

Growth Rate ◽

Time Delay ◽

Surface Area ◽

Environmental Changes ◽

Volume Ratio ◽

Dynamic Environments ◽

Bacterial Cells ◽

Bacterial Growth Rate ◽

State Size ◽

Insight Into

AbstractThe steady-state size of bacterial cells correlates with nutrient-determined growth rate. Here, we explore how rod-shaped bacterial cells regulate their morphology during rapid environmental changes. We quantify cellular dimensions throughout passage cycles of stationary-phase cells diluted into fresh medium and grown back to saturation. We find that cells exhibit characteristic dynamics in surface area to volume ratio (SA/V), which are conserved across genetic and chemical perturbations as well as across species and growth temperatures. A mathematical model with a single fitting parameter (the time delay between surface and volume synthesis) is quantitatively consistent with our SA/V experimental observations. The model supports that this time delay is due to differential expression of volume and surface-related genes, and that the first division after dilution occurs at a tightly controlled SA/V. Our minimal model thus provides insight into the connections between bacterial growth rate and cell shape in dynamic environments.

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