31 results on '"Calum Kinnear"'
Search Results
2. A General Method for Direct Assembly of Single Nanocrystals
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Heyou Zhang, Yawei Liu, Arun Ashokan, Can Gao, Yue Dong, Calum Kinnear, Nicholas Kirkwood, Samantha Zaman, Fatemeh Maasoumi, Timothy D. James, Asaph Widmer‐Cooper, Ann Roberts, and Paul Mulvaney
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Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials - Published
- 2022
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Catalog
3. Enhanced Photoelectrocatalysis Using a Bimetallic Plasmonic Near-Perfect Absorber
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Qi Xiao, CALUM KINNEAR, Timothy U. Connell, Muhammad Kalim Kashif, Christopher D. Easton, Aaron Seeber, Laure Bourgeois, Gus O. Bonin, Noel W. Duffy, Anthony S. R. Chesman, and Daniel E. Gómez
- Abstract
In this paper, we developed the fabrication of a plasmonic near-perfect absorber with a dense, uniform monolayer of AuPd alloyed nanoparticles as the absorbing layer. The nanoparticles were prepared by dewetting thin films ( more...
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- 2020
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4. Direct Assembly of Large Area Nanoparticle Arrays
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Calum Kinnear, Paul Mulvaney, Ann Roberts, Heyou Zhang, Timothy D. James, and Jasper J. Cadusch
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Nanostructure ,General Engineering ,General Physics and Astronomy ,Nanoparticle ,Nanotechnology ,02 engineering and technology ,Substrate (electronics) ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Electrophoretic deposition ,General Materials Science ,Nanorod ,Nanometre ,0210 nano-technology ,Nanoscopic scale ,Plasmon - Abstract
A major goal of nanotechnology is the assembly of nanoscale building blocks into functional optical, electrical, or chemical devices. Many of these applications depend on an ability to optically or electrically address single nanoparticles. However, positioning large numbers of single nanocrystals with nanometer precision on a substrate for integration into solid-state devices remains a fundamental roadblock. Here, we report fast, scalable assembly of thousands of single nanoparticles using electrophoretic deposition. We demonstrate that gold nanospheres down to 30 nm in size and gold nanorods more...
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- 2018
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5. Directed Chemical Assembly of Single and Clustered Nanoparticles with Silanized Templates
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Calum Kinnear, Jianing Lu, Paul Mulvaney, Timothy D. James, Heyou Zhang, Ann Roberts, and Jasper J. Cadusch
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Nanostructure ,Materials science ,Nanoparticle ,Nanotechnology ,02 engineering and technology ,Surfaces and Interfaces ,Carbon nanotube ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Nanoimprint lithography ,law.invention ,Template ,law ,Colloidal gold ,Electrochemistry ,General Materials Science ,Nanorod ,0210 nano-technology ,Lithography ,Spectroscopy - Abstract
The assembly of nanoscale materials into arbitrary, organized structures remains a major challenge in nanotechnology. Herein, we report a general method for creating 2D structures by combining top-down lithography with bottom-up chemical assembly. Under optimal conditions, the assembly of gold nanoparticles was achieved in less than 30 min. Single gold nanoparticles, from 10 to 100 nm, can be placed in predetermined patterns with high fidelity, and higher-order structures can be generated consisting of dimers or trimers. It is shown that the nanoparticle arrays can be transferred to, and embedded within, polymer films. This provides a new method for the large-scale fabrication of nanoparticle arrays onto diverse substrates using wet chemistry. more...
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- 2018
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6. Snapshot Hyperspectral Imaging (SHI) for Revealing Irreversible and Heterogeneous Plasmonic Processes
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Kyle W. Smith, Christy F. Landes, Calum Kinnear, Sean S. E. Collins, Heyou Zhang, Wenxiao Wang, Silke R. Kirchner, Yi-Yu Cai, Paul Mulvaney, Stephan Link, Benjamin S. Hoener, and Wei-Shun Chang
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Diffraction ,Plasmonic nanoparticles ,Scattering ,business.industry ,Physics::Optics ,Hyperspectral imaging ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Supercontinuum ,Metrology ,General Energy ,Optoelectronics ,Physical and Theoretical Chemistry ,Spectral resolution ,0210 nano-technology ,business ,Plasmon - Abstract
Plasmon-mediated processes provide unique opportunities for selective photocatalysis, photovoltaics, and electrochemistry. Determining the influence of particle heterogeneity is an unsolved problem because often such processes introduce irreversible changes to the nanocatalysts and/or their surroundings. The challenge lies in monitoring heterogeneous nonequilibrium dynamics via the slow, serial methods that are intrinsic to almost all spectral acquisition methods with suitable spatial and/or spectral resolution. Here, we present a new metrology, snapshot hyperspectral imaging (SHI), that facilitates in situ readout of the tube lens image and first-order diffraction image of the dark-field scattering from many individual plasmonic nanoparticles to extract their respective spectra simultaneously. Evanescent wave excitation with a supercontinuum laser enabled signal-to-noise ratios greater than 100 with a time resolution of only 1 ms. Throughput of ∼100 simultaneous spectra was achieved with a highly ordered... more...
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- 2018
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7. Fabrication of Single-Nanocrystal Arrays
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Calum Kinnear, Paul Mulvaney, and Heyou Zhang
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Fabrication ,Materials science ,Mechanical Engineering ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Nanoimprint lithography ,law.invention ,Electrophoretic deposition ,Nanolithography ,Nanocrystal ,Mechanics of Materials ,law ,General Materials Science ,Nanorod ,0210 nano-technology ,Lithography ,Electron-beam lithography - Abstract
To realize the full potential of nanocrystals in nanotechnology, it is necessary to integrate single nanocrystals into addressable structures; for example, arrays and periodic lattices. The current methods for achieving this are reviewed. It is shown that a combination of top-down lithography techniques with directed assembly offers a platform for attaining this goal. The most promising of these directed assembly methods are reviewed: capillary force assembly, electrostatic assembly, optical printing, DNA-based assembly, and electrophoretic deposition. The last of these appears to offer a generic approach to fabrication of single-nanocrystal arrays. more...
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- 2019
8. Particokinetics and in vitro dose of high aspect ratio nanoparticles
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Calum Kinnear, Sandor Balog, and Seth Richard Price
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Nanoparticle ,Metal Nanoparticles ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Models, Biological ,In vitro ,0104 chemical sciences ,3. Good health ,Kinetics ,Adherent cell ,Nanofiber ,Nanoparticles ,General Materials Science ,Nanorod ,Gold ,0210 nano-technology ,Metal nanoparticles ,Cellulose - Abstract
Computational particokinetics models become essential in the design and interpretation of in vitro nanoparticle toxicology assays involving submerged adherent cell cultures. Yet, none of the current models offers the possibility of addressing the delivered dose of high-aspect ratio nanoparticles, including nanorods, nanotubes, and nanofibers. Here we present a straightforward method that lends this ability to any of the models used currently. more...
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- 2019
9. Assumption-free morphological quantification of single anisotropic nanoparticles and aggregates
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Laura Rodriguez-Lorenzo, Estelle Durantie, Dimitri Vanhecke, Alke Petri-Fink, Calum Kinnear, and Barbara Rothen-Rutishauser
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Surface (mathematics) ,Materials science ,Anisotropic nanoparticles ,Nanoparticle ,Nanotechnology ,02 engineering and technology ,engineering.material ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Curvature ,01 natural sciences ,Fractal dimension ,0104 chemical sciences ,Electron tomography ,engineering ,General Materials Science ,Noble metal ,Segmentation ,0210 nano-technology ,Biological system - Abstract
Characterizing the morphometric parameters of noble metal nanoparticles for sensing and catalysis is a persistent challenge due to their small size and complex shape. Herein, we present an approach to determine the volume, surface area, and curvature of non-symmetric anisotropic nanoparticles using electron tomography and design- based stereology without the use of segmentation tools or modeling of the particles. Finally, we apply these tools to aggregates to estimate their fractal dimension. more...
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- 2017
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10. Direct Assembly of Vertically Oriented, Gold Nanorod Arrays
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Asaph Widmer-Cooper, Eser Metin Akinoglu, Muhammad Faris Shahin Shahidan, Ann Roberts, Calum Kinnear, Paul Mulvaney, Timothy D. James, Jasper J. Cadusch, Fatemeh Maasoumi, Yawei Liu, and Heyou Zhang
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Materials science ,business.industry ,Surface plasmon ,Physics::Optics ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,Biomaterials ,Dipole ,Electric dipole moment ,Quantum dot ,Polarizability ,Electric field ,Electrochemistry ,Optoelectronics ,Nanorod ,0210 nano-technology ,business ,Plasmon - Abstract
Although many nanoscale materials such as quantum dots and metallic nanocrystals exhibit size dependent optical properties, it has been difficult to incorporate them into optical or electronic devices because there are currently no methods for precise, large‐scale deposition of single nanocrystals. Of particular interest is the need to control the orientation of single nanocrystals since the optical properties are usually strongly anisotropic. Here a method based on electrophoretic deposition (EPD) is reported to precisely assemble vertically oriented, single gold nanorods. It is demonstrated that the orientation of gold nanorods during deposition is controlled by the electric dipole moment induced along the rod by the electric field. Dissipative particle dynamics simulations indicate that the magnitude of this dipole moment is dominated by the polarizability of the solution phase electric double layer around the nanorod. The resulting vertical gold nanorod arrays exhibit reflected colors due to selective excitation of the transverse surface plasmon mode. The EPD method allows assembly of arrays with a density of over one million, visually resolvable, vertical nanorods per square millimeter. more...
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- 2020
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11. Concealed Structural Colors Uncovered by Light Scattering
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Jingchao Song, Calum Kinnear, Ann Roberts, Paul Mulvaney, Heyou Zhang, Yafei Xue, Jürgen Köhler, and Eser Metin Akinoglu
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Materials science ,business.industry ,Scattering ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Interference (wave propagation) ,01 natural sciences ,Electromagnetic radiation ,Atomic and Molecular Physics, and Optics ,Light scattering ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,Standing wave ,Wavelength ,Optics ,Thin-film interference ,0210 nano-technology ,business ,Structural coloration - Abstract
Unusual structural colors are demonstrated in thin-film coatings due to a combination of optical interference and light scattering effects. These vivid colors are concealed under ambient illumination but can be observed when light is reflected from the film surface. The origin of the effect is explored computationally and it is shown that, in thin-films of lossless dielectrics coated on near-perfect conductors, incident electromagnetic waves form standing waves. Electric field intensities at the thin film interfaces are maximized for wavelengths that fulfil destructive interference conditions, while nanoscale roughness can enhance scattering at these boundaries. The interplay of these two factors yields vivid, thickness-dependent colors. This approach increases the repertoire of optical effects and perceived colors in thin coatings. When combined with traditional thin-film interference colours, dichromatic images with distinctly changing colors can be generated, which can function as a covert, optical security feature. more...
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- 2020
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12. Single‐Nanocrystal Arrays: Fabrication of Single‐Nanocrystal Arrays (Adv. Mater. 18/2020)
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Paul Mulvaney, Heyou Zhang, and Calum Kinnear
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Nanolithography ,Materials science ,Fabrication ,Nanocrystal ,Mechanics of Materials ,Mechanical Engineering ,General Materials Science ,Nanotechnology - Published
- 2020
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13. Practical guides for x-ray photoelectron spectroscopy: Analysis of polymers
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Calum Kinnear, Christopher D. Easton, Thomas R. Gengenbach, and Sally L. McArthur
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Profiling (computer programming) ,chemistry.chemical_classification ,Data processing ,Data collection ,business.industry ,Sample (material) ,02 engineering and technology ,Surfaces and Interfaces ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,Chemical state ,chemistry ,X-ray photoelectron spectroscopy ,Sample preparation ,0210 nano-technology ,Process engineering ,business - Abstract
XPS is widely used to identify and quantify the elements present at the surface of polymeric materials. The energy distribution of photoelectrons emitted from these elements contains information about their chemical state, potentially allowing the analyst to identify and quantify specific functional groups. These functional groups may originate from the synthesis and processing of the polymers, from postsynthetic modifications such as surface grafting, or indeed may be unrelated to the polymer (additives and contaminants). Extracting reliable and meaningful information from XPS data is not trivial and relies on careful and appropriate experimentation, including experimental design, sample preparation, data collection, data processing, and data interpretation. Here, the authors outline some of these challenges when performing XPS analysis of polymers and provide practical examples to follow. This guide will cover all relevant aspects over the course of a typical experiment, including tips and considerations when designing the experiment, sample preparation, charge neutralization, x-ray induced sample damage, depth profiling, data analysis and interpretation, and, finally, reporting of results. Many of these topics are more widely applicable to insulating organic materials, and the recommendations of this guide will help to ensure that data is collected and interpreted using current best practices. more...
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- 2020
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14. Plasmonic polymer nanocomposites
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Isabel Pastoriza-Santos, Jorge Pérez-Juste, Calum Kinnear, Paul Mulvaney, and Luis M. Liz-Marzán
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Plasmonic nanoparticles ,Nanocomposite ,Materials science ,Polymer nanocomposite ,Surface plasmon ,technology, industry, and agriculture ,Nanoparticle ,Physics::Optics ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Silver nanoparticle ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Biomaterials ,Materials Chemistry ,0210 nano-technology ,Plasmon ,Energy (miscellaneous) ,Localized surface plasmon - Abstract
The optical properties of metal nanoparticles, particularly their localized surface plasmon effects, are well established. These plasmonic nanoparticles can respond to their surroundings or even influence the optical processes (for example, absorption, fluorescence and Raman scattering) of molecules located at their surface. As a result, plasmonic nanoparticles have been developed for multiple purposes, ranging from the detection of chemicals and biological molecules to light-harvesting enhancement in solar cells. By dispersing the nanoparticles in polymers and creating a hybrid material, the robustness, responsiveness and flexibility of the system are enhanced while preserving the intrinsic properties of the nanoparticles. In this Review, we discuss the fabrication and applications of plasmonic polymer nanocomposites, focusing on applications in optical data storage, sensing and imaging and photothermal gels for in vivo therapy. Within the nanocomposites, the nanoporosity of the matrix, the overall mechanical stability and the dispersion of the nanoparticles are important parameters for achieving the best performance. In the future, translation of these materials into commercial products rests on the ability to scale up the production of plasmonic polymer nanocomposites with tailored optical features. more...
- Published
- 2018
15. Beyond Global Charge: Role of Amine Bulkiness and Protein Fingerprint on Nanoparticle-Cell Interaction
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Barbara Rothen-Rutishauser, Alke Petri-Fink, Calum Kinnear, Jörn Dengjel, Ana Milosevic, Miguel Spuch-Calvar, Sandor Balog, Thomas Moore, and David Burnand
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Nanoparticle ,Metal Nanoparticles ,Proteins ,Protein Corona ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Peptide Mapping ,0104 chemical sciences ,Biomaterials ,Adsorption ,Colloidal gold ,Copolymer ,Biophysics ,Side chain ,General Materials Science ,Amine gas treating ,Surface charge ,Gold ,Amines ,0210 nano-technology ,Biotechnology - Abstract
Amino groups presented on the surface of nanoparticles are well‐known to be a predominant factor in the formation of the protein corona and subsequent cellular uptake. However, the molecular mechanism underpinning this relationship is poorly defined. This study investigates how amine type and density affect the protein corona and cellular association of gold nanoparticles with cells in vitro. Four specific poly(vinyl alcohol‐co‐N‐vinylamine) copolymers are synthesized containing primary, secondary, or tertiary amines. Particle cellular association (i.e., cellular uptake and surface adsorption), as well as protein corona composition, are then investigated. It is found that the protein corona (as a consequence of “amine bulkiness”) and amine density are both important in dictating cellular association. By evaluating the nanoparticle surface chemistry and the protein fingerprint, proteins that are significant in mediating particle–cell association are identified. In particular, primary amines, when exposed on the polymer side chain, are strongly correlated with the presence of alpha‐2‐HS‐ glycoprotein, and promote nanoparticle cellular association. more...
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- 2018
16. Ultrathin Ceramic Membranes as Scaffolds for Functional Cell Coculture Models on a Biomimetic Scale
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Corinne Jud, Sher Ahmed, Loretta Müller, Calum Kinnear, Dimitri Vanhecke, Yuki Umehara, Sabine Frey, Martha Liley, Silvia Angeloni, Alke Petri-Fink, and Barbara Rothen-Rutishauser
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Basement membrane ,Insert (composites) ,cell culture ,Materials science ,lcsh:R ,lcsh:Medicine ,Microporous material ,General Biochemistry, Genetics and Molecular Biology ,Ceramic membrane ,medicine.anatomical_structure ,Membrane ,Tissue engineering ,lcsh:Biology (General) ,Cell culture ,visual_art ,tissue engineering ,visual_art.visual_art_medium ,medicine ,Biophysics ,Ceramic ,Original Research Article ,lcsh:QH301-705.5 ,toxicology - Abstract
Epithelial tissue serves as an interface between biological compartments. Many in vitro epithelial cell models have been developed as an alternative to animal experiments to answer a range of research questions. These in vitro models are grown on permeable two-chamber systems; however, commercially available, polymer-based cell culture inserts are around 10 μm thick. Since the basement membrane found in biological systems is usually less than 1 μm thick, the 10-fold thickness of cell culture inserts is a major limitation in the establishment of realistic models. In this work, an alternative insert, accommodating an ultrathin ceramic membrane with a thickness of only 500 nm (i.e., the Silicon nitride Microporous Permeable Insert [SIMPLI]-well), was produced and used to refine an established human alveolar barrier coculture model by both replacing the conventional inserts with the SIMPLI-well and completing it with endothelial cells. The structural–functional relationship of the model was evaluated, including the translocation of gold nanoparticles across the barrier, revealing a higher translocation if compared to corresponding polyethylene terephthalate (PET) membranes. This study demonstrates the power of the SIMPLI-well system as a scaffold for epithelial tissue cell models on a truly biomimetic scale, allowing construction of more functionally accurate models of human biological barriers. more...
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- 2015
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17. Form Follows Function: Nanoparticle Shape and Its Implications for Nanomedicine
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Alke Petri-Fink, Calum Kinnear, Barbara Rothen-Rutishauser, Thomas Moore, and Laura Rodriguez-Lorenzo
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Chemistry ,Polymers ,Nanoparticle ,Metal Nanoparticles ,Nanotechnology ,02 engineering and technology ,General Chemistry ,Models, Theoretical ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Endocytosis ,0104 chemical sciences ,Nanomedicine ,Lung disease ,Nanoparticles ,Graphite ,0210 nano-technology - Abstract
This review is a comprehensive description of the past decade of research into understanding how the geometry and size of nanoparticles affect their interaction with biological systems: from single cells to whole organisms. Recently, there has been a great deal of effort to use both the shape and the size of nanoparticles to target specific cellular uptake mechanisms, biodistribution patterns, and pharmacokinetics. While the successes of spherical lipid-based nanoparticles have heralded marked changes in chemotherapy worldwide, the history of asbestos-induced lung disease casts a long shadow over fibrous materials to date. The impact of particle morphology is known to be intertwined with many physicochemical parameters, namely, size, elasticity, surface chemistry, and biopersistence. In this review, we first highlight some of the morphologies observed in nature as well as shapes available to us through synthetic strategies. Following this we discuss attempts to understand the cellular uptake of nanoparticles through various theoretical models before comparing this with observations from in vitro and in vivo experiments. In addition, we consider the impact of nanoparticle shape at different size regimes on targeting, cytotoxicity, and cellular mechanics. more...
- Published
- 2017
18. Polyvinylalkohol als biokompatibles Polymer zur Passivierung von Goldnanostäbchen
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Calum Kinnear, Andreas F. M. Kilbinger, David Burnand, Alke Petri-Fink, Barbara Rothen-Rutishauser, and Martin J. D. Clift
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General Medicine - Abstract
Die Oberflachenfunktionalisierung von Goldnanostabchen mit Polymeren ist aufgrund der daraus resultierenden kolloidalen Stabilitat und der Biovertraglichkeit der Nanopartikel von groser Bedeutung. Die normalerweise vorhandene toxische Doppelschicht aus dem kationische Tensid Cetyltrimethylammoniumbromid (CTAB), das an die Oberflache der Nanostabchen adsorbiert ist, erschwert diesen Prozess jedoch erheblich. Nachstehend erlautern wir eine Strategie zur biokompatiblen Funktionalisierung der Nanostabchen mit hydrophoben Polymervorlaufern, hier Polyvinylacetat, die anschliesend in ihr hydrophiles Gegenstuck, Polyvinylalkohol, uberfuhrt werden. Dieses Polymer wurde aufgrund seiner hohen Biovertraglichkeit, den veranderbaren hydrophilen und hydrophoben Eigenschaften und dem hohem Funktionalisierungsgrad gewahlt. Die Vertraglichkeit der oberflachenfunktionalisierten Goldnanostabchen wurde an primaren Makrophagen, die aus Monozyten differenziert wurden, getestet; die Vorteile der veranderlichen hydrophoben Eigenschaften wurden durch die langfristig stabile Einkapselung eines hydrophoben Beispielmedikaments gezeigt. more...
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- 2014
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19. Gold Nanorods: Controlling Their Surface Chemistry and Complete Detoxification by a Two-Step Place Exchange
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Carola Endes, Calum Kinnear, Martin J. D. Clift, Alke Petri-Fink, Barbara Rothen-Rutishauser, and Hervé Dietsch
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Nanotubes ,Surface Properties ,Tumor Necrosis Factor-alpha ,Chemistry ,Macrophages ,Two step ,Nanoparticle ,Nanotechnology ,General Medicine ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Catalysis ,Polyethylene Glycols ,0104 chemical sciences ,Quaternary Ammonium Compounds ,Colloid ,Chemical engineering ,Detoxification ,Humans ,Nanorod ,Gold ,0210 nano-technology - Abstract
Surface functionalization: Complete detoxification of gold nanorods was achieved by manipulating the position in the stability map between surface-adsorbing polyethylene glycol ({PEG}) and destabilizing ethanol. This robust procedure complements studies related to the effects of shape when contemplating the nanoparticle-cell interaction. more...
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- 2013
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20. High-content analysis of factors affecting gold nanoparticle uptake by neuronal and microglial cells in culture
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Meike Mevissen, Anja-Maria Möller, Calum Kinnear, Michael Hubert Stoffel, Kathrin Kuehni-Boghenbor, Gertraud Schüpbach, Ana Stojiljkovic, and Véronique Gaschen
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0301 basic medicine ,Cell type ,Materials science ,Silver ,media_common.quotation_subject ,Metal Nanoparticles ,610 Medicine & health ,Apoptosis ,02 engineering and technology ,Cell Line ,03 medical and health sciences ,Mice ,Cytotoxic T cell ,Animals ,Humans ,General Materials Science ,Bovine serum albumin ,Particle Size ,Internalization ,media_common ,Neurons ,biology ,021001 nanoscience & nanotechnology ,Fetuin ,Wheat germ agglutinin ,030104 developmental biology ,Colloidal gold ,High-content screening ,Immunology ,Biophysics ,biology.protein ,570 Life sciences ,Gold ,Microglia ,0210 nano-technology - Abstract
Owing to their ubiquitous distribution, expected beneficial effects and suspected adverse effects, nanoparticles are viewed as a double-edged sword, necessitating a better understanding of their interactions with tissues and organisms. Thus, the goals of the present study were to develop and present a method to generate quantitative data on nanoparticle entry into cells in culture and to exemplarily demonstrate the usefulness of this approach by analyzing the impact of size, charge and various proteinaceous coatings on particle internalization. N9 microglial cells and both undifferentiated and differentiated SH-SY5Y neuroblastoma cells were exposed to customized gold nanoparticles. After silver enhancement, the particles were visualized by epipolarization microscopy and analysed by high-content analysis. The value of this approach was substantiated by assessing the impact of various parameters on nanoparticle uptake. Uptake was higher in microglial cells than in neuronal cells. Only microglial cells showed a distinct size preference, preferring particles with a diameter of 80 nm. Positive surface charge had the greatest impact on particle uptake. Coating with bovine serum albumin, fetuin or protein G significantly increased particle internalization in microglial cells but not in neuronal cells. Coating with wheat germ agglutinin increased particle uptake in both N9 and differentiated SH-SY5Y cells but not in undifferentiated SH-SY5Y cells. Furthermore, internalization was shown to be an active process and indicators of caspase-dependent apoptosis revealed that gold nanoparticles did not have any cytotoxic effects. The present study thus demonstrates the suitability of gold nanoparticles and high-content analysis for assessing numerous variables in a stringently quantitative and statistically significant manner. Furthermore, the results presented herein showcase the feasibility of specifically targeting nanoparticles to distinct cell types. more...
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- 2016
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21. A new angle on dynamic depolarized light scattering: number-averaged size distribution of nanoparticles in focus
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Calum Kinnear, Alke Petri-Fink, Laura Rodriguez-Lorenzo, Christoph Geers, Sandor Balog, and Dominic A. Urban
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Aqueous solution ,Materials science ,business.industry ,Dispersity ,Nanoparticle ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Light scattering ,0104 chemical sciences ,Optics ,Dynamic light scattering ,Chemical physics ,Surface modification ,General Materials Science ,0210 nano-technology ,business ,Anisotropy ,Focus (optics) - Abstract
Size polydispersity is a common phenomenon that strongly influences the physicochemical properties of nanoparticles (NPs). We present an analytical approach that is universally applicable to characterizing optically anisotropic round NPs and determines directly the number-averaged size distribution and polydispersity via depolarized dynamic light scattering (DDLS). To demonstrate, we use aqueous suspensions of Au NPs of different sizes and surface functionalization. more...
- Published
- 2016
22. Protein Coronas: Beyond Global Charge: Role of Amine Bulkiness and Protein Fingerprint on Nanoparticle-Cell Interaction (Small 46/2018)
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Calum Kinnear, Miguel Spuch-Calvar, David Burnand, Thomas Moore, Sandor Balog, Barbara Rothen-Rutishauser, Jörn Dengjel, Ana Milosevic, and Alke Petri-Fink
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Biomaterials ,Chemistry ,Fingerprint (computing) ,Nanoparticle ,General Materials Science ,Charge (physics) ,Amine gas treating ,General Chemistry ,Surface charge ,Photochemistry ,Biotechnology - Published
- 2018
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23. Decoupling the shape parameter to assess gold nanorod uptake by mammalian cells
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Laura Rodriguez-Lorenzo, Sara Bals, Calum Kinnear, Bart Goris, Martin J. D. Clift, Alke Petri-Fink, and Barbara Rothen-Rutishauser
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Materials science ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,Endocytosis ,01 natural sciences ,Exocytosis ,Mice ,Animals ,Humans ,General Materials Science ,Particle Size ,Nanotubes ,Physics ,Rational design ,Receptor-mediated endocytosis ,021001 nanoscience & nanotechnology ,In vitro ,0104 chemical sciences ,Cancer cell ,Biophysics ,Nanomedicine ,Nanoparticles ,Nanorod ,Gold ,0210 nano-technology ,HeLa Cells - Abstract
The impact of nanoparticles (NPs) upon biological systems can be fundamentally associated with their physicochemical parameters. A further often-stated tenet is the importance of NP shape on rates of endocytosis. However, given the convoluted parameters concerning the NP–cell interaction, it is experimentally challenging to attribute any findings to shape alone. Herein we demonstrate that shape, below a certain limit, which is specific to nanomedicine, is not important for the endocytosis of spherocylinders by either epithelial or macrophage cells in vitro. Through a systematic approach, we reshaped a single batch of gold nanorods into different aspect ratios resulting in near-spheres and studied their cytotoxicity, (pro-)inflammatory status, and endocytosis/exocytosis. It was found that on a length scale of ∼10–90 nm and at aspect ratios less than 5, NP shape has little impact upon their entry into either macrophages or epithelial cells. Conversely, nanorods with an aspect ratio above 5 were preferentially endocytosed by epithelial cells, whereas there was a lack of shape dependent uptake following exposure to macrophages in vitro. These findings have implications both in the understanding of nanoparticle reshaping mechanisms, as well as in the future rational design of nanomaterials for biomedical applications. more...
- Published
- 2016
24. Plasmonic nanoparticles and their characterization in physiological fluids
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Sandor Balog, Dominic Urban, Barbara Rothen-Rutishauser, Alke Fink, Calum Kinnear, and Laura Rodriguez-Lorenzo
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Plasmonic nanoparticles ,Chemistry ,Nanoparticle ,Nanotechnology ,02 engineering and technology ,Surfaces and Interfaces ,General Medicine ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Characterization (materials science) ,Body Fluids ,Human health ,Colloid and Surface Chemistry ,Microscopy, Electron, Transmission ,Particle ,Humans ,Nanoparticles ,Physical and Theoretical Chemistry ,Physiological fluid ,0210 nano-technology ,Biotechnology - Abstract
Nanoparticles possess unique properties beyond that of classical materials, and while these properties can be used for designing a dedicated functionality, they may also pose a problem to living organisms, to human health and the environment. The specific primary routes by which nanoparticles may interact with the human body include inhalation, injection, ingestion and application to the skin. Independent of the entry route, the particles inevitably encounter a complex physiological fluid populated with e.g. proteins, vitamins, lipids and salts/ions. Different consequences of such an encounter may include formation of a surface-bound protein layer, particle dissolution or aggregation, which are expected to have a crucial impact on cellular interaction. Understanding cellular responses to nanoparticle interactions starts with understanding particle behavior in physiological fluids. Nanoparticles are now available in practically any size, shape and functionalization, to promote distinct optical, magnetic, and physico-chemical properties, making the prediction of their behavior, in physiological fluids, not a trivial task. Characterization has therefore become of paramount importance. In this review, we give an overview about the diversity of physiological fluids as well as present an inventory of the most relevant experimental techniques used to study plasmonic nanoparticles. more...
- Published
- 2015
25. Fate of cellulose nanocrystal aerosols deposited on the lung cell surface in vitro
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Alke Petri-Fink, Calum Kinnear, Carola Endes, E. Johan Foster, Martin J. D. Clift, Silvana Mueller, Christoph Weder, Barbara Rothen-Rutishauser, and Dimitri Vanhecke
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Polymers and Plastics ,Cell ,Nanofibers ,Nanoparticle ,Bioengineering ,Nanotechnology ,02 engineering and technology ,Respiratory Mucosa ,010402 general chemistry ,01 natural sciences ,Cell Line ,Biomaterials ,chemistry.chemical_compound ,Materials Chemistry ,medicine ,Humans ,Cellulose ,Lung ,Aerosols ,Inhalation ,021001 nanoscience & nanotechnology ,In vitro ,0104 chemical sciences ,Aerosol ,medicine.anatomical_structure ,chemistry ,Nanocrystal ,Nanofiber ,Biophysics ,Nanoparticles ,0210 nano-technology - Abstract
When considering the inhalation of high-aspect ratio nanoparticles (HARN), the characterization of their specific interaction with lung cells is of fundamental importance to help categorize their potential hazard. The aim of the present study was to assess the interaction of cellulose nanocrystals (CNCs) with a multicellular in vitro model of the epithelial airway barrier following realistic aerosol exposure. Rhodamine-labeled CNCs isolated from cotton (c-CNCs, 237 ± 118 × 29 ± 13 nm) and tunicate (t-CNCs, 2244 ± 1687 × 30 ± 8 nm) were found to display different uptake behaviors due to their length, although also dependent upon the applied concentration, when visualized by laser scanning microscopy. Interestingly, the longer t-CNCs were found to exhibit a lower clearance by the lung cell model compared to the shorter c-CNCs. This difference can be attributed to stronger fiber-fiber interactions between the t-CNCs. In conclusion, nanofiber length and concentration has a significant influence on their interaction with lung cells in vitro. more...
- Published
- 2015
26. Polyvinyl alcohol as a biocompatible alternative for the passivation of gold nanorods
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David Burnand, Andreas F. M. Kilbinger, Alke Petri-Fink, Calum Kinnear, Martin J. D. Clift, and Barbara Rothen-Rutishauser
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Materials science ,Biocompatibility ,Nanoparticle ,Biocompatible Materials ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Polyvinyl alcohol ,Catalysis ,chemistry.chemical_compound ,Pulmonary surfactant ,Humans ,Cells, Cultured ,chemistry.chemical_classification ,Nanotubes ,Polyvinyl acetate ,Cetrimonium ,Macrophages ,General Chemistry ,Polymer ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,chemistry ,Polyvinyl Alcohol ,Cetrimonium Compounds ,Surface modification ,Nanorod ,Gold ,0210 nano-technology - Abstract
The functionalization of gold nanorods (GNRs) with polymers is essential for both their colloidal stability and biocompatibility. However, a bilayer of the toxic cationic surfactant cetyl trimethylammonium bromide (CTAB) adsorbed on the nanorods complicates this process. Herein, we report on a strategy for the biocompatible functionalization of GNRs with a hydrophobic polymeric precursor, polyvinyl acetate, which is then transformed into its hydrophilic analogue, polyvinyl alcohol. This polymer was chosen due to its well-established biocompatibility, tunable "stealth" properties, tunable hydrophobicity, and high degree of functionality. The biocompatibility of the functionalized GNRs was tested by exposing them to primary human blood monocyte derived macrophages; the advantages of tunable hydrophobicity were demonstrated with the long-term stable encapsulation of a model hydrophobic drug molecule. more...
- Published
- 2015
27. Thermally reversible self-assembly of nanoparticles via polymer crystallization
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Sandor Balog, Barbara Rothen-Rutishauser, Alke Fink, and Calum Kinnear
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Materials science ,Polymers and Plastics ,Polymers ,Crystallization of polymers ,Nanoparticle ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,law.invention ,Upper critical solution temperature ,law ,Materials Chemistry ,Crystallization ,Self-assembly of nanoparticles ,chemistry.chemical_classification ,Organic Chemistry ,Polymer ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Chemical engineering ,chemistry ,Colloidal gold ,Nanoparticles ,Self-assembly ,0210 nano-technology - Abstract
The directed self assembly of gold nanoparticles through the crystallization of surface grafted polyethylene oxide ({PEO}) in ethanol–water mixtures is described. This process is fully reversible and tunable through either the size of the core or the polymeric coating. Characterization by X ray scattering and electron microscopy of the self assembled structures reveals order at the nanoscale typically not the case for thermoresponsive gold nanoparticles coated with lower or upper critical solution temperature polymers. A further novelty is the result of selective binding of calcium ions to the {PEO} in the fluid state: a reversible thermoresponsive transition become irreversible. more...
- Published
- 2014
28. An in vitro testing strategy towards mimicking the inhalation of high aspect ratio nanoparticles
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Sandra Camarero-Espinosa, Carola Endes, Martin J. D. Clift, Dimitri Vanhecke, Silvana Mueller, Christoph Weder, Calum Kinnear, Otmar Schmid, Barbara Rothen-Rutishauser, Alke Petri-Fink, and E. Johan Foster more...
- Subjects
Air Liquid Interface ,Alternative Testing Strategies ,Cellulose Nanocrystals ,Characterisation ,High Aspect Ratio Nanoparticles ,In Vitro ,Inhalation ,Time Factors ,Materials science ,Cell Survival ,Health, Toxicology and Mutagenesis ,Nanofibers ,Alternative testing strategies ,Nanoparticle ,Nanotechnology ,Respiratory Mucosa ,Toxicology ,Risk Assessment ,In vitro ,Cell Line, Tumor ,Toxicity Tests ,Humans ,Cellulose ,Cytotoxicity ,Aerosols ,Inhalation exposure ,Inhalation Exposure ,Chromatography ,Dose-Response Relationship, Drug ,Research ,High aspect ratio nanoparticles ,Macrophages ,Nebulizers and Vaporizers ,Cellulose nanocrystals ,Dendritic Cells ,Quartz ,General Medicine ,Quartz Crystal Microbalance Techniques ,Quartz crystal microbalance ,Coculture Techniques ,Oxidative Stress ,Nanofiber ,Nanoparticles ,Air liquid interface ,Asbestos, Amosite ,Inflammation Mediators - Abstract
Background The challenge remains to reliably mimic human exposure to high aspect ratio nanoparticles (HARN) via inhalation. Sophisticated, multi-cellular in vitro models are a particular advantageous solution to this issue, especially when considering the need to provide realistic and efficient alternatives to invasive animal experimentation for HARN hazard assessment. By incorporating a systematic test-bed of material characterisation techniques, a specific air-liquid cell exposure system with real-time monitoring of the cell-delivered HARN dose in addition to key biochemical endpoints, here we demonstrate a successful approach towards investigation of the hazard of HARN aerosols in vitro. Methods Cellulose nanocrystals (CNCs) derived from cotton and tunicates, with differing aspect ratios (~9 and ~80), were employed as model HARN samples. Specifically, well-dispersed and characterised CNC suspensions were aerosolised using an “Air Liquid Interface Cell Exposure System” (ALICE) at realistic, cell-delivered concentrations ranging from 0.14 to 1.57 μg/cm2. The biological impact (cytotoxicity, oxidative stress levels and pro-inflammatory effects) of each HARN sample was then assessed using a 3D multi-cellular in vitro model of the human epithelial airway barrier at the air liquid interface (ALI) 24 hours post-exposure. Additionally, the testing strategy was validated using both crystalline quartz (DQ12) as a positive particulate control in the ALICE system and long fibre amosite asbestos (LFA) to confirm the susceptibility of the in vitro model to a fibrous insult. Results A rapid (≤4 min), controlled nebulisation of CNC suspensions enabled a dose-controlled and spatially homogeneous CNC deposition onto cells cultured under ALI conditions. Real-time monitoring of the cell-delivered CNC dose with a quartz crystal microbalance was accomplished. Independent of CNC aspect ratio, no significant cytotoxicity (p > 0.05), induction of oxidative stress, or (pro)-inflammatory responses were observed up to the highest concentration of 1.57 μg/cm2. Both DQ12 and LFA elicited a significant (p more...
- Published
- 2014
- Full Text
- View/download PDF
29. In vitro dosimetry of agglomerates
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Vera Hirsch, Sandor Balog, Barbara Rothen-Rutishauser, Christophe Monnier, Alke Fink, Calum Kinnear, and Laura Rodriguez-Lorenzo
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Materials science ,Light ,Economies of agglomeration ,Cell Survival ,Tiopronin ,In vitro exposure ,Nanoparticle ,Metal Nanoparticles ,Nanotechnology ,02 engineering and technology ,Hydrogen-Ion Concentration ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Agglomerate ,Polyvinyl Alcohol ,Biological fluids ,Dosimetry ,Humans ,Scattering, Radiation ,General Materials Science ,Gold ,0210 nano-technology ,HeLa Cells - Abstract
Agglomeration of nanoparticles in biological fluids is a pervasive phenomenon that leads to difficulty in the interpretation of results from in vitro exposure, primarily due to differing particokinetics of agglomerates to nanoparticles. Therefore, well-defined small agglomerates were designed that possessed different particokinetic profiles, and their cellular uptake was compared to a computational model of dosimetry. The approach used here paves the way for a better understanding of the impact of agglomeration on the nanoparticle–cell interaction. more...
- Published
- 2014
30. Surface charge of polymer coated SPIONs influences the serum protein adsorption, colloidal stability and subsequent cell interaction in vitro
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Calum Kinnear, Alke Fink, Barbara Rothen-Rutishauser, Marc Moniatte, Vera Hirsch, and Martin J. D. Clift
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Materials science ,Light ,Polymers ,Surface Properties ,Metal Nanoparticles ,Nanoparticle ,02 engineering and technology ,010402 general chemistry ,Ferric Compounds ,01 natural sciences ,Viscosity ,Colloid ,Adsorption ,Chlorides ,Humans ,Scattering, Radiation ,General Materials Science ,Colloids ,Surface charge ,chemistry.chemical_classification ,Chromatography ,Blood Proteins ,Polymer ,021001 nanoscience & nanotechnology ,Charged particle ,In vitro ,0104 chemical sciences ,chemistry ,Polyvinyl Alcohol ,Biophysics ,0210 nano-technology ,HeLa Cells - Abstract
It is known that the nanoparticle-cell interaction strongly depends on the physicochemical properties of the investigated particles. In addition, medium density and viscosity influence the colloidal behaviour of nanoparticles. Here, we show how nanoparticle-protein interactions are related to the particular physicochemical characteristics of the particles, such as their colloidal stability, and how this significantly influences the subsequent nanoparticle-cell interaction in vitro. Therefore, different surface charged superparamagnetic iron oxide nanoparticles were synthesized and characterized. Similar adsorbed protein profiles were identified following incubation in supplemented cell culture media, although cellular uptake varied significantly between the different particles. However, positively charged nanoparticles displayed a significantly lower colloidal stability than neutral and negatively charged particles while showing higher non-sedimentation driven cell-internalization in vitro without any significant cytotoxic effects. The results of this study strongly indicate therefore that an understanding of the aggregation state of NPs in biological fluids is crucial in regards to their biological interaction(s). more...
- Published
- 2013
- Full Text
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31. Fate of Cellulose Nanocrystal Aerosols Deposited onthe Lung Cell Surface In Vitro.
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Carola Endes, Silvana Mueller, Calum Kinnear, Dimitri Vanhecke, E. Johan Foster, Alke Petri-Fink, Christoph Weder, MartinJ. D. Clift, and Barbara Rothen-Rutishauser
- Published
- 2015
- Full Text
- View/download PDF
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