21 results on '"Rose Rosenberg"'
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2. Two Types of Liquid Phase Separation Induced by Soft Centrifugation in Aqueous Ethyl Acetate Using Ethanol as Cosolvent
- Author
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Helmut Cölfen, Rose Rosenberg, Dirk Haffke, Simon Stemplinger, Thomas Zemb, and Dominik Horinek
- Subjects
Science - Abstract
Water/ethyl acetate/ethanol is widely used as a “green” extractant system. We show that 2 different types of phase separation can be induced upon centrifugation in this ternary system using ethanol as a cosolvent of water and ethyl acetate: centrifuge-induced criticality and centrifuge-induced emulsification. The expected composition profiles of samples after centrifugation can be represented by bent lines in a ternary phase diagram when gravitational energy is added to the free energy of mixing. The experimental equilibrium composition profiles behave qualitatively as expected and can be predicted using a phenomenological theory of mixing. The concentration gradients are small except near the critical point, as expected for small molecules. Nevertheless, they are usable when accompanied by temperature cycles. These findings open new possibilities of centrifugal separation, even if control is delicate during temperature cycles. These schemes are accessible even at relatively low centrifugation speed for molecules that float and sediment with apparent molar masses several hundred times larger than the molecular mass.
- Published
- 2023
- Full Text
- View/download PDF
3. Growth of organic crystals via attachment and transformation of nanoscopic precursors
- Author
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Yuan Jiang, Matthias Kellermeier, Denis Gebauer, Zihao Lu, Rose Rosenberg, Adrian Moise, Michael Przybylski, and Helmut Cölfen
- Subjects
Science - Abstract
Multistage crystallization pathways involving nanoscopic precursors or intermediates have been proposed for various systems. Here, the authors find compelling evidence that nanoscopic species participate in the crystallization of glutamic acid monohydrate, extending this non-classical growth mechanism to organic crystals.
- Published
- 2017
- Full Text
- View/download PDF
4. Simple Determination of Gold Nanocrystal Dimensions by Analytical Ultracentrifugation via Surface Ligand-Solvent Density Matching
- Author
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Guillermo González-Rubio, Holger Hilbert, Rose Rosenberg, Bing Ni, Lisa Fuhrer, and Helmut Cölfen
- Subjects
analytical ultracentrifugation ,size distribution ,surface ligand ,gold nanocrystals ,density matching ,Chemistry ,QD1-999 - Abstract
Analytical ultracentrifugation (AUC) is a powerful technique to observe colloidal nanocrystals (NCs) directly in solution and obtain critical information about their physical-chemical properties. Nevertheless, a more comprehensive implementation of AUC for the characterisation of such a class of crystalline colloids has been traditionally impaired by the requirement of having a priori knowledge of the complex, multilayered structure formed by NC in solution. This includes the nature (density and mass) of the surface ligands (SLs) that provide NC colloidal stability and the shell of solvent molecules formed on it. Herein, we propose a methodology to determine the NCs size by using SLs with a density equal to that of the solvent. Thereby, the buoyancy force of the SL shell is neutral, and the density of the NCs is sufficient a priori knowledge to calculate their related mass and size distributions. The simplicity and reliability of the method are evaluated with cetyltrimethylammonium bromide (CTAB) stabilized spherical gold NCs (AuNCs) of dimensions ranging from 1 to 17 nm. The proposed method has great potential to be transferred to any non-crystalline and crystalline colloids of different nature and composition, which have a density that is equal to the bulk and can be stabilized by SLs having a density that matches that of the solvent.
- Published
- 2021
- Full Text
- View/download PDF
5. A multilaboratory comparison of calibration accuracy and the performance of external references in analytical ultracentrifugation.
- Author
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Huaying Zhao, Rodolfo Ghirlando, Carlos Alfonso, Fumio Arisaka, Ilan Attali, David L Bain, Marina M Bakhtina, Donald F Becker, Gregory J Bedwell, Ahmet Bekdemir, Tabot M D Besong, Catherine Birck, Chad A Brautigam, William Brennerman, Olwyn Byron, Agnieszka Bzowska, Jonathan B Chaires, Catherine T Chaton, Helmut Cölfen, Keith D Connaghan, Kimberly A Crowley, Ute Curth, Tina Daviter, William L Dean, Ana I Díez, Christine Ebel, Debra M Eckert, Leslie E Eisele, Edward Eisenstein, Patrick England, Carlos Escalante, Jeffrey A Fagan, Robert Fairman, Ron M Finn, Wolfgang Fischle, José García de la Torre, Jayesh Gor, Henning Gustafsson, Damien Hall, Stephen E Harding, José G Hernández Cifre, Andrew B Herr, Elizabeth E Howell, Richard S Isaac, Shu-Chuan Jao, Davis Jose, Soon-Jong Kim, Bashkim Kokona, Jack A Kornblatt, Dalibor Kosek, Elena Krayukhina, Daniel Krzizike, Eric A Kusznir, Hyewon Kwon, Adam Larson, Thomas M Laue, Aline Le Roy, Andrew P Leech, Hauke Lilie, Karolin Luger, Juan R Luque-Ortega, Jia Ma, Carrie A May, Ernest L Maynard, Anna Modrak-Wojcik, Yee-Foong Mok, Norbert Mücke, Luitgard Nagel-Steger, Geeta J Narlikar, Masanori Noda, Amanda Nourse, Tomas Obsil, Chad K Park, Jin-Ku Park, Peter D Pawelek, Erby E Perdue, Stephen J Perkins, Matthew A Perugini, Craig L Peterson, Martin G Peverelli, Grzegorz Piszczek, Gali Prag, Peter E Prevelige, Bertrand D E Raynal, Lenka Rezabkova, Klaus Richter, Alison E Ringel, Rose Rosenberg, Arthur J Rowe, Arne C Rufer, David J Scott, Javier G Seravalli, Alexandra S Solovyova, Renjie Song, David Staunton, Caitlin Stoddard, Katherine Stott, Holger M Strauss, Werner W Streicher, John P Sumida, Sarah G Swygert, Roman H Szczepanowski, Ingrid Tessmer, Ronald T Toth, Ashutosh Tripathy, Susumu Uchiyama, Stephan F W Uebel, Satoru Unzai, Anna Vitlin Gruber, Peter H von Hippel, Christine Wandrey, Szu-Huan Wang, Steven E Weitzel, Beata Wielgus-Kutrowska, Cynthia Wolberger, Martin Wolff, Edward Wright, Yu-Sung Wu, Jacinta M Wubben, and Peter Schuck
- Subjects
Medicine ,Science - Abstract
Analytical ultracentrifugation (AUC) is a first principles based method to determine absolute sedimentation coefficients and buoyant molar masses of macromolecules and their complexes, reporting on their size and shape in free solution. The purpose of this multi-laboratory study was to establish the precision and accuracy of basic data dimensions in AUC and validate previously proposed calibration techniques. Three kits of AUC cell assemblies containing radial and temperature calibration tools and a bovine serum albumin (BSA) reference sample were shared among 67 laboratories, generating 129 comprehensive data sets. These allowed for an assessment of many parameters of instrument performance, including accuracy of the reported scan time after the start of centrifugation, the accuracy of the temperature calibration, and the accuracy of the radial magnification. The range of sedimentation coefficients obtained for BSA monomer in different instruments and using different optical systems was from 3.655 S to 4.949 S, with a mean and standard deviation of (4.304 ± 0.188) S (4.4%). After the combined application of correction factors derived from the external calibration references for elapsed time, scan velocity, temperature, and radial magnification, the range of s-values was reduced 7-fold with a mean of 4.325 S and a 6-fold reduced standard deviation of ± 0.030 S (0.7%). In addition, the large data set provided an opportunity to determine the instrument-to-instrument variation of the absolute radial positions reported in the scan files, the precision of photometric or refractometric signal magnitudes, and the precision of the calculated apparent molar mass of BSA monomer and the fraction of BSA dimers. These results highlight the necessity and effectiveness of independent calibration of basic AUC data dimensions for reliable quantitative studies.
- Published
- 2015
- Full Text
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6. Erratum: Growth of organic crystals via attachment and transformation of nanoscopic precursors
- Author
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Yuan Jiang, Matthias Kellermeier, Denis Gebauer, Zihao Lu, Rose Rosenberg, Adrian Moise, Michael Przybylski, and Helmut Cölfen
- Subjects
Science - Abstract
Nature Communications 8: Article number: 15933 (2017); Published 21 June 2017; Updated 17 July 2017 The original version of this Article contained an error in the spelling of the author Denis Gebauer, which was incorrectly given as Denis Gebaue. This has now been corrected in both the PDF and HTML versions of the Article.
- Published
- 2017
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7. Analysis of Magic-Size Clusters in Crude Reaction Mixtures Using Multiwavelength Analytical Ultracentrifugation
- Author
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Eva Peters, Rose Rosenberg, Helmut Cölfen, and Klaus Boldt
- Subjects
General Energy ,Physical and Theoretical Chemistry ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials - Published
- 2022
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8. Two Types of Liquid Phase Separation Induced by Soft Centrifugation in Aqueous Ethyl Acetate Using Ethanol as Cosolvent
- Author
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Helmut Coelfen, Rose Rosenberg, Dirk Haffke, Simon Stemplinger, Thomas Zemb, and Dominik Horinek
- Subjects
Multidisciplinary ,540 Chemie ,ddc:540 - Abstract
Water-ethyl acetate-ethanol is widely used as “green” extractant system. We show that two different types of phase separation can be induced upon centrifugation in this ternary system using ethanol as a co-solvent of water and ethyl acetate (EA): centrifuge-induced criticality and centrifuge-induced emulsification. The expected composition profiles of samples after centrifugation can be represented by bent lines in a ternary phase diagram when gravitational energy is added to the free energy of mixing. The experimental equilibrium composition profiles behave qualitatively as expected and can be predicted using a phenomenological theory of mixing. The concentration gradients are small except near the critical point, as expected for small molecules. Nevertheless, they are usable when accompanied by temperature cycles. These findings open new possibilities of centrifugal separation, even if control is delicate during temperature cycles. These schemes are accessible even at relatively low centrifugation speed for molecules that float and sediment with apparent molar masses several hundred times larger than the molecular mass.
- Published
- 2023
9. New Insights into the Nucleation of Portlandite and the Effects of Polymeric Additives
- Author
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Benjamin Madeja, Denis Gebauer, Maximilian Marsiske, Andreas Ott, Markus Rückel, Rose Rosenberg, Annet Baken, Tomasz M. Stawski, Alejandro Fernandez-Martinez, Alexander E. S. Van Driessche, Helmut Cölfen, and Matthias Kellermeier
- Published
- 2023
- Full Text
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10. Phase separation of binary mixtures induced by soft centrifugal fields
- Author
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Rose Rosenberg, Stjepan Marčelja, Thomas Zemb, Helmut Cölfen, Werner Kunz, Jean-François Dufrêche, Dominik Horinek, Dirk Haffke, Tri ionique par les Systèmes Moléculaires auto-assemblés (LTSM), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), University of Konstanz, Australian National University (ANU), Modélisation Mésoscopique et Chimie Théorique (LMCT), University of Regensburg, European Project: 320915,EC:FP7:ERC,ERC-2012-ADG_20120216,REE-CYCLE(2013), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Phase transition ,Molar mass ,Materials science ,Opacity ,Spinodal decomposition ,General Physics and Astronomy ,Thermodynamics ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry ,Colloid ,Critical opalescence ,Critical point (thermodynamics) ,Sedimentation equilibrium ,ddc:540 ,Physical and Theoretical Chemistry ,0210 nano-technology - Abstract
International audience; We use the model system ethanol–dodecane to demonstrate that giant critical fluctuations induced by easily accessible weak centrifugal fields as low as 2000g can be observed above the miscibility gap of a binary liquid mixture. Moreover, several degrees above the phase transition, i.e. in the one-phase region, strong gradients of ethanol concentration occur upon centrifugation. In this case, the standard interpretation of sedimentation equilibrium in the analytical ultracentrifuge (AUC) yields an apparent molar mass of ethanol three orders of magnitude higher than the real value. Notably, these composition gradients have no influence on the distribution gradient of solutes such as dyes like Nile red. The thick opaque interphase formed upon centrifugation does not appear as the commonly observed sharp meniscus, but as a turbidity zone, similar to critical opalescence. This layer is a few millimeters thick and separates two fluids with low compositional gradients. All these effects can be qualitatively understood and explained using the Flory–Huggins solution model coupled to classical density functional theory (DFT). In this domain hetero-phase fluctuations can be triggered by gravity even far from the critical point. Taking into account Jean Perrin's approach to external fields in colloids, a self-consistent definition of the Flory effective volume and an explicit calculation of the total free energy per unit volume is possible.
- Published
- 2021
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11. Highly Hydrated Paramagnetic Amorphous Calcium Carbonate Nanoclusters as a Superior MRI Contrast Agent
- Author
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Cong Sui, Denis Gebauer, Li-Bo Mao, Fei Li, Hui-Qin Wen, Ya-Dong Wu, Jonathan Avaro, Yun-Jun Xu, Zhao Pan, Xu Yan, Liang Dong, Huai-Ling Gao, Yang Lu, Rose Rosenberg, Shu-Hong Yu, Yang Zhao, and Helmut Coelfen
- Subjects
chemistry.chemical_compound ,Paramagnetism ,Materials science ,chemistry ,MRI contrast agent ,Inorganic chemistry ,Amorphous calcium carbonate ,Nanoclusters - Abstract
Amorphous calcium carbonate (ACC) plays a key role as transient precursor in the early stages of biogenic calcium carbonate formation in nature. However, due to its instability in aqueous solution, there is still rare success to utilize ACC in biomedicine. Here, we report the mutual effect between paramagnetic gadolinium ions and ACC, resulting in ultrafine paramagnetic amorphous carbonate nanoclusters (ACNC) in the presence of both gadolinium occluded highly hydrated ACC-like environment and poly(acrylic acid). Gadolinium is confirmed to enhance the water content in ACC, and the high water content of ACNC (23 molecules H2O per 1 Gd) contributes to the much enhanced magnetic resonance imaging (MRI) contrast efficiency compared with commercially available gadolinium-based contrast agents. Furthermore, the enhanced T1 weighted MRI performance and biocompatibility of ACNC are further evaluated in various animals including rat, rabbit and beagle dog, in combination with promising safety in vivo. Overall, exceptionally facile mass-productive ACNC exhibits superb imaging performance and impressive stability, which provides a promising strategy to design MR contrast agents.
- Published
- 2021
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12. Morphogenesis of Magnetite Mesocrystals: Interplay Between Nanoparticle Morphology and Solvation Shell
- Author
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Julian Brunner, Britta Maier, Sabrina L. J. Thomä, Felizitas Kirner, Igor Baburin, Dmitry Lapkin, Rose Rosenberg, Sebastian Sturm, Dameli Assalauova, Jerome Carnis, Young Yong Kim, Zhe Ren, Fabian Westermeier, Sebastian Theiss, Horst Borrmann, Sebastian Polarz, Alexander Eychmüller, Axel Lubk, Ivan Vartanyants, Helmut Cölfen, Mirijam Zobel, Elena Sturm, and Elena Sturm (née Rosseeva)
- Abstract
In this study, faceted mesocrystals have been assembled from the dispersion of truncated cubic-shaped iron oxide nanoparticles stabilized by oleic acid (OA) molecules using the non-solvent “gas phase diffusion technique” into an organic solvent. The effects of synthesis conditions as well as of the nanoparticle size and shape on the structure and morphogenesis of mesocrystals were examined. The interactions of OA capped iron oxide nanoparticles with solvent molecules were probed by analytical ultracentrifugation and double difference pair distribution function analysis. It was shown that the structure of the organic shell significantly depends on the nature and polarity of solvent molecules.
- Published
- 2021
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13. Morphogenesis of Magnetite Mesocrystals: Interplay Between Nanoparticle Morphology and Solvation Shell
- Author
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Helmut Cölfen, Jerome Carnis, Sebastian Sturm, Julian Schlotheuber né Brunner, Mirijam Zobel, Sebastian Polarz, Rose Rosenberg, Sabrina L. J. Thomä, Britta Maier, Felizitas Kirner, Sebastian Theiss, Dameli Assalauova, Young Yong Kim, Horst Borrmann, Axel Lubk, Fabian Westermeier, Dmitry Lapkin, Alexander Eychmüller, Ivan A. Vartanyants, Zhe Ren, Elena V. Sturm, and Igor A. Baburin
- Subjects
Materials science ,Morphology (linguistics) ,High interest ,General Chemical Engineering ,Nanoparticle ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Solvation shell ,chemistry ,Chemical engineering ,Materials Chemistry ,Self-assembly ,0210 nano-technology ,Magnetite - Abstract
In this study, faceted mesocrystals have been assembled from the dispersion of truncated cubic-shaped iron oxide nanoparticles stabilized by oleic acid (OA) molecules using the non-solvent “gas phase diffusion technique” into an organic solvent. The effects of synthesis conditions as well as of the nanoparticle size and shape on the structure and morphogenesis of mesocrystals were examined. The interactions of OA capped iron oxide nanoparticles with solvent molecules were probed by analytical ultracentrifugation and double difference pair distribution function analysis. It was shown that the structure of the organic shell significantly depends on the nature and polarity of solvent molecules.
- Published
- 2021
- Full Text
- View/download PDF
14. Non-stoichiometric hydrated magnesium-doped calcium carbonate precipitation in ethanol
- Author
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Boaz Pokroy, Helmut Cölfen, Andrea Matteo Maria Condorelli, Giuseppe Falini, Giulia Magnabosco, Denis Gebauer, Rose Rosenberg, Iryna Polishchuk, Magnabosco, Giulia, Condorelli, Andrea M M, Rosenberg, Rose, Polishchuk, Iryna, Pokroy, Boaz, Gebauer, Deni, Cölfen, Helmut, and Falini, Giuseppe
- Subjects
Inorganic chemistry ,chemistry.chemical_element ,010402 general chemistry ,01 natural sciences ,Catalysis ,law.invention ,chemistry.chemical_compound ,law ,Phase (matter) ,Materials Chemistry ,Crystallization ,010405 organic chemistry ,Magnesium ,Precipitation (chemistry) ,Metals and Alloys ,Solvation ,General Chemistry ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Amorphous solid ,Calcium carbonate ,chemistry ,ddc:540 ,calcium carbonate, ethanol, crystallization, magnesium ,Ceramics and Composites ,Stoichiometry - Abstract
The effect of Mg2+ on the precipitation pathway of CaCO3 in absolute ethanol has been studied to investigate the role of ion solvation in the crystallization process. Our data reveal that high concentrations of Mg2+ promote the precipitation of an amorphous transient phase together with non-stoichometric hydrated phases of calcium carbonate. published
- Published
- 2019
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15. Morphogenesis of anisotropic nanoparticles: self-templating via non-classical, fibrillar Cd2Se intermediates
- Author
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Daniel Wurmbrand, Jörg Wolfram Anselm Fischer, Klaus Boldt, and Rose Rosenberg
- Subjects
Materials science ,technology, industry, and agriculture ,Metals and Alloys ,Morphogenesis ,Anisotropic nanoparticles ,02 engineering and technology ,General Chemistry ,Principal factor ,Anisotropic growth ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Catalysis ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,Monomer ,Crystalline semiconductor ,chemistry ,Chemical engineering ,Materials Chemistry ,Ceramics and Composites ,Nanorod ,0210 nano-technology - Abstract
A fibrillar, polymeric intermediate (Cd2Se)n was isolated from the synthesis of CdSe nanorods, which suggests that the reactants themselves can template anisotropic growth. It is shown that high monomer concentration is the principal factor favouring this reaction pathway. The intermediate is distinct from crystalline semiconductor or small clusters and is surprisingly temperature-stable below 250 °C.
- Published
- 2018
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16. Particle Ordering: Order and Defects in Ceramic Semiconductor Nanoparticle Superstructures as a Function of Polydispersity and Aspect Ratio (Part. Part. Syst. Charact. 2/2017)
- Author
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Helmut Cölfen, Tom Kollek, Rose Rosenberg, Melanie Gerigk, Jochen Bahner, Sebastian Polarz, and Stefan Helfrich
- Subjects
Materials science ,Aspect ratio ,Condensed matter physics ,Dispersity ,Nanotechnology ,General Chemistry ,Function (mathematics) ,Condensed Matter Physics ,visual_art ,visual_art.visual_art_medium ,Particle ,General Materials Science ,Ceramic ,Self-assembly ,Semiconductor Nanoparticles - Published
- 2017
- Full Text
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17. Synthesis of calcium carbonate in trace water environments
- Author
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Giulia Magnabosco, Rose Rosenberg, Helmut Cölfen, Boaz Pokroy, Iryna Polishchuk, Giuseppe Falini, Magnabosco, Giulia, Polishchuk, Iryna, Pokroy, Boaz, Rosenberg, Rose, Cölfen, Helmut, and Falini, Giuseppe
- Subjects
FOS: Physical sciences ,Alcohol ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Catalysis ,law.invention ,chemistry.chemical_compound ,law ,Physics - Chemical Physics ,Vaterite ,Materials Chemistry ,Molecule ,Crystallization ,Calcite ,Chemical Physics (physics.chem-ph) ,Condensed Matter - Materials Science ,Precipitation (chemistry) ,Metals and Alloys ,Materials Science (cond-mat.mtrl-sci) ,General Chemistry ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Calcium carbonate ,chemistry ,Chemical engineering ,Calcium carbonate, organic solvent, trace-water environment, high-resolution X-ray powder diffraction, ultracentrifugation ,ddc:540 ,Ceramics and Composites ,Particle ,0210 nano-technology - Abstract
Calcium carbonate (CaCO3) was synthesized from diverse water-free alcohol solutions, resulting in the formation of vaterite and calcite precipitates, or stable particle suspensions, with the dimensions and morphologies depending upon the conditions used. The obtained results shed light on the importance of solvation during crystallization of CaCO3 and open a novel synthetic route for its precipitation in organic solvents. published
- Published
- 2017
18. The Molecular Mechanism of Iron(III) Oxide Nucleation
- Author
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Denis Gebauer, Baohu Wu, Rose Rosenberg, Johanna Scheck, Tomasz M. Stawski, Alexander E. S. Van Driessche, and Markus Drechsler
- Subjects
Chemistry ,Condensation ,Nucleation ,Iron oxide ,Iron(III) oxide ,Nanotechnology ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Chemical basis ,01 natural sciences ,Nanocrystalline material ,0104 chemical sciences ,chemistry.chemical_compound ,Chemical physics ,Molecular mechanism ,General Materials Science ,Nanometre ,Physical and Theoretical Chemistry ,0210 nano-technology - Abstract
A molecular understanding of the formation of solid phases from solution would be beneficial for various scientific fields. However, nucleation pathways are still not fully understood, whereby the case of iron (oxyhydr)oxides poses a prime example. We show that in the prenucleation regime, thermodynamically stable solute species up to a few nanometers in size are observed, which meet the definition of prenucleation clusters. Nucleation then is not governed by a critical size, but rather by the dynamics of the clusters that are forming at the distinct nucleation stages, based on the chemistry of the linkages within the clusters. This resolves a longstanding debate in the field of iron oxide nucleation, and the results may generally apply to oxides forming via hydrolysis and condensation. The (molecular) understanding of the chemical basis of phase separation is paramount for, e.g., tailoring size, shape and structure of novel nanocrystalline materials.
- Published
- 2016
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19. A multilaboratory comparison of calibration accuracy and the performance of external references in analytical ultracentrifugation
- Author
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Tomas Obsil, Helmut Cölfen, Anna Modrak-Wójcik, José García de la Torre, Caitlin I. Stoddard, Ute Curth, Thomas M. Laue, Geeta J. Narlikar, Szu Huan Wang, Carlos Alfonso, Carlos R. Escalante, Jia Ma, Gali Prag, Masanori Noda, Katherine Stott, Klaus Richter, Carrie A. May, Peter Schuck, Fumio Arisaka, Edward Eisenstein, Stephen J. Perkins, Ilan Attali, John P. Sumida, Catherine T. Chaton, Erby E. Perdue, Davis Jose, David Staunton, Matthew A. Perugini, Jin Ku Park, Amanda Nourse, Peter E. Prevelige, Craig L. Peterson, Norbert Mücke, Satoru Unzai, Peter D. Pawelek, Jayesh Gor, Arne C. Rufer, Rose Rosenberg, Hauke Lilie, Martin G. Peverelli, Yee-Foong Mok, Martin Wolff, Jacinta M. Wubben, Luitgard Nagel-Steger, Peter H. von Hippel, Karolin Luger, Edward Wright, Holger M. Strauss, Lenka Rezabkova, Agnieszka Bzowska, Aline Le Roy, Steven E. Weitzel, Jonathan B. Chaires, Elena Krayukhina, Donald F. Becker, Alexandra S. Solovyova, Alison E. Ringel, Chad A. Brautigam, Dalibor Kosek, David J. Scott, Kimberly A. Crowley, Cynthia Wolberger, Soon-Jong Kim, Adam G. Larson, Leslie E. Eisele, Susumu Uchiyama, Gregory J. Bedwell, Javier Seravalli, Bertrand Raynal, Ron M. Finn, Hyewon Kwon, Tabot M. D. Besong, Marina Bakhtina, Ahmet Bekdemir, Shu-Chuan Jao, Bashkim Kokona, Catherine Birck, Roman H. Szczepanowski, Andrew B. Herr, Christine Wandrey, Stephen E. Harding, Daniel D Krzizike, David L. Bain, José G. Hernández Cifre, Grzegorz Piszczek, Renjie Song, Stephan Uebel, Tina Daviter, Damien Hall, Debra M. Eckert, Patrick England, Ingrid Tessmer, Eric Kusznir, Ernest L. Maynard, William L. Dean, Werner Streicher, Christine Ebel, Anna Vitlin Gruber, Beata Wielgus-Kutrowska, Rodolfo Ghirlando, Yu Sung Wu, Ana I. Díez, Olwyn Byron, Robert Fairman, William Brennerman, Henning Gustafsson, Richard Stefan Isaac, Wolfgang Fischle, Elizabeth E. Howell, Ronald T. Toth, Sarah G. Swygert, Ashutosh Tripathy, Arthur J. Rowe, Chad K. Park, Jeffrey A. Fagan, Keith D. Connaghan, Huaying Zhao, Jack A. Kornblatt, Andrew P. Leech, Juan Román Luque-Ortega, BGI Shenzhen, Laboratoire d'Informatique pour l'Entreprise et les Systèmes de Production (LIESP), Université Lumière - Lyon 2 (UL2)-École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Innovative Computing Laboratory [Knoxville] (ICL), The University of Tennessee [Knoxville], Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), EDF R&D (EDF R&D), EDF (EDF), Physikalische Chemie, Universität Konstanz, Photonic Crystal Fibres group, University of Bath [Bath], Institut de biologie structurale (IBS - UMR 5075), Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Biophysique des macromolécules et leurs interactions, Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), Laboratory of Chromatin Biochemistry [Göttingen], Max Planck Institute for Biophysical Chemistry (MPI-BPC), Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, Stellenbosch University, Department of Biochemistry, The Centre for Ornithology, School of Biosciences, College of Life and Environmental Sciences, University of Alabama at Birmingham [ Birmingham] (UAB), Département de Chimie Moléculaire - Chimie Inorganique Redox Biomimétique (DCM - CIRE), Université Joseph Fourier - Grenoble 1 (UJF)-Institut de Chimie Moléculaire de Grenoble (ICMG)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Hormone Research Center, Chonnam National University, Anglophonie : Communautés, Ecritures (ACE ), Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Institut de Chimie des Milieux et Matériaux de Poitiers (IC2MP), Université de Poitiers-Centre National de la Recherche Scientifique (CNRS), Department of Animal Science, Iowa State University (ISU), Université Laval, School of Mathematics [Bristol], University of Bristol [Bristol], Chimie et Biocatalyse, Laboratoire de Physique des Solides (LPS), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Department of marine Ecology, University of Gothenburg (GU), Laboratoire de physique de la matière condensée (LPMC), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Pharma Research Discovery Chemistry, F. Hoffmann-La Roche AG, University of KwaZulu-Natal (UKZN), Institute for Cell and Molecular Biosciences, Newcastle University [Newcastle], Changzhou University, Institut für Geologie und Paläontologie, Westfälische Wilhelms-Universität Münster (WWU), Eindhoven University of Technology [Eindhoven] (TU/e), Department of Biochemistry and Biophysics, UNC Macromolecular Interactions Facility, University of North Carolina [Chapel Hill] (UNC), University of North Carolina System (UNC)-University of North Carolina System (UNC), Institute of Botany, University of Innsbruck, NSF Center for EUV Science and Technology, NSF, Sustainable Energy Economics, Department of mathematics and MOE-LSC, Shanghai Jiao Tong University [Shanghai], Science et Technologie du Lait et de l'Oeuf (STLO), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, Platforms of the Grenoble Instruct centre (ISBG, CNRS-CEA-UJF-EMBL), ANR-10-INBS-0005-02,FRISBI,Infrastructure Française pour la Biologie Structurale Intégrée(2010), ANR-10- LABX-49-01,Labex GRAL,Labex GRAL, Beijing Genomics Institute [Shenzhen] (BGI), Institut National des Sciences Appliquées de Lyon (INSA Lyon), Institut National des Sciences Appliquées (INSA)-Université de Lyon-Institut National des Sciences Appliquées (INSA)-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université Lumière - Lyon 2 (UL2)-École Centrale de Lyon (ECL), Université de Lyon, Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Institut de biologie structurale (IBS - UMR 5075 ), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Département de Chimie Moléculaire (DCM), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Joseph Fourier - Grenoble 1 (UJF), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Poitiers-Institut de Chimie du CNRS (INC), Université Laval [Québec] (ULaval), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), ANR-10-INBS-0005,FRISBI,Infrastructure Française pour la Biologie Structurale Intégrée(2010), ANR-10-LABX-0049,GRAL,Grenoble Alliance for Integrated Structural Cell Biology(2010), Stott, Katherine [0000-0002-4014-1188], Apollo - University of Cambridge Repository, Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Université de Genève = University of Geneva (UNIGE), Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS), Département de Chimie Moléculaire - Chimie Inorganique Redox (DCM - CIRE), Université Joseph Fourier - Grenoble 1 (UJF)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Poitiers-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), F. Hoffmann-La Roche [Basel], University of KwaZulu-Natal [Durban, Afrique du Sud] (UKZN), Westfälische Wilhelms-Universität Münster = University of Münster (WWU), and Leopold Franzens Universität Innsbruck - University of Innsbruck
- Subjects
Accuracy and precision ,Analytical chemistry ,lcsh:Medicine ,Magnification ,02 engineering and technology ,bcs ,Standard deviation ,Analytical Ultracentrifugation ,03 medical and health sciences ,Range (statistics) ,Calibration ,ddc:610 ,lcsh:Science ,030304 developmental biology ,Mathematics ,0303 health sciences ,Field flow fractionation ,Multidisciplinary ,[SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Structural Biology [q-bio.BM] ,lcsh:R ,Reproducibility of Results ,021001 nanoscience & nanotechnology ,3. Good health ,ddc ,Data set ,[SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biomolecules [q-bio.BM] ,ddc:540 ,lcsh:Q ,0210 nano-technology ,Ultracentrifugation ,Research Article - Abstract
30 p.-14 fig. Zhao, Huaying, et alt., Analytical ultracentrifugation (AUC) is a first principles based method to determine absolute sedimentation coefficients and buoyant molar masses of macromolecules and their complexes, reporting on their size and shape in free solution. The purpose of this multi-laboratory study was to establish the precision and accuracy of basic data dimensions in AUC and validate previously proposed calibration techniques. Three kits of AUC cell assemblies containing radial and temperature calibration tools and a bovine serum albumin (BSA) reference sample were shared among 67 laboratories, generating 129 comprehensive data sets. These allowed for an assessment of many parameters of instrument performance, including accuracy of the reported scan time after the start of centrifugation, the accuracy of the temperature calibration, and the accuracy of the radial magnification. The range of sedimentation coefficients obtained for BSA monomer in different instruments and using different optical systems was from 3.655 S to 4.949 S, with a mean and standard deviation of (4.304 ± 0.188) S (4.4%). After the combined application of correction factors derived from the external calibration references for elapsed time, scan velocity, temperature, and radial magnification, the range of s-values was reduced 7-fold with a mean of 4.325 S and a 6-fold reduced standard deviation of ± 0.030 S (0.7%). In addition, the large data set provided an opportunity to determine the instrument-to-instrument variation of the absolute radial positions reported in the scan files, the precision of photometric or refractometric signal magnitudes, and the precision of the calculated apparent molar mass of BSA monomer and the fraction of BSA dimers. These results highlight the necessity and effectiveness of independent calibration of basic AUC data dimensions for reliable quantitative studies.
- Published
- 2015
- Full Text
- View/download PDF
20. Order and Defects in Ceramic Semiconductor Nanoparticle Superstructures as a Function of Polydispersity and Aspect Ratio
- Author
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Rose Rosenberg, Helmut Cölfen, Melanie Gerigk, Jochen Bahner, Sebastian Polarz, Tom Kollek, and Stefan Helfrich
- Subjects
Materials science ,Aspect ratio ,Dispersity ,Nanoparticle ,Nanotechnology ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Amorphous solid ,Chemical physics ,visual_art ,ddc:540 ,visual_art.visual_art_medium ,General Materials Science ,Nanorod ,Ceramic ,Self-assembly ,0210 nano-technology ,Superstructure (condensed matter) - Abstract
The supreme aim of nanoparticle-based materials is to achieve new properties extending over the features of individual constituents. The emergence of cooperativity necessitates precise positioning and orientation of nanoparticle ensembles. Thus, it is important to understand and learn how to control self-assembly processes of nanoparticles. Besides shape, the structural uniformity plays a key role for ordering in superstructures. Therefore, it is challenging to synthesize nanorods with narrow polydispersity. An analysis of the systematic variation of aspect ratio and polydispersity is missing. A series of zinc oxide nanorods is presented and it is shown that their formation resembles step-polymerization with an amorphous precursor state as a monomer and polar ZnO particles as entities capable of growing. The width of nanorods is kept constant (15 nm) and the length is varied between 20 and 100 nm, as well as improving the polydispersity of the nanorod length from 36% to 10%. Best samples have been achieved by post-preparative treatment using gradient centrifugation. A method has been developed for semiquantitative evaluation of orientational order. Ordering in structures formed by quasispherical particles is always low despite low polydispersity. For rod-like nanoparticles with increasing aspect ratio, superstructure order depends on the occurrence of different defects, which correlate differently to nanoparticle polydispersity. published
- Published
- 2016
- Full Text
- View/download PDF
21. Amino acids form prenucleation clusters : ESI-MS as a fast detection method in comparison to analytical ultracentrifugation
- Author
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Michael Przybylski, Ulrike Anders, Rose Rosenberg, Helmut Cölfen, Matthias Kellermeier, and Adrian Moise
- Subjects
Electrospray ,Molecular mass ,Electrospray ionization ,Nucleation ,Analytical chemistry ,Mass spectrometry ,law.invention ,Analytical Ultracentrifugation ,chemistry.chemical_compound ,Monomer ,chemistry ,law ,ddc:540 ,Physical and Theoretical Chemistry ,Crystallization - Abstract
Electrospray ionisation mass spectrometry (ESI-MS) is a fast method which is able to provide molecular mass information with high precision. In this contribution, we show that prenucleation clusters—species recently found to play a pivotal role in crystallisation processes—are detected in addition to monomers by analytical ultracentrifugation (AUC) for the whole range of DL-amino acids, while higher oligomers are simultaneously observed in ESI-MS spectra. This suggests ESI-MS is a fast method to identify systems, which form prenucleation clusters. The occurrence of these clusters as relevant precursors in non-classical nucleation scenarios thus appears to be a more common phenomenon than so far assumed.
- Published
- 2012
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