Article
Chemistry, Multidisciplinary
Tingting Li, Chengen Ho, Mengxi Han, Pai Peng, Junjie Chen, Yong Huang, Bin Li, Qiang Chen
Summary: Effectively regulating the release behavior of bactericides to avoid both too fast and too slow release is a major challenge. In this study, indole was encapsulated into three types of zeolites with different topologies. The zeolite encapsulation systems showed a much slower release rate of indole compared to indole impregnated onto a counterpart zeolite, thus avoiding undesirable release behavior.
Article
Biophysics
Maria de los Angeles Ramirez, Elisa Bindini, Paolo Moretti, Galo J. A. A. Soler Illia, Heinz Amenitsch, Patrizia Andreozzi, Maria Grazia Ortore, Sergio E. Moya
Summary: The evolution of mesoporous silica nanoparticles (MSNs) in simulated body fluid was studied, and it was found that unmodified MSNs showed structural changes at high concentrations, while PEGylated MSNs remained more stable.
COLLOIDS AND SURFACES B-BIOINTERFACES
(2022)
Article
Chemistry, Inorganic & Nuclear
Min Li, Jian Xiao, Lin Chen, Bo Ren, Zhanjun Liu, Yuexin Guo, Yali Wang
Summary: This study reveals the effect of particle size of mesoporous silica nanoparticles (MSNs) on the diffusion distance of ibuprofen (IBU). MSNs with different particle sizes were synthesized and characterized. The optimal unilateral diffusion distance of IBU in MSNs was found to be about 50 nm. Hollow mesoporous silica nanoparticles (HMSNs) were prepared to increase the loading of IBU, and the optimal drug loading was achieved when the shell thickness was equal to the optimal diffusion distance.
JOURNAL OF SOLID STATE CHEMISTRY
(2023)
Review
Polymer Science
Thierry Woignier, Juan Primera, Adil Alaoui, Philippe Dieudonne, Laurent Duffours, Isabelle Beurroies, Sylvie Calas-Etienne, Florence Despestis, Annelise Faivre, Pascal Etienne
Summary: Silica aerogels are materials with exceptional characteristics, such as ultra-low density, high surface area, high porosity, high adsorption, and low thermal conductivity. The fractal structure of silica aerogels can vary depending on synthesis conditions, with the fractal dimension typically ranging between 1.6 and 2.4. X-ray and neutron scattering measurements have shown that silica aerogels can exhibit a fractal structure over one or more than two orders of magnitude in length.
Article
Polymer Science
Katsumi Hagita, Tetsuo Tominaga, Ryota Yamamoto, Takuo Sone
Summary: In this study, a particle-mesh-based two-dimensional reverse Monte Carlo method was used to investigate the three-dimensional structure of nanoparticle aggregates in rubber tire treads. It was found that the characteristic cluster sizes of silica nanoparticles in end-modified styrene-butadiene rubber treads were smaller than those in nonmodified SBR treads. The deformation of the nanoparticles during stretching was modeled using a series of two-dimensional scattering patterns, and a high-connectivity cluster analysis was used to characterize the morphologies of the nanoparticles.
Article
Chemistry, Physical
Bruno Chal, Lucian Roiban, Guilhem P. Baeza, Karine Masenelli-Varlot, Jacques Jestin, Bernard Yrieix, Genevieve Foray
Summary: Nanostructured silica plays a key role in industrial-scale materials, especially in structuring food, drugs, and rubber, and contributes to the development of sustainable energy materials. The hygrothermal stability is crucial for insulation materials, as their properties depend on nanostructures.
JOURNAL OF MATERIALS CHEMISTRY A
(2021)
Article
Chemistry, Multidisciplinary
Meiling Zhang, Jean-Marie Poumirol, Nicolas Chery, Herve Rinnert, Alaa E. Giba, Remi Demoulin, Etienne Talbot, Fuccio Cristiano, Teresa Hungria, Vincent Paillard, Fabrice Gourbilleau, Caroline Bonafos
Summary: We successfully demonstrate the experimental realization of plasmonic hyperdoped Si nanocrystals embedded in silica by a combination of sequential low energy ion implantation and rapid thermal annealing. We find that phosphorus dopants are incorporated into the nanocrystal cores at concentrations up to six times higher than P solid solubility in bulk Si. We explain the nanocrystal growth at high P doses as a result of Si recoiling atoms generated in the matrix by P implantation, which enhance Si diffusivity and provide the Si nanocrystals.
Article
Chemistry, Multidisciplinary
A. Czajka, G. Liao, O. O. Mykhaylyk, S. P. Armes
Summary: This study focuses on the formation of polymer/silica nanocomposite particles through surfactant-free aqueous emulsion polymerization, monitoring key parameters using various techniques to understand the process.
Article
Energy & Fuels
Tao Chen, Suyuan Yu, Yu Cheng Liu
Summary: The study investigates the effects of Soret diffusion on hydrogen-air edge flame propagation and diffusion-chemistry interaction through simulation. It demonstrates that Soret diffusion significantly influences the relationships between flame displacement speed and flame curvature, stretch rate, and scalar dissipation rate. Additionally, Soret diffusion weakens the chemical reaction component in edge flame propagation and affects the diffusion of hydrogen and hydrogen-2 in opposite ways.
Article
Polymer Science
Ya Xuan Thong, Xiaodong Li, Xi Jiang Yin
Summary: This study analyzed the physical, chemical, mechanical, and thermal properties of RPUF composites prepared using industrially-used flame retardants TMCP or TCPP, expandable graphite (EG), and silica aerogel. The results showed that EG performed the best among the three flame retardants.
JOURNAL OF APPLIED POLYMER SCIENCE
(2022)
Article
Engineering, Chemical
Yubai Liu, Thomas Pelster, Ting-Tai Lee, Yujun Wang, Guangsheng Luo
Summary: The growth process of silica nanoparticles prepared by adding sulfuric acid dropwise into waterglass was investigated. Three stages of growth were observed, and the hydrolysis and condensation reactions were analyzed. The particle size changes in the growth stage were fitted using the LSW model, and the formation of pore structures was studied.
Article
Materials Science, Multidisciplinary
Patrick E. J. Saloga, Tina Rybak, Andreas F. Thuenemann
Summary: In this study, a simple one-pot procedure was reported to obtain aqueous zinc oxide (ZnO) nanoparticle dispersions from ZnO nanoparticles dispersed in cyclohexane. Polysorbate 80 (Tween 80) was used as a phase transfer agent and colloidal stabilizer. The particle sizes could be controlled by adjusting the incubation time of the dispersion.
ADVANCED ENGINEERING MATERIALS
(2022)
Article
Chemistry, Physical
Hope A. Michelsen, Matthew F. Campbell, K. Olof Johansson, Ich C. Tran, Paul E. Schrader, Ray P. Bambha, Emre Cenker, Joshua A. Hammons, Chenhui Zhu, Eric Schaible, Anthony van Buuren
Summary: In this study, soot particles in a laminar co-flow ethylene-air diffusion flame were characterized using small-angle X-ray scattering (SAXS). The results showed that the soot particles in the middle of the flame have an established core-shell structure, while the particles higher and lower in the flame have smoother surfaces. SAXS measurements were more sensitive than laser-induced incandescence (LII) in detecting the incipient and young soot particles, especially in the low flame regions where the LII signal was negligible.
Article
Materials Science, Characterization & Testing
Qiang Tian, Jiayi Sun, Mark Julian Henderson, Xuegang Huang, Na Li, Jeremie Courtois, Laszlo Almasy
Summary: Relaxation mechanisms of shake gels, composed of silica nanoparticles and poly(ethylene oxide), were investigated using small-angle X-ray scattering and dynamic light scattering methods. Results showed that the gel network quickly relaxes within the first 10-20 minutes after shake-induced gelation, and then slowly reaches a quiescent structure after 1 hour.
Article
Chemistry, Physical
Yongliang Wang, Baoqiang Liu, Ruiyang Chen, Yunfei Wang, Zhidong Han, Chunfeng Wang, Ling Weng
Summary: Silica nanoparticles were added to polypropylene composites with ammonium polyphosphate and pentaerythritol to enhance flame retardancy. The dispersion of nano-silica in the composite matrix was favorable and improved the flame retardancy. The synergistic effects between nano-silica and intumescent flame retardant were studied using various tests, and the results showed improved flame retardancy with the addition of nano-silica.
Article
Physiology
Jesus G. Ovejero, Luca Fusi, So-Jin Park-Holohan, Andrea Ghisleni, Theyencheri Narayanan, Malcolm Irving, Elisabetta Brunello
Summary: In this study, the researchers found that cooling the rat heart muscle can release myosin motors, which affects the strength and speed of contraction. Additionally, they observed similar structural changes in relaxed conditions when cooling was applied.
JOURNAL OF GENERAL PHYSIOLOGY
(2022)
Article
Polymer Science
Rintaro Takahashi, Theyencheri Narayanan, Shin-ichi Yusa, Takahiro Sato
Summary: This study reports the self-assembly kinetics of polymer vesicles probed by time-resolved small-angle scattering. The formation process of polymer vesicles was found to exhibit different kinetic behavior compared to conventional low-molecular-weight surfactants. This finding is significant for understanding the formation mechanism of polymer vesicles.
Article
Chemistry, Multidisciplinary
Theyencheri Narayanan, Michael Sztucki, Thomas Zinn, Jerome Kieffer, Alejandro Homs-Puron, Jacques Gorini, Pierre Van Vaerenbergh, Peter Boesecke
Summary: This article describes the new technical features and enhanced performance of the ID02 beamline with the Extremely Brilliant Source (EBS) at the ESRF. The beamline enables static and kinetic investigations of a broad range of systems in different size scales and time ranges. Additionally, it allows for multispeckle X-ray photon correlation spectroscopy measurements and relaxation of collimation conditions, resulting in higher flux throughput and lower background. The article highlights the importance of these developments in enabling structural, dynamic, and kinetic investigations of out-of-equilibrium soft matter and biophysical systems.
JOURNAL OF APPLIED CRYSTALLOGRAPHY
(2022)
Article
Chemistry, Physical
Lauren Matthews, Theyencheri Narayanan
Summary: Self-assembled lyotropic phases, particularly microemulsions, play a crucial role in formulation science. By systematically increasing the bending modulus of the surfactant film, microemulsions can be made to swell and form various different phases.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Chemistry, Physical
J. Royes, V. A. Bjornestad, G. Brun, T. Narayanan, R. Lund, C. Tribet
Summary: Photoswitchable surfactants are used in the design of light-responsive colloids and self-assemblies. This study investigates the intermediate lipid-surfactant assemblies formed during fast isothermal photo-triggered transitions. The experiments reveal that the transient assemblies detected during the photo-triggered kinetics are similar to the stationary states. Additionally, the reorganization speed of surfactant-enriched assemblies is faster than that of lipid-enriched ones.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Instruments & Instrumentation
Ann-Christin Jacobsen, Aleksei Kabedev, Patrick D. Sinko, Johan E. Palm, Christel A. S. Bergstrom, Alexandra Teleki
Summary: This study introduced the intrinsic lipolysis rate (ILR) as a surface area-independent approach to compare lipid digestibility. The impact of surfactant concentration on the apparent lipolysis rate and lipid structure on ILR was systematically investigated. The calculated ILR of pure acylglycerols was successfully used to accurately predict the IRL of binary lipid mixtures.
DRUG DELIVERY AND TRANSLATIONAL RESEARCH
(2023)
Article
Chemistry, Physical
Thomas Zinn, Lewis Sharpnack, Theyencheri Narayanan
Summary: The orientation behavior and translational dynamics of spherical magnetic silica-nickel Janus colloids in an external magnetic field have been studied. The research findings reveal that the particle dynamics is dominated by Brownian motion for weak applied fields and low volume fractions. However, higher fields result in more complex structural changes and chain-like configurations. The study also demonstrates anisotropic particle dynamics at higher volume fractions and strong magnetic fields.
Article
Chemistry, Multidisciplinary
Giovanni Marco Saladino, Ronak Kakadiya, Shaquib Rahman Ansari, Alexandra Teleki, Muhammet Sadaka Toprak
Summary: Superparamagnetic iron oxide nanoparticles (SPIONs) play a dominant role in various biomedical applications, including magnetic separation, drug delivery, diagnostics, and hyperthermia treatments. In this study, superparamagnetic nanoclusters (SP-NCs) with high unit magnetization and diameters up to 400 nm were synthesized using conventional or microwave-assisted solvothermal methods. The choice of synthesis route and capping agent significantly influenced the particle size, SP-NC size, surface chemistry, and magnetic properties. The SP-NCs were then coated with a silica shell doped with a fluorophore to provide fluorescence properties and high stability. The heating efficiency studies demonstrated the potential of these synthesized SP-NCs in hyperthermia treatment. The enhanced magnetically-active content, fluorescence, magnetic property, and heating efficiency of SP-NCs offer promising opportunities for biomedical applications.
NANOSCALE ADVANCES
(2023)
Article
Chemistry, Physical
Lauren Matthews, Theyencheri Narayanan
Summary: This article presents the recent progress of synchrotron scattering methods for elucidating the self-assembly pathways in dilute surfactant systems. The improved source brilliance and advanced detectors enable time-resolved structural investigations of low contrast and dilute surfactant solutions in the millisecond range. The results demonstrate that spontaneous self-assembly occurs in dilute solutions without any pre-existing motifs.
COLLOID AND POLYMER SCIENCE
(2023)
Article
Chemistry, Physical
Anja F. Hoermann, Artem Feoktystov, Theyencheri Narayanan, Jeremie Gummel, Michael Gradzielski
Summary: A quantitative analysis of small-angle x-ray scattering on a mixed surfactant system of tetradecyldimethylamine oxide (TDMAO) and lithium perfluorooctanoate (LiPFO) was conducted using densitometry, conductimetry, and contrast-variation small-angle neutron scattering. The study found that the vesicles formed contained a higher mole fraction of TDMAO than predicted by Regular Solution Theory (RST), and the unimer concentration of LiPFO was significantly higher than predicted by RST. Additionally, the vesicle bilayer was asymmetric with a higher fraction of LiPFO on the outside. These findings are important for understanding similar mixed surfactant vesicle systems and their applications.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Theyencheri Narayanan, William Chevremont, Thomas Zinn
Summary: Recently, fourth-generation synchrotron sources with higher brightness and coherence compared to previous sources have opened up new possibilities for small-angle X-ray scattering (SAXS) and X-ray photon correlation spectroscopy (XPCS). These advancements in beam properties and detector technology have improved the angular resolution and enabled the probing of equilibrium dynamics over broader scales. This article showcases the performance of SAXS and XPCS using the Extremely Brilliant Source at the European Synchrotron Radiation Facility, while also addressing the challenge of radiation damage in sample analysis.
JOURNAL OF APPLIED CRYSTALLOGRAPHY
(2023)
Article
Chemistry, Multidisciplinary
Angelo Pommella, Pablo Griffiths, Gildas Coativy, Florent Dalmas, Surojit Ranoo, Annette M. M. Schmidt, Francoise Mechin, Julien Bernard, Thomas Zinn, Theyencheri Narayanan, Sylvain Meille, Guilhem P. P. Baeza
Summary: By investigating the heating mechanism in multi-block copolymers filled with Fe nanoparticles and subjected to an oscillatory magnetic field, the physical origin of the secondary heating mechanism in magnetic hyperthermia is revealed. It is found that the enormous drop of viscosity at the polymer melting temperature enables motion of nanoparticles that generates additional heat through friction.
Article
Chemistry, Physical
Jenny Johannesson, Malhar Manik Pathare, Mathias Johansson, Christel A. S. Bergstrom, Alexandra Teleki
Summary: Pharmaceutical formulation of oral dosage forms faces challenges due to the low solubility of new drug candidates. A Pickering emulsion stabilized by stearic acid and silica nanoparticles was developed as an alternative to surfactants, enabling the controlled release of lipophilic drugs. The emulsion was transformed into a gel with suitable rheological properties for 3D printing tablets, allowing for rapid lipid digestion and drug release in the small intestine.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Physiology
Marco Caremani, Luca Fusi, Massimo Reconditi, Gabriella Piazzesi, Theyencheri Narayanan, Malcolm Irving, Vincenzo Lombardi, Marco Linari, Elisabetta Brunello
Summary: Skeletal muscle contraction is triggered by an increase in intracellular calcium concentration. The release of folded motors and the conformation of thick filaments are both influenced by calcium. A new intermediate regulatory state of myosin motors appears at low levels of calcium activation.
JOURNAL OF GENERAL PHYSIOLOGY
(2023)
Article
Chemistry, Multidisciplinary
A. Gibaud, D. Younas, L. Matthews, T. Narayanan, K. Longkaew, I. U. Hageberg, Y. Chushkin, D. W. Breiby, B. Chattopadhyay
Summary: The formation of calcium carbonate (CaCO3) nanoparticles in the presence of polystyrene sulfonate (PSS) additive was studied using time-resolved small-angle X-ray scattering in a flow system that mimics home experimental conditions. It was found that the concentration of precursors at a fixed PSS concentration plays a key role in determining the size of the obtained nanoparticles. Wide-angle X-ray scattering experiments showed that the formed particles have the structure of vaterite.
JOURNAL OF APPLIED CRYSTALLOGRAPHY
(2023)
