Publications associées à Optimizing the size and surface properties of polyethylene glycol (PEG)-gold nanoparticles by intense x-ray irradiation

Second harmonic scattering of nanoparticles: A journey into the electrical double layer

In aqueous solutions, a charged surface causes the redistribution of nearby ions. The ion layers formed are known as the electrical double layer (EDL), and are widespread in many systems involving electrochemistry, colloidal science, biomedicine, and energ ...

EPFL2024

Characterization of a flexible a-Si:H detector for in vivo dosimetry in therapeutic x-ray beams

Sylvain Dunand, Nicolas Würsch, Jonathan Emanuel Thomet, Luca Massimiliano Antognini, Matthew James Large

BackgroundThe increasing use of complex and high dose-rate treatments in radiation therapy necessitates advanced detectors to provide accurate dosimetry. Rather than relying on pre-treatment quality assurance (QA) measurements alone, many countries are now ...

Wiley2024

Stabilizing Polymer Coatings Alter the Protein Corona of DNA Origami and Can Be Engineered to Bias the Cellular Uptake

Maartje Martina Cornelia Bastings, Hugo José Rodriguez Franco, Jorieke Weiden

With DNA-based nanomaterials being designed for applicationsincellular environments, the need arises to accurately understand theirsurface interactions toward biological targets. As for any materialexposed to protein-rich cell culture conditions, a protein ...

AMER CHEMICAL SOC2023

Cholesterol-Containing Liposomes Decorated With Au Nanoparticles as Minimal Tunable Fusion Machinery

Francesco Stellacci, Paulo Henrique Jacob Silva, Ester Canepa, Giulia Rossi

Membrane fusion is essential for the basal functionality of eukaryotic cells. In physiological conditions, fusion events are regulated by a wide range of specialized proteins, operating with finely tuned local lipid composition and ionic environment. Fusog ...

WILEY-V C H VERLAG GMBH2023

Modulation of the nanoscale motion rate of Candida albicans by X-rays

Sandor Kasas, María Inés Villalba

IntroductionPatients undergoing cancer treatment by radiation therapy commonly develop Candida albicans infections (candidiasis). Such infections are generally treated by antifungals that unfortunately also induce numerous secondary effects in the patient. ...

Frontiers Media SA2023

Trap-and-Track for Characterizing Surfactants at Interfaces

Olivier Martin, Jeonghyeon Kim

Understanding the behavior of surfactants at interfaces is crucial for many applications in materials science and chemistry. Optical tweezers combined with trajectory analysis can become a powerful tool for investigating surfactant characteristics. In this ...

2023

Frequency and time domains interactions in nanophotonics

Andrei Kiselev

In this thesis, we discuss the problems of scattering and optical manipulation related to nanosystems of different complexities. The multipolar decomposition method is used to represent scattering processes in nanosystems as a series of elementary excitati ...

EPFL2023

Revealing the complexity of ultra-soft hydrogel re-swelling inside the brain

Stéphanie Lacour, Michael Shur, John Martin Kolinski, Outman Akouissi, Olivier Didier Christian Rizzo

The brain is an ultra-soft viscoelastic matrix. Sub-kPa hydrogels match the brain's mechanical properties but are challenging to manipulate in an implantable format. We propose a simple fabrication and processing sequence, consisting of de-hydration, patte ...

2023

Class Specific Feature Disentanglement and Text Embeddings for Multi-label Generalized Zero Shot CXR Classification

Seyedbehzad Bozorgtabar

Robustness of medical image classification models is limited by its exposure to the candidate disease classes. Generalized zero shot learning (GZSL) aims at correctly predicting seen and unseen classes and most current GZSL approaches have focused on the s ...

Springer International Publishing Ag2023

Jahn-Teller effects in initial and final states: high-resolution X-ray absorption, photoelectron and Auger spectroscopy of allene

Majed Chergui, Luca Longetti, Thomas Roland Barillot, Camila Bacellar Cases Da Silveira, Rebecca Ann Ingle, Daniel Hollas, Ludmila Maria Diniz Leroy

Carbon K-edge resonant Auger spectra of gas-phase allene following excitation of the pre-edge 1s -> pi* transitions are presented and analysed with the support of EOM-CCSD/cc-pVTZ calculations. X-Ray absorption (XAS), X-ray photoelectron (XPS), valence ban ...

ROYAL SOC CHEMISTRY2023

Ion-bridges and lipids drive aggregation of same-charge nanoparticles on lipid membranes

Francesco Stellacci, Zekiye Pelin Güven, Giulia Rossi

The control of the aggregation of biomedical nanoparticles (NP) in physiological conditions is crucial as clustering may change completely the way they interact with the biological environment. Here we show that Au nanoparticles, functionalized by an anion ...

ROYAL SOC CHEMISTRY2022

Medipix4, a high granularity four sides buttable pixel readout chip for high resolution spectroscopic X-ray imaging at rates compatible with medical CT scans

Viros Sriskaran

Medipix4 is the latest member in the Medipix/Timepix family of pixel detector chips aimed at high rate spectroscopic X-ray imaging using high-Z materials. The chip address the limitations of conventional hybrid pixel detectors for X-ray imaging. Its predec ...

EPFL2022

Plasmon-induced near-infrared fluorescence enhancement of single-walled carbon nanotubes

Giulia Tagliabue, Amirmostafa Amirjani, Ardemis Anoush Boghossian, Sayyed Hashem Sajjadi, Shang-Jung Wu, Alessandra Antonucci, Theodoros Tsoulos

Single-walled carbon nanotubes (SWCNTs) emit near-infrared (NIR) fluorescence that is ideal for optical sensing. However, the low quantum yields diminish the sensor’s signal-to-noise ratio and limits the penetration depths for in vivo measurements. In this ...

2022

Low and high frequency electromagnetic forces: numerical modelling and practical applications

Marco Riccardi

The understanding and manipulation of nanoscale analytes is a central theme in nanotechnology and has been one of the main driving forces behind the development of this field as we know it today. Furthermore, such a technology has the potential to also rev ...

EPFL2022

DNA-based biomaterials for nanoscale controlled modulation of immune cells

Alice Comberlato

Recent advances in the field of nanomaterials demonstrated how their use for vaccination can drastically improve immune responses, mainly by enhancing delivery and uptake of vaccine components. However, our understanding of the connections between presenta ...

EPFL2022

Disentangling Light- and Temperature-Induced Thermal Effects in Colloidal Au Nanoparticles

Majed Chergui, Lijie Wang, Davood Zare

We present temperature-dependent (from room temperature to 80 degrees C) absorption spectra of Au/SiO2 core-shell nanoparticles (NPs) (core diameter: similar to 25 nm) in water in the range from 1.5 to 4.5 eV, which spans the localized surface plasmon reso ...

AMER CHEMICAL SOC2022

Strategic Insights into Engineering Parameters Affecting Cell Type-Specific Uptake of DNA-Based Nanomaterials

Maartje Martina Cornelia Bastings, Alice Comberlato, Hugo José Rodriguez Franco, Marianna Mainardi Koga

DNA-based nanomaterials are gaining popularity as uniform and programmable bioengineering tools as a result of recent solutions to their weak stability under biological conditions. The DNA nanotechnology platform uniquely allows decoupling of engineering p ...

American Chemical Society2022

Molecular insights into the electrical double layer of colloidal oxide particles obtained through second harmonic scattering

Marie Bischoff

Photocatalytic applications play an essential role in the search for alternative energy sources and environmental decontamination techniques. It is of fundamental interest to understand on a molecular level the aqueous solid/liquid interface, where photoca ...

EPFL2022

Ion temperature spectroscopic measurements in high rotation discharges by means of X-ray diagnostic at JET

Henri Weisen

Measurement of the X-ray spectra of the He-like Ni ions (Ni26+) and their dielectronic satellites (Ni25+, Ni24+, and Ni23+) plays a crucial role in determination of electronic and ion temperature of plasma in the JET device. Because n >= 3 satellites of Ni ...

2022

Learning to sample in Cartesian MRI

Thomas Sanchez

Magnetic Resonance Imaging (MRI) is a non-invasive, non-ionizing imaging modality with unmatched soft tissue contrast. However, compared to imaging methods like X-ray radiography, MRI suffers from long scanning times, due to its inherently sequential acqui ...

EPFL2022