Publications associées à LEPA: From Proteomics to Energy Conversion

Controlled Formation of Nanoribbons and Their Heterostructures via Assembly of Mass-Selected Inorganic Ions

Control of nanomaterial dimensions with atomic precision through synthetic methods is essential to understanding and engineering of nanomaterials. For single-layer inorganic materials, size and shape controls have been achieved by self-assembly and surface ...

Wiley-V C H Verlag Gmbh2024

Advances in High-Speed, Multiparametric Atomic Force Microscopy

Santiago Harald Andany

After decades of technological advancements, high-speed atomic force microscopy (HS-AFM) has emerged as a powerful technique for visualizing dynamic processes. At the nanoscale, the AFM provides valuable insights into the sample by sensing minute interacti ...

EPFL2024

Identification of human milk oligosaccharide positional isomers by combining IMS-CID-IMS and cryogenic IR spectroscopy

Thomas Rizzo, Ahmed Ben Faleh, Stephan Warnke, Ali H Abikhodr, Vasyl Yatsyna

High-resolution ion mobility spectrometry (IMS) coupled with cryogenic infrared spectroscopy has proven to be a powerful technique for the identification of oligosaccharides. However, the need for an extensive database, combined with the scarcity of pure s ...

2023

New Approach for the Identification of Isobaric and Isomeric Metabolites

Thomas Rizzo, Ahmed Ben Faleh, Stephan Warnke, Ali H Abikhodr, Teun Van Wieringen

The structural elucidation of metabolite molecules is important in many branches of the life sciences. However, the isomeric and isobaric complexity of metabolites makes their identification extremely challenging, and analytical standards are often require ...

2023

Combining ion mobility spectrometry and cryogenic ion spectroscopy with enzymatic digestion/synthesis for the study of N-linked glycans

Irina Märki

Glycans play an essential role in numerous physiological and pathological processes of living organisms. Despite their significant biological relevance, glycobiology remains one of the least explored fields of biochemistry. The intrinsic isomeric complexit ...

EPFL2023

Investigations on Caesium Dispersion and Molybdenum Coating on SPIDER Components

Michele Fadone

SPIDER is the 100 keV full-size Negative Ion Source prototype of the ITER Neutral Beam Injector, operating at Consorzio RFX in Padova, Italy. The largest Negative Ion Source in the world, SPIDER generates an RF driven plasma from which Deuterium or Hydroge ...

2023

CVD of MoS2 single layer flakes using Na2MoO4 - impact of oxygen and temperature-time-profile

Andreas Stemmer, Christian Wäckerlin

Two-dimensional (2D) materials are of great interest in many fields due to their astonishing properties at an atomic level thickness. Many fundamentally different methods to synthesize 2D materials, such as exfoliation or chemical vapor deposition (CVD), h ...

Royal Soc Chemistry2023

Standard-Free Quantification of Dicarboxylic Acids: Case Studies with Salt-Rich Effluents and Serum

Christian Ludwig, Daniil Salionov, Sasa Bjelic

The present study evaluates the ionization efficiency (IE) of linear and branched C2–C14 dicarboxylic acids (DCAs) by electrospray ionization (ESI) under different conditions. The influence of the concentration of organic modifier (MeOH); mobile phase addi ...

2022

A neural probe to sample brain fluid in nanoliter volumes for quantitative molecular studies

Joan Teixidor

Neural functions operate in tightly controlled conditions that are mediated by multiple electrical and chemical phenomena. Brain disorders such as Parkinson's Disease and Alzheimer's Disease perturb these conditions and cause a loss of neurons, which impai ...

EPFL2022

A New Strategy Coupling Ion-Mobility-Selective CID and Cryogenic IR Spectroscopy to Identify Glycan Anomers

Thomas Rizzo, Ahmed Ben Faleh, Robert Paul Pellegrinelli, Stephan Warnke, Priyanka Bansal, Eduardo Carrascosa Casado, Lei Yue

Determining the primary structure of glycans remains challenging due to their isomeric complexity. While high-resolution ion mobility spectrometry (IMS) has recently allowed distinguishing between many glycan isomers, the arrival-time distributions (ATDs) ...

2022

Gentle nano-electrospray ion source for reliable and efficient generation of microsolvated ions

Oleg Boyarkine, Vladimir Kopysov, Andrei Zviagin

We present herein the design of a nano-electrospray ion source capable of reliable generation of large quantities of microsolvated ions. The source is based on a triple molecular skimmer scheme and can be quickly tuned to generate bare ions or their ionic ...

AIP Publishing2022

Identification of Mobility-Resolved N-Glycan Isomers

Thomas Rizzo, Ahmed Ben Faleh, Robert Paul Pellegrinelli, Stephan Warnke, Priyanka Bansal

Glycan analysis has evolved considerably during the last decade. The advent of high-resolution ion-mobility spectrometry has enabled the separation of isomers with only the slightest of structural differences. However, the ability to separate such species ...

AMER CHEMICAL SOC2022

Identification of Isomeric Biomolecules by Infrared Spectroscopy of Solvent-Tagged Ions

Oleg Boyarkine, Andrei Zviagin

The difference in functionality of many isomeric biomolecules requires their analytical identification for life science studies. We present a universal approach for quantitative identification of different small- to medium-sized isomeric biomolecules that ...

AMER CHEMICAL SOC2022

Cryo-EM structure of native human thyroglobulin

Henning Paul-Julius Stahlberg

The thyroglobulin (TG) protein is essential to thyroid hormone synthesis, plays a vital role in the regulation of metabolism, development and growth and serves as intraglandular iodine storage. Its architecture is conserved among vertebrates. Synthesis of ...

Nature Research2022

Photoisomerization of Linear and Stacked Isomers of a Charged Styryl Dye: A Tandem Ion Mobility Study

Eduardo Carrascosa Casado

The photoisomerization behavior of styryl 9M, a common dye used in material sciences, is investigated using tandem ion mobility spectrometry (IMS) coupled with laser spectroscopy. Styryl 9M has two alkene linkages, potentially allowing for four geometric i ...

AMER CHEMICAL SOC2021

Analyzing glycans cleaved from a biotherapeutic protein using a combination of ion mobility spectrometry and cryogenic ion spectroscopy

Natalia Yalovenko

The characterization of biomolecules plays a central role in biomedical research. The development of state-of-the-art technologies is needed to make such analyses faster, more sensitive, and more accurate. While mass spectrometry continues to play a centra ...

EPFL2021

A gas phase approach for glycan analysis: Combining ultrahigh-resolution ion mobility spectrometry with cryogenic vibrational spectroscopy

Ahmed Ben Faleh

The last decades have been punctuated by the development of revolutionary analytical technologies that have enabled the analysis of biomolecular structures and unraveled the roles they play in biological systems. However, certain classes of biomolecules re ...

EPFL2021

Detection of trace metals in biogas using extractive electrospray ionization high-resolution mass spectrometry

Christian Ludwig, Mohamed Tarik

On-line measurements of metal emissions in energy conversion systems at very low concentrations are difficult to perform using existing techniques. Metals are of high importance due to their detrimental impact on human health, the environment and various i ...

Pergamon-Elsevier Science Ltd2021

Charging and ion ejection dynamics of large helium nanodroplets exposed to intense femtosecond soft X-ray pulses

Daniela Rupp, Camila Bacellar Cases Da Silveira, Christoph Bostedt

Ion ejection from charged helium nanodroplets exposed to intense femtosecond soft X-ray pulses is studied by single-pulse ion time-of-flight (TOF) spectroscopy in coincidence with small-angle X-ray scattering. Scattering images encode the droplet size and ...

SPRINGER HEIDELBERG2021

Constraining the response factors of an extractive electrospray ionization mass spectrometer for near-molecular aerosol speciation

Yandong Tong, Julia Schmale, Imad El Haddad

Online characterization of aerosol composition at the near-molecular level is key to understanding chemical reaction mechanisms, kinetics, and sources under various atmospheric conditions. The recently developed extractive electrospray ionization time-of-f ...

2021