Superoxide Production under Soft X-ray Irradiation of Liquid Water.

Soft X-rays behave like particles with high linear energy transfer, as they deposit a large amount of their energy in the nanometric range, triggered by inner-shell ionization. In water, this can lead to the formation of a doubly ionized water molecule (HO) and the emission of two secondary electrons (photoelectron and Auger electron). Our focus lies on detecting and quantifying the superoxide (HO°) production via the direct pathway, i.

Electronic Structure and Solvation Effects from Core and Valence Photoelectron Spectroscopy of Serum Albumin.

X-ray photoelectron spectroscopy of bovine serum albumin (BSA) in a liquid jet is used to investigate the electronic structure of a solvated protein, yielding insight into charge transfer mechanisms in biological systems in their natural environment. No structural damage was observed in BSA following X-ray photoelectron spectroscopy in a liquid jet sample environment. Carbon and nitrogen atoms in different chemical environments were resolved in the X-ray photoelectron spectra of both solid and solvated BSA.

Experimental determination of the curvature-induced intra-wall polarization of inorganic nanotubes.

Inspired by a natural nano-mineral known as imogolite, aluminosilicate inorganic nanotubes are appealing systems for photocatalysis. Here, we studied two types of synthetic imogolites: one is completely hydrophilic (IMO-OH), while the other has a hydrophilic exterior and a hydrophobic interior (IMO-CH), enabling the encapsulation of organic molecules. We combined UV-Vis diffuse reflectance spectroscopy of imogolite powders and X-ray photoelectron spectroscopy of deposited imogolite films and isolated nanotubes agglomerates to obtain not only the band structure, but also the quantitative intra-wall polarization of both synthetic imogolites for the first time.

A microfluidic dosimetry cell to irradiate solutions with poorly penetrating radiations: a step towards online dosimetry for synchrotron beamlines.

Synchrotron radiation can induce sample damage, whether intended or not. In the case of sensitive samples, such as biological ones, modifications can be significant. To understand and predict the effects due to exposure, it is necessary to know the ionizing radiation dose deposited in the sample.

Soft X-ray Radiation and Monte Carlo Simulations: Good Tools to Describe the Radiation Chemistry of Sub-keV Electrons.

The description of the biological effects of ionizing radiation requires a good knowledge of the dose deposition processes at both the cellular and molecular scales. However, experimental studies on the energy deposition specificity of sub-keV electrons, produced by most radiations, including high-energy photons and heavy ions, are scarce. Soft X-rays (0.

VEGF (Vascular Endothelial Growth Factor) Functionalized Magnetic Beads in a Microfluidic Device to Improve the Angiogenic Balance in Preeclampsia.

Preeclampsia is a hypertensive pregnancy disease associated with a massive increase in sFlt-1 (soluble form of the vascular endothelial growth factor 1) in the maternal circulation, responsible for angiogenic imbalance and endothelial dysfunction. Pilot studies suggest that extracorporeal apheresis may reduce circulating sFlt-1 and prolong pregnancy. Nonspecific apheresis systems have potential adverse effects because of the capture of many other molecules.