X-ray Single Particle Imaging has the aim of imaging biomolecules without the need of crystallization. The invention of X-ray Free Electron Lasers (XFELs) provided the instruments for this imaging process, however the technique is still suffering from low signal to noise ratio. Retrieval of the orientation of the sample in the moment of photon-sample interaction would greatly improve the...
Marine microplastic pollution has emerged as a major global concern, with growing implications for both marine ecosystems and human health [1]. Polystyrene nanoparticles (PS-NPs) can induce significant biological responses, as demonstrated by combined in vivo and in vitro models. In zebrafish, exposure to PS-NPs resulted in marked changes in eye pigmentation patterns that were not associated...
Conical intersections (CIs) are regions of the potential energy landscape of a molecule where the electronic and nuclear degrees of freedom become strongly mixed and the Born–Oppenheimer approximation breaks down. CIs are ubiquitous features in the photophysics and photochemistry of molecules and can be considered as “doorways” through which the photoexcited wavepacket is efficiently funneled...
Proteins, constituting the virus structure, cover a wide and diverse range of functions. Spike glycoprotein (S) of SARS-CoV-2 is a notable example. As the largest structural protein of the virus, the S protein plays a crucial role in attaching to the host receptor ACE2 through its receptor-binding domain (RBD) [1]. The functionalities of these membrane proteins, such as cellular targeting and...
Imaging the structure and observing the dynamics of isolated proteins using single-particle X-ray diffractive imaging (SPI) is one of the potential applications of X-ray free-electron lasers (XFELs). Currently, SPI experiments on isolated proteins are limited by three factors: low signal strength, limited data and high background from gas scattering. The last two factors are largely due to the...
Picosecond-long x-ray pulses of moderate intensity and up to MHz CW repetition rate for time-resolved analysis of matter in the linear response regime are proposed for un upgrade operation of Elettra 2.0, now in construction as funded successor of the Elettra storage ring light source in Trieste, Italy. The scheme, based on the adoption of radiofrequency transverse deflecting cavities,...
Single particle imaging of biomolecules using Free electron lasers (FEL) is an imaging technique that has been under development since the dawn of FEL:s more than two decades ago. Due to the heavy ionisation, biomolecules exposed to FEL pulses explode. In a recent publication (Phys. Rev. Lett. 134, 128403 (2025)) we have described how we can harvest information about the molecular structure of...
A way to induce local damage to cancerous tissue is by using radiotherapy-amplifying bioagents doped with high-Z elements. This enables deep core-level ionisation during radiotherapy with X-rays above the K-edge threshold, significantly increasing radiation absorption. Core electron ejection from high-Z elements also triggers a cascade of secondary particles, amplifying damage.
We studied...
X-ray emission spectroscopy (XES) complements structural techniques like serial femtosecond crystallography (SFX) by providing insights into the electronic states at specific sites within a sample. At X-ray free-electron lasers, simultaneous SFX and XES measurements using a single pulse have already been performed — such as the determination of the oxidation states in metalloproteins. By using...
