Alternatives to perfluorinated compounds for water-repellent and oil-repellent treatments of textiles used for NRBC personal body protection
Finding alternatives to fluorinated compounds (PFAS) involves very diverse application areas. Among them, the treatment of technical textiles to make them water- and oil-repellent is a major challenge for manufacturing protective clothing against both aqueous and oily contaminants. Our laboratory is developing such alternatives by covalently grafting molecules onto fibers selected from those already used for technical textiles. The thesis will focus on experimental work with two components. The first component will consist of improving and qualifying, at a semi-industrial level, the water- and oil-repellent properties already obtained and qualified according to current standards (water and oil droplet sliding, slow impregnation of oil droplets) using our nanometric chemical coatings. The second component will be dedicated to optimizing the weave structure, in conjunction with the chemical treatment, to determine the optimal weave based on the desired properties. The work will be carried out in close contact with a technical textile manufacturer and with ENSAIT in Roubaix.
Micro-needles functionalized with aptamers for the optical detection of cortisol
Compact, wearable medical devices, by offering autonomous and continuous monitoring of biomarkers, open the way to precise monitoring of pathologies outside of care centers and to a personalized therapeutic approach. The thesis project aims to develop wearable sensors based on microneedles (MNs) made of biomaterials for the minimally invasive detection of cortisol in the interstitial fluid (ISF) of the skin. Cortisol is one of the important biomarkers of physical and psychological stress, and is linked to the development of chronic diseases. ISF, a very rich source of biomarkers, offers an alternative to blood as a minimally invasive biofluid for cortisol quantification, and can be continuously analyzed by microneedle devices. Thus, swelling microneedles made of crosslinked biopolymer hydrogel have been developed at CEA-Leti over the last three years for ISF collection and analysis. The objective of the project will be to functionalize the hydrogel with a cortisol-sensitive aptamer molecular beacon, whose fluorescence will be activated in the specific presence of this metabolite, drawing on the expertise of the DPM NOVA team. Wearable optical sensors based on cortisol-sensitive MN patches will be designed, exploring two configurations: MN patches entirely made of hydrogel, and hybrid MN patches comprising an optical waveguide biopolymer and a cortisol-sensitive hydrogel coating. Different needle/waveguide shapes will be explored to optimize the fluorescence detection performance of the biosensors. The ability of the devices to puncture a skin model, sample artificial ISF, and detect the target will also be evaluated. The study will include biocompatibility tests, as well as a comparison with current methods for measuring serum cortisol by immunoassay.
Diamond Beam Monitor for FLASH Therapy
Optimizing tumor dose delivery requires advanced treatment techniques. One promising approach focuses on refining beam delivery through ultra-high dose rate irradiation (UHDR), with temporal optimization being a key strategy. Recent studies highlight the effectiveness of FLASH irradiation using electrons, demonstrating similar tumor inhibition capabilities as gamma rays but with reduced damage to healthy tissue. To fully harness this potential, we are exploring innovative beams, such as high energy electron beams, which offer instantaneous dose rates and per-pulse doses many times higher than those produced by conventional radiation sources. However, accurately monitoring and measuring these beams remains a significant challenge, primarily due to the high dose rate.
The Sensors and Instrumentation Laboratory (CEA-List) will collaborate with the Institut Curie as part of the FRATHEA project. We propose the development of a novel diamond-based monitor, connected to associated electronics, to achieve precise measurements of dose and beam shape for high-rate electron and proton beams. Interdisciplinary experimental techniques, including diamond growth, device microfabrication, device characterization under radioactive sources, and final evaluation with electron beam, will be used for prototyping and testing the diamond beam monitor.
As part of the FRATHEA project, the PhD student will work on the following tasks:
• Growth of optimized single-crystal chemical vapor-deposited (scCVD) diamond structures
• Characterization of the electronic properties of the synthesized diamond materials
• Estimation of the dose response characteristics of a simplified prototypes
• Fabrication of a pixelated beam monitor
• Participation in beam times at the Institut Curie (an other institutes) for devices testing in clinical beams
Required Skills:
• Strong background in semiconductor physics and instrumentation
• Knowledge of radiation detectors and radiation-matter interactions
• Ability to work effectively in a team and demonstrate technical rigor in measurements
Additional Skills:
• Knowledge of electronics, including signal processing, amplifiers, oscilloscopes, etc.
• Familiarity with device fabrication and microelectronics
• Previous experience working with diamond materials
Profile:
• Master's level (M2) or engineering school, with a specialization in physical measurements
• Adherence to radiation protection regulations (category B classification required)
PhD Duration: 3 years
Start Date: Last semester of 2025
Contact:
Michal Pomorski : michal.pomorski@cea.fr
Guillaume Boissonnat: guillaume.boissonnat@cea.fr
Radiological large-scale accident dosimetry: use of EPR spectroscopy for population triage by measurements of smartphone screens
In the event of a large-scale radiological emergency involving sources of external irradiation, methods are needed to identify which members of the population have been exposed and require priority care. To date, there are no operational methods for such sorting. Smartphone touch screen lenses retain traces of ionizing radiation through the formation of so-called “radiation-induced” defects.Measuring and quantifying these punctual defects, in particular by electron paramagnetic resonance (EPR) spectroscopy, makes itpossible to estimate the dose deposited in the glass, and thus the exposure associated with irradiation. The thesis work proposed herefocuses in particular on the alkali-aluminosilicate glasses used in cell phone touch screens, which are currently the best candidates fordeveloping new measurement capabilities in the context of accidents involving large numbers of victims.
We will focus in particular on identifying point defects as a function of the glass model used in smartphones by simulating EPR spectra in order to optimize the proposed dosimetry method.
Characterization of motor recovery in stroke patients during a BCI-guided rehabilitation
Brain-computer interfaces (BCIs) make it possible to restore lost functions by allowing individuals to control external devices through the modulation of their brain activity. The CEA has developed a BCI technology based on the WIMAGINE implant, which records brain activity using electrocorticography (ECoG), along with algorithms for decoding motor intentions. This technology was initially tested for controlling robotic effectors such as exoskeletons and spinal cord stimulation devices to compensate for severe motor impairments. While this initial paradigm of substitution and compensation is promising, a different application potential is now emerging: functional recovery through BCI-guided rehabilitation. Current literature suggests that BCIs, when used intensively and in a targeted manner, can promote neural plasticity and, in turn, improve residual motor abilities. In particular, ECoG-based implanted BCIs could offer significant therapeutic outcomes. The objective of this thesis is therefore to assess the potential of CEA's BCI technology to enhance patients' residual motor functions through neural plasticity.
This work will be approached through a rigorous and multidisciplinary scientific methodology, including a comprehensive review of the scientific literature, the setup and execution of experimentations with patients, the algorithmic development of tools for monitoring and analyzing patient progress, and the publication of significant results in high-level scientific journals.
This PhD is intended for a student specializing in biomedical engineering, with expertise in signal processing and the analysis of complex physiological data, as well as experience in Python or Matlab. A strong interest in clinical experimentation and neuroscience will also be required. The student will work within a multidisciplinary team at CLINATEC, contributing to cutting-edge research in the field of BCIs.
The development of surfaces that limit microbial proliferation is a crucial public health issue. In the context of manned flights to remote destinations such as low Earth orbit, the Moon and possibly Mars, biological contamination represents a significant threat to crew health and the preservation of space equipment. The microflora carried by the crew in enclosed habitats constitutes an unavoidable risk, accentuated by prolonged periods of isolation and dependence on closed environment life support systems. In addition to the risks to astronauts' health, biocontamination is known to damage critical equipment on board spacecraft. Furthermore, micro-organisms exposed to the space environment can develop resistance and mutate, transforming benign microbes into pathogens. To mitigate these risks, effective measures, such as filtration systems and self-decontaminating surfaces that limit bacterial proliferation, need to be put in place. The MATISS experiment (2016-2025), in which the SyMMES and PRISM laboratories were involved, explored the use of hydrophobic coatings to reduce biocontamination on board the ISS, but further improvements are needed, in particular to find alternative solutions to perfluorinated agents and antibiotics, but also applicable to a wide range of materials. Such advances could have a wide range of applications beyond space, including food safety (packaging), implantable materials, drinking water treatment, public transport hygiene, etc. The aim of this collaborative thesis between SyMMES and CEA-Leti in Grenoble is to develop sustainable antimicrobial coatings free from harmful substances, by exploring different functionalization methods, such as the formation of self-assembled monolayers, electropolymerization on conductive materials, and in a highly original way by implementing a new cold atmospheric plasma deposition method, suitable for large surfaces, and above all applicable to a wide range of different materials.
Embedded systems for natural acoustic signals analysis while preserving privacy
The PhD topic aims at developping Embedded systems to record and analyze natural acoustic signals. When targeting city deployement, the privacy issue is raised: how can we keep a satisfactory analysis level while never record or transmit human voices?
Hyperpolarized Xenon NMR to probe the functionality of biological barriers
Optical pumping of xenon, giving rise to an intense NMR signal, is a specialty of the LSDRM team. Xenon, which is soluble in biological media, has a wide range of chemical shifts, which we use here to study the properties of cell barriers. Numerous pathologies stem from an alteration of these barriers.
In this thesis, we aim to develop a specific methodology using hyperpolarized xenon to study the functionality (integrity, permeability, selectivity) of biological barriers, using in vitro and in vivo spectroscopy and imaging. The thesis will be divided into two parts: in vitro, the aim will be to develop a device and NMR protocols for studying model cell assemblies; in vivo, studies on rodents will enable us to assess xenon's ability to reach organs more or less close to the lungs while maintaining its polarization, and to measure kinetics across barriers. This topic will enable major instrumental and methodological advances, as well as a deepening of our knowledge of selective transport processes at different biological barriers.
Development of a Multilayer Encapsulation System for the Production of Core-Shell Microcapsules Suitable for Organoid Growth
Every year, 20 million people worldwide are diagnosed with cancer, with 9.7 million succumbing to the disease (Kocarnik et al., 2021). Personalized treatment could significantly reduce the number of deaths. This thesis addresses this challenge by proposing the development of organoids derived from patient biopsies to optimize treatments.
The bioproduction of encapsulated cells in biopolymers is a rapidly growing field, with applications in personalized medicine, research, drug screening, cell therapies, and bioengineering. This thesis aims to contribute to these fields by focusing on the multilayer encapsulation of cells in biopolymers with a wide range of viscosities.
The inner layer (core) provides an optimal environment for the maturation and survival of cells or organoids, while the outer layer (shell) ensures mechanical protection and acts as a filtering barrier against pathogens.
This new thesis aims to design, develop, and study—both analytically and numerically—the architecture of a dual-compartment nozzle for the high-frequency production of monodisperse core-shell capsules. It builds upon a previous thesis completed in 2023, which focused on the detailed characterization and development of a predictive model for the generation of single-layer microcapsules using centrifugal force alone.
The formation and ejection mechanisms of multilayer capsules are complex, involving the rheological properties of biopolymers, centrifugal force, surface tension, and interfacial dynamics. The nozzle architecture must account for these properties.
The first part of this thesis will focus on understanding the multilayer formation and ejection mechanisms of microcapsules as a function of nozzle geometry. This will allow the prediction and control of capsule formation based on the rheological properties of the biopolymers. The second part will involve developing an automated system for the aseptic production of capsules. Finally, biological validation will assess the functionality and reliability of the developed technology.
To achieve the objectives of this study, the candidate will first conduct analytical and numerical studies, design the ejection nozzles, and leverage the laboratory's expertise for their fabrication. Fluidic tests on prototypes will help optimize the design, leading to the development and testing of a fully operational microcapsule production system.
The ideal candidate will have a background in physics, engineering, and fluid mechanics, with a strong inclination for experimental approaches. Prior experience in microfluidics or biology would be a valuable asset.
New rapid diagnostic tool for sepsis: microfluidic biochip for multi-target detection by isothermal amplification
Sepsis is among the main cause of death across the world, and is caused by severe bacterial infection but can also originate from viruses, fungi or even parasites. In order to drastically increase survival rates, a rapid diagnostic and appropriate treatment is of paramount importance. The commercially available tools for nucleic acid detection by qPCR are able to sense multiple targets. However, these multiplexed analyses arise from the accumulation of analysis channels or reaction chambers where only one target can be detected. The original sample has to be divided, resulting in a loss of sensibility since a smaller amount of targets is available in channels or chambers.
In order to tackle the question of “How to detect multiple targets without a loss in sensibility?”, the PhD candidate will have to develop a multiplexed detection in a single reaction chamber by localized immobilization of LAMP primers (Loop-mediated isothermal amplification) on a solid substrate like COC or glass.
The expected outcome is a biochip allowing for real-time and fast (minutes) detection of several molecular DNA targets including: primers design and selection, primers immobilization on surface, integration of the biochip into a microfluidic cartridge and data collection and management for fluorescence detection of targets.
This innovative work will provide the PhD candidate with strong skills in diverse scientific domains such as molecular biology, surface functionalization, modelling and simulation, in a very multidisciplinary working environment.