Jobs and Fellowship Positions
Please note that position announcement can only be posted for BES members in good standing.
Send your announcement in a WORD file to the BES Office (info@bioelectrochemical-soc.org) and we will take care of the posting within 48 hours. PDF files are not accepted. The announcement will remain on the website for approximately for three (3) months.
Electroenzymatic biosensor for H2 detection
PhD position 2024-2027 - Marseille, France
Laboratory: Bioenergetics and Protein Engineering (BIP), CNRS, Aix-Marseille University - https://bip.cnrs.fr/groups/bip08/
Context : Within the current challenge of irreversible climate change, the search for CO2-neutral energy sources and carriers is essential. Thanks to its transient storage and restitution during peaks of energy needs via fuel cells, hydrogen appears to be a sustainable solution. However, being a light and explosive gas, hydrogen represents significant risks when stored in large quantities. The installation of reliable, sensitive and miniaturized sensors is therefore required to detect possible leaks. In nature, hydrogenases are very efficient and selective enzymes for H2 oxidation. We have shown that the membrane-bound Ni-Fe hydrogenase extracted from the bacterium Aquifex aeolicus has many of the essential characteristics to meet the requirements of an electrochemical H2 sensor.
Research description : Capitalizing on our fundamental knowledge of hydrogenase-based electrodes, this Ph.D position will aim at designing a sensitive and miniaturized H2 biosensor in different environmental conditions. In particular, it will address i) How to tune the immobilization of the enzyme toward the most favorable H2 oxidation catalysis under the operating conditions required by the H2 detection biosensor; ii) Which methodologies can be developed in order to overcome H2 mass transport limitation; iii) How to determine the relationship between the enzyme surface coverage, its spatial distribution at the electrode surface and the enzymatic activity. To answer this question in situ and operando methods will be implemented, and in particular confocal fluorescence microscopy coupled to electrochemistry; iv) How to increase the stability of the bioelectrodes under storage and turnover. Various parameters (purity and origin of the enzyme, T°, ionic strength, local pH, protection by additives in solution and/or on the electrode) will be evaluated, as well as different electrode structuration and chemical functionalities able to increase the stability of the immobilized enzyme while maintaining an activity compatible with the detection of H2; v) What is the impact of the geometry of the biosensor and its miniaturization on its performance. Different sensor geometries will thus be produced by 3D printing, making it possible to bring H2 in dissolved form in a buffer electrolyte but also in gaseous form.
In addition to the applicative proof of the enzymatic sensor, the research carried out as part of the thesis project
will improve fundamental knowledge on enzymatic behavior in different confined environments. It will also make it possible to bridge the gap with past developments in the laboratory on enzymatic noble metal free fuel cells, by ultimately considering the self-powering of the sensor.
Ph.D skills: The candidate should have a Masters’ degree in chemistry, with major interest in analytical chemistry. Background/interest in electrochemistry, in 3D printing, and willing to work in a multidisciplinary environment are highly welcome.
This Ph.D position is co-funded by Aix Marseille University (AMU) and “Agence-Innovation-Défense “(AID). European, UK and Swiss nationals can apply.
Applications: Candidates are invited to submit their CV, a motivation letter, copies of academic transcripts and degrees, and two recommendation letters by email to Elisabeth Lojou (lojou@imm.cnrs.fr).
Dead line 10th May 2024
Probing bioenergetics at single mitochondria by AFM-SECM microscopy
PhD position offer currently available at Paris Cite University, France
Summary : The goal of this project is to study bioenergetics activities at the scale of single organelles, the mitochondria, by using an ultra-sensitive electrochemical nano-imaging technique. Mitochondria are the "energy powerhouses” of living cells, synthesizing the chemical bioenergy fuel, ATP, under coupling with the activity of the enzymatic respiratory chain. Studying the efficiency of electron transport within the chain, via the oxidation of various coenzymes (NADH, quinone, cytochrome-c) with O2 as the final acceptor, provides information about the bioenergetics functioning of mitochondria in physio and pathological conditions. In this project, individual mitochondria will be functionally imaged, under different respiratory, redox and metabolic states, using the ultra-resolved and dual atomic force-electrochemical nanoscopy (AFM-SECM). This imaging technique is currently the only one capable of constructing a topographical image of a single living mitochondrion while simultaneously mapping its redox reactivity, at an unprecedented sub-particle scale.
Keyword: Nano-bioelectrochemistry, AFM-SECM imaging, mitochondria, respiratory chain
Host laboratory : Laboratory of Molecular Electrochemistry, UMR 7591 CNRS, Université Paris Cité, France. BIONANO team. Thesis supervisor: Dr. Arnaud Chovin. Co supervisor: Dr. Stéphane Arbault, Institute of Chemistry and Biology of Membranes and Nano-objects (CBMN), UMR 5248 CNRS, University of Bordeaux, France.
PhD funding : Application to IdEx ("Initiative d'Excellence") international doctoral grants at University Paris Cité. Exclusively available to Master 2 foreign students enrolled in universities outside of France. Candidate Profile : Master 2 degree in analytical or biological chemistry, biophysics or bioengineering. The candidate will have an affinity for interdisciplinary research, experimental work, and qualities of rigor, care and organization. Experience in electrochemistry, microscopy or instrumentation is a plus.
Contact : Candidates should send a CV and a letter of motivation by e‐mail to Arnaud Chovin and Stephane Arbault (arnaud.chovin@u‐paris.fr ; stephane.arbault@u-bordeaux.fr).
