Applications de la spectroscopie ultrarapide à l’étude de sondes locales d’environnement et d’interactions biomoléculaires

In the context of the present thesis, UV-Vis time-resolved spectroscopy was applied targeting the photophysics investigation of different environmentally sensitive molecular systems, but also as a biosensing approach to reveal molecular interactions or structural dynamics on much slower time scales (sec to min), using droplet microfluidics triggering structural relaxation through out-of-equilibrium initial conditions. I thus investigated on a three-axis-target spanning from 1) the in-depth investigation of the emissive properties of biosensors in order to allow their quantitative use in biomolecular interaction studies, to 2) the development of an original experimental approach to enable resolving the structural relaxation kinetics of an out-of-equilibrium distribution of biomolecular structures, and finally 3) the technological application of time resolved fluorescence for precise, rapid, cost effective, biomolecular interaction assays, appealing both for academic and industrial arenas.La spectroscopie UV-Vis résolue en temps a été appliquée à l'étude de différents systèmes moléculaires dont la photophysique est contrôlée par leur interaction avec l’environnement, mais aussi comme outil pour révéler des interactions moléculaires ou des dynamiques structurelles à des échelles de temps comparativement lentes (sec à min.), en utilisant la microfluidique de gouttes pour déclencher une relaxation structurale par des conditions initiales hors équilibre. J'ai appliqué cette approche selon trois axes allant de 1) l'étude approfondie des propriétés émissives des biosenseurs afin de permettre leur utilisation quantitative dans les études d'interactions biomoléculaires, à 2) le développement d'une approche expérimentale originale pour permettre la résolution la cinétique de relaxation structurelle d'une répartition hors équilibre des structures biomoléculaires, et enfin 3) l'application aux biotechnologies à haut débit de la fluorescence résolue en temps pour des analyses d'interactions biomoléculaires précises et rapides, pertinente à la fois pour les domaines académiques et industriels

Embedded Fluorescence Lifetime Determination for High-Throughput, Low-Photon-Number Applications

International audienc

Towards sensitive, high-throughput, biomolecular assays based on fluorescence lifetime

Time-resolved fluorescence detection for robust sensing of biomolecular interactions is developed by implementing Time Correlated Single Photon Counting in high-throughput conditions. Droplet microfluidics is used as a promising platform for the very fast handling of low-volume samples. We illustrate the potential of this very sensitive and cost-effective technology in the context of an enzymatic activity assay based on fluorescently-labeled biomolecules. Fluorescence lifetime detection by Time Correlated Single Photon Counting is shown to enable reliable discrimination between positive and negative control samples at a throughput as high as several hundred samples per second

Design, Implementation and Characterization of Time-to-Digital Converter on Low-Cost FPGA

The fourth volume titled ‘Sensors and Applications in Measuring and Automation Control Systems’ contains twenty four chapters with sensor related state-of-the-art reviews and descriptions of latest advances in sensor related area written by 81 authors from academia and industry from 5 continents and 20 countries: Australia, Austria, Brazil, Finland, France, Japan, India, Iraq, Italia, México, Morocco, Portugal, Senegal, Serbia, South Africa, South Korea, Spain, UK, Ukraine and USA. Coverage includes current developments in physical sensors and transducers, chemical sensors, biosensors, sensing materials, signal conditioning, energy harvesters and sensor networks

Towards Sensitive, High-Throughput, Biomolecular Assays Based on Fluorescence Lifetime

Time-resolved fluorescence detection for robust sensing of biomolecular interactions is developed by implementing Time Correlated Single Photon Counting in high-throughput conditions. Droplet microfluidics is used as a promising platform for the very fast handling of low-volume samples. We illustrate the potential of this very sensitive and cost-effective technology in the context of an enzymatic activity assay based on fluorescently-labeled biomolecules. Fluorescence lifetime detection by Time Correlated Single Photon Counting is shown to enable reliable discrimination between positive and negative control samples at a throughput as high as several hundred samples per second

Ultrafast photophysics of the environment-sensitive 4′-methoxy-3-hydroxyflavone fluorescent dye

The ESIPT reaction speed of 4′-methoxy-3-hydroxyflavone varies by 3 orders of magnitude depending on the H-bonding capabilities of its environment.</p