Prithu Roy Awarded Aix Marseille University Best Thesis Prize 2024
Following his success in winning the ED352 prize, Prithu Roy has been honored with the prestigious Prix de Thèse AMU 2024 at the official awards ceremony held on April 4th.
This annual distinction, presented by President Éric Berton during a major scientific event, recognizes outstanding doctoral research at Aix-Marseille University. Each year, the award celebrates 16 exceptional new PhDs accross all areas for science (only 1 or 2 per year in physics and engineering) and also pays tribute to eminent researchers named Doctor Honoris Causa of the university.
Prithu’s doctoral thesis, titled “Achieving Ultimate Sensitivity of Label-Free Autofluorescence Spectroscopy of Single Proteins with Deep Ultraviolet Nanophotonics,” is available for consultation on HAL repository.
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Breaking the Low Concentration Barrier of Single-Molecule Fluorescence Quantification to the Sub-Picomolar Range
Our article entitled “Breaking the low concentration barrier of single-molecule fluorescence quantitation to the sub-picomolar range” has recently been published in Small Methods.
Until now, the concentration range for effective single-molecule fluorescence detection was largely restricted to the concentrations above 50 pM, overlooking the immense potential of the single-molecule fluorescence for biosensing applications at sub-picomolar sensitivity.
In our work, we present a simple and effective modification to a confocal microscope setup that pushes the detection limit of fluorescence lifetime correlation spectroscopy (FLCS) down to 0.1 pM, overcoming the so-called low concentration barrier without the need for complex instrumentation or preconcentration techniques.
Main elements of significance:
- Adding a diaphragm on the laser excitation beam achieves a large detection volume together with a high fluorescence brightness per molecule. This is the key to push the sensitivity towards sub-picomolar concentrations.
- For the first time, we clearly discuss the physical parameters setting the lower the limit of quantification in FLCS and we introduce a universal figure of merit allowing to compare between experimental configurations.
- We demonstrate the effectiveness of our approach by monitoring the interaction dynamics of biotin-streptavidin binding, a highly relevant biochemical system yet challenging to measure on conventional systems due to its exceptionally high affinity.
These results open new avenues for applying single-molecule fluorescence detection to biosensing at sub-picomolar concentrations, with significant implications for biological and medical diagnostics.
Open access at Small Methods and available on the repository HAL 05043006.
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Jerome Wenger Elected Fellow of Optica
We are glad to announce that Jerome Wenger has been elected to the rank of Fellow of Optica (formerly OSA) in recognition of his contributions to the field of optics and photonics. The citation reads: “For pioneering contributions to nanophotonics and optical nanoantennas to enhance single molecule fluorescence.”
As ChatGPT writes it: "This prestigious honor reflects Jerome’s impactful research at the intersection of nanophotonics and single-molecule spectroscopy. His work on designing and using optical nanoantennas to control light at the nanoscale has opened new frontiers for enhancing fluorescence signals, enabling more sensitive and precise measurements in biological and chemical systems.
Being named a Fellow is a significant milestone, reserved for individuals who have made distinguished contributions to optics and photonics. Optica Fellows represent the top 10% of the society’s membership, selected through a rigorous peer review process. Congratulations, Jerome, on this well-deserved recognition!"
Thanks ChatGPT that is so heart-warming 😊
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Watching lanthanide nanoparticles one at a time
Our recent work, “Watching lanthanide nanoparticles one at a time: characterization of their photoluminescence dynamics at the single nanoparticle level,” has been accepted for publication in Nanoscale.
Lanthanide nanoparticles (LnNPs) are gaining attention for their potential in biosensing and bioimaging, but until now, their photoluminescence behavior at the single nanoparticle level remained poorly understood. In this study, we go beyond traditional ensemble measurements by using fluorescence correlation spectroscopy (FCS) and photoluminescence burst analysis to explore the emission dynamics of Sm and Eu-based LnNPs with single-particle sensitivity and microsecond resolution. Our results reveal key insights into the brightness, emission stability, and the number of emitting centers within individual nanoparticles.
Most importantly, we demonstrate the ability to detect and analyze single LnNPs—an exciting step forward for high-precision sensing and imaging applications. This work helps bridge the gap between ensemble-averaged spectroscopy and single-molecule techniques, opening new possibilities for the use of LnNPs in next-generation bioanalytical tools.
Read the preprint on ArXiv 2412.07443
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Bye X-twitter, we're leaving and won't look back
Our account @Photonicsnano was essentially on hold over the last year, waiting to see how X/twitter evolves. Thanks Elon for making things evidently clear by using a sign instantly recognisable by (almost) everybody on this planet.
We don't recognize ourselves in the values displayed by X/twitter and its president. Our account has been definitely closed. At least I can think of my grandfather without feeling ashamed about myself.