Jerome Wenger NanoBioPhotonics

Institut Fresnel is organizing a special day to celebrate this anniversary: https://www.fresnel.fr/bicentenaire-fresnel/

Chaired by Patrice Genevet and co-chaired by Jerome Wenger, the Nanophotonics and Micro/Nano Optics International Conference 2020 is proudly featuring an outstanding list of 12 outstanding invited speakers. The conference attendance is limited to 250 persons, so check the NANOP 2020 conference website and apply enough in advance to secure your participation.

Detecting proteins in the UV range is appealing to take advantage of their natural tryptophan fluorescence and rule out all the issues related with external fluorescence labelling. However, proteins feature a much lower fluorescence brightness than conventional fluorescent dyes. This is where nanophotonics can improve the detection sensitivity.

In a recent Nano Letter article, we report the first demonstration of single protein UV fluorescence enhancement using aluminum zero-mode waveguides nanoapertures. Dedicated strategies were developed to overcome the technical challenges of working in the UV range. This involves optimizing the UV aluminum nanostructures fabrication, counteracting the metal photocorrosion, dealing with the limited photostability of proteins and developing robust analysis tools to extract useful information out of noisy traces.

This unprecedented detection of single protein fluorescence with UV plasmonics paves the way for interrogating individual proteins in their native state and at physiological concentrations.

Also freely available on ArXiv 1909.08227

Ultraviolet plasmonics is a burgeoning scientific field where the strong molecular absorption bands in the UV range are combined with the intense electromagnetic fields of plasmonic nanostructures. This powerful combination is highly promising to promote surface-enhanced spectroscopy and catalysis. However, in a recent J Phys Chem Lett article, we find that the photocorrosion of aluminum can severely hamper UV plasmonics applications but appropriate protection solutions can circumvent this issue.

Significance:

- We highlight the occurrence of the aluminum photocorrosion effect and explain its origin by the nonlinear absorption of water in the UV leading to the production of hydroxyl radicals.

- Different protection strategies are developed to prevent the photocorrosion based on scavengers for reactive oxygen species and additional polymer layers, achieving a 10-fold increase in the UV power range with no visible corrosion effect.

Also freely available on ArXiv 1907.11003

Since beginning of September, our team welcomes François Iv to help us in the protein research within the framework of the ERC TryptoBoost project.