PhD thesis: Detection of nanoplastics with ultraviolet nanophotonics

The intensive use of plastic materials has given rise to an alarming pollution linked to the presence of micro- and nanoplastics. The latter have dimensions of less than 1 µm, making them an even greater threat to biodiversity and human health. While current analysis methods are limited to particles larger than 5 µm, the detection of nanoplastics remains a major challenge.

This PhD project aims to break new ground in the quantitative detection of nanoplastics by exploiting time-resolved ultraviolet (UV) autofluorescence. Plastics emit intrinsic autofluorescence when illuminated in the UV, providing superior sensitivity to current Raman and infrared spectroscopies. The central objective is to improve detection sensitivity thanks to this autofluorescence property, targeting particles as small as 30 nm in diameter. A further original feature is the ability to differentiate between types of plastic by exploiting their autofluorescence lifetime.

Developing this approach requires the development of suitable characterization methods, as well as a deeper understanding of the UV photophysics of nanoplastics. The project aims to fill this gap by exploiting joint developments in spectroscopy, nanophotonics and the synthesis of calibrated plastic nanoparticles. The project builds on our recent progress and preliminary results.

This novel UV approach promises enhanced sensitivity, the ability to detect nanoscale particles, and a direct, label-free application ideal for in situ scenarios. The project will open up new perspectives for the detection of nanoplastics, helping to better understand and quantify this invisible pollution.

The Institut Fresnel is a research state laboratory based in Marseille / France, devoted to research and higher education with affiliation to both CNRS and Aix Marseille University. Institut Fresnel is seeking to recruit talented, enthusiastic young scientists who are highly motivated to boost their research career in the areas of nanosciences, biosensing, and nano/biotechnologies.

Jerome Wenger’s group has acquired a wide expertise in the nanoscale control of light fields in plasmonic nanostructures and its application to enhance fluorescence spectroscopy applications.      

Web Link       www.jeromewenger.com     

To apply for a PhD fellowship, candidates must hold or be in the final stages of completing an internationally-recognized Master-equivalent degree in physics, chemistry or engineering. Experience in experimental and/or theoretical research on nano-optics and/or biophotonics will be highly appreciated, but is not mandatory. No restrictions of citizenship apply to the PhD fellowship.

Soft skills: Strong motivation for optics, curiosity for nanosciences, English for science, autonomy, analytical and critical thinking, writing skills, presentation skills