Circularly polarised luminescence for two-photon microscopy: designing chiral supramolecular materials

Bioimaging has become an essential tool for biological studies, driving the need for efficient optical probes and spectroscopic methods to reveal deeper structural and functional properties. The current linear microscopic techniques face limitations such as photobleaching, tissue damage, scattering, auto-fluorescence and low tissue penetration. These challenges can be mitigated using multiphoton microscopy, combined with circularly polarized light detection. Extracting the chiroptical signals can eliminate autofluorescence and improve signal-to-noise ratio, while two-photon excitation reduces tissue damage and improves penetration depths. However, the lack of effective chiral optical probes limits the full potential of this method. The CPL2 project aims to address this gap by developing advanced chiral fluorescent probes based on supramolecular aggregates for two-photon spectroscopy and microscopy. The project focuses on designing these probes and testing their efficiency through a multidisciplinary approach that integrates theoretical modelling, preparation of chiral aggregates, and two-photon spectroscopic and microscopic characterization. CPL2 will be carried out at University of Parma over a period of 24 months under the supervision of Prof. C. Sissa, an expert in two-photon spectroscopy and theoretical modelling of supramolecular aggregates. Prof. Sissa’s expertise complements that of Dr. S. Nizar, the experienced researcher, who specializes in polarimetric characterization of aggregates. The experienced researcher will also undertake a secondment at Durham University to test the most promising materials for two-photon circularly polarized luminescence. Beyond its scientific contributions, this project offers the experienced researcher valuable expertise in nonlinear spectroscopy and theoretical modelling, strengthening her profile for a future position as an independent researcher in the interdisciplinary academic environment of the EU.