Title: Studies on two-photon absortion and fluorescence
Directors: ZHANG Sanjun and ANTOINE Rodolphe
Discipline: Physics/Chemistry
Status: Ongoing Project
Starting date: 2026
Directors
Summary
This proposal addresses the need for superior exogenous markers in near-infrared two-photon excited fluorescence (TPEF) bioimaging. Traditional organic dyes suffer from low photostability and limited two-photon absorption (TPA) cross-sections. Conversely, metal nanoclusters (NCs) feature a unique core-shell structure yielding TPA cross-sections three to five orders of magnitude higher than commercial dyes. However, their biological application is restricted by low two-photon fluorescence quantum yields (TPEQY) and poorly understood structure-property relationships.
To solve these issues, the project outlines four core objectives:
- Mapping the exact relationship between TPA cross-sections and atomically precise NC structures.
- Developing methods (e.g., rigidification, alloying, fluorophore coupling) to increase TPEF quantum yield.
- Elucidating the unique TPEF luminescence origin and relaxation pathways using ultrafast transient absorption spectroscopy.
- Designing high-performance, biocompatible TPEF probes for intracellular pH sensing
The two-year agenda pairs a French partner focusing on structural synthesis, mass spectrometry, and nonlinear optics with a Chinese partner specializing in ultrafast spectroscopy and biological imaging.