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Updated: May 24, 2026

Dual-Color Fluorescence Cross-Correlation Spectroscopy to Study Protein-Protein Interaction and Protein Dynamics in Live Cells
Published on: December 11, 2021
Nonlinear correlation spectroscopy (NLCS)
Matthias Geissbuehler1, Luigi Bonacina, Vladislav Shcheslavskiy
1Laboratoire d'Optique Biomédicale LOB, École Polytechnique Fédérale de Lausanne (EPFL), Switzerland. matthias.geissbuehler@epfl.ch
Abstract:
We present a novel concept for optical spectroscopy called nonlinear correlation spectroscopy (NLCS). NLCS analyses coherent field fluctuations of the second and third harmonic light generated by diffusing nanoparticles. Particles based on noncentrosymmetric nonlinear materials such as KNbO(3) show a strong second as well as third harmonic response. The method and the theory are introduced and experimental NLCS results in fetal calf serum are presented showing the promising selectivity of this technique for measurement in complex biological environments.
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