Project R-13113

Non-linear optical and time-dependent fluorescence properties of molecular probes reveal the phases of surrounding lipid membranes: a multiscale modeling approach (Research)

Organic fluorophores embedded in lipid bilayers can nowadays be described by a multiscale computational approach. We developed over the years a methodology to characterize probes in view of their different positions, orientations, conformational versatilities, and (non) linear optical as well as fluorescence properties when they are embedded in model membranes. Combining different length and time scales, a full description of the probe led to novel insight into the effect of the environments. In this talk, computations on Laurdan, indocarbocyanine and azobenzene derived probes are presented, sketching how a multiscale approach based on extended molecular dynamics and hybrid quantum mechanics-molecular mechanics frameworks can predict probes' optical properties like two-photon absorption, second harmonic generation, and fluorescence lifetime and time resolved fluorescence anisotropy. We show not only how computer simulations can explain particular confocal experiments by analysing the localization and orientation of probes in different membrane phases, but also how computation can uncover novel functionalities of well-used probes, which might change the accepted view upon them.

19 September 2022 - 21 September 2022