Two-photon fluorescence microscopy (2PM) / Fluorescence decay time (FLIM)
Anti-Pollution Matrix > Methods > Method list
> Two-photon fluorescence microscopy (2PM) / Fluorescence decay time (FLIM)
The Two-photon fluorescence microscopy combined with the determination of the fluorescence decay time (2PM/FLIM) is a non-invasive method that allows real-time analysis of cellular as well as extracellular structural information with subcellular resolution. Autofluorescence of 2PM is used for skin morphology analysis, allowing selective mapping of collagen fibers in the dermis for the further assessment of pollution-induced skin structural changes. This method can be applied ex vivo and in vivo [1-3].
The 2PM/FLIM has a resolution of 0.5 µm laterally and 1 µm vertically. It is currently the most specific method with the highest resolution for collagen studies.
- Characterization of the skin (thickness of different skin layers, collagen/elastin ratio, skin barrier disorder) 
- Structural analysis of skin layers in vivo for differentiation of skin textures dependent on age and sex 
- Determination of collagen/elastin ratio
- Assessment of the integrity of the skin barrier
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