Three-dimensional fluorescence microscopy in two-photon excitation regime

In our laboratory, within the framework of a national INFM project, we have realised a two-photon excitation fluorescence microscope part of a multipurpose architecture including also lifetime imaging and fluorescence correlation spectroscopy modules. The core of the architecture are a mode-locked Ti:sapphire laser (Tsunami 3960, Spectra Physics Inc., CA) pumped by a high-power (5 W, 532 nm) laser (Millennia V, Spectra Physics Inc., CA) and an ultracompact scanning head, Nikon PCM2000 (Nikon Instr., Italy). Three-dimensional confocal images of fluorophores excitable in UV and the blue region are shown. We are currently characterising the architecture in terms of point-spread-function and biological system viability.