Multiphoton confocals work by using an infrared laser at double or triple the wavelength necessary to excite a fluorophore. When two or three photons interact with the fluorophore at the same time, it is excited and emits fluorescence. The advantage of infrared light is that it can penetrate deep in tissues, unlike visible light which scatters. Therefore, a multiphoton can image deep in thick samples – provided the emitted signal is strong enough to be captured! It helps if the sample is cleared. Miltenyi TRIM The Miltenyi TRIM is a multiphoton confocal microscope equipped with two overlapping tuneable infrared lasers (680 to 1300nm) and a fixed line at 1064nm. This microscope can be configured upright as well inverted, giving complete flexibility of sample access. It has a 10x, 20x, 25x and 40x lenses, as well as 11 photoreceptors. This microscope has multiple filter sets to detect many dyes and fluorescent proteins. The TRIM is also capable of imaging the structure of the imaged tissue using two label-free modes: 1) through second harmonics, -a process that does not require dyes but relies on autofluorescence; and 2) Raman microscopy -which determines the molecular composition of a sample based on photon-induced specific chemical bond excitation. Special applications and features: Multiphoton imaging goes deep in sample Upright and inverted microscope Second Harmonics to detect autofluorescence in the tissue and signal context Raman/CARS microscopy for molecular identification. Raman works specially well with fatty molecules Resonant scanner mode for fast imaging Location: IRR Translational Imaging Hub, contact IRR.Imaging@ed.ac.uk for access. This article was published on 2024-07-08
