Two-photon scanning microscopy

Picot, A., Baldeck, P.L., Grichine, A., et cd. (2008) Long-lived two-photon excited luminescence of water-soluble europium complex applications in biological imaging using two-photon scanning microscopy. Journal of the American Chemical Society, 130, 1532—1533. 

Picot, A., D Aleo, A., Patrice, L., Baldeck, P. L., Grichine, A., Duperray, A., Andraud, C., Maury, O., Long lived Two photon Excited Luminescence of Water soluble Europium Complex Applications in Biological Imaging Using Two photon Scanning Microscopy, J. Am. Chem. Soc. 2008, 130, 1532 1533. 

Figure 5.19 TEM image of nano-spheres prepared by (a) micro-emulsion or (c) sol-gel techniques, (b) Two-photon scanning microscopy of MDA-MB-231 cancer cells stained with anti-CFR conjugated nanoparticle, (d) Two-photon luminescence images of single silica nanoparticles. Adapted with permission from [124]. Copyright 2010, John Wiley and [125] Copyright 2008, Royal Society of Chemistry...

For samples thicker than the depth of field, the images are blurred by out-of-focus fluorescence. Corrections using a computer are possible, but other techniques are generally preferred such as confocal microscopy and two-photon excitation microscopy. It is possible to overcome the optical diffraction limit in near-field scanning optical microscopy (NSOM). 

Denk W (1994) Two-photon scanning photochemical microscopy—mapping ligand-gated ion-channel distri-... 

H. Kano, H.T.M. van der Voort, M. Schrader, G.M.R van Kampen, S.W. Hell, Avalanche photodiode detection with object scanning and image restoration provides 2-4 fold resolution increase in two-photon fluorescence microscopy. Bioimaging 4, 187 (1996)... 

Bhawalkar J D, Swiatkiewicz J, Pan S J, Samarabandu J K, Liou W S, He G S, Berezney R, Cheng P C and Prasad P N 1996 Three-dimensional laser scanning two-photon fluorescence confocal microscopy of polymer materials using a new, efficient upconverting fluorophore Scanning 18 562-6... 

Strickler J FI and Webb W W 1990 Two-photon excitation in laser scanning fluorescence microscopy Proc. SPIE 13948107-18... 

W. W. (1990) Two-photon laser scanning fluorescence microscopy. Science, 248, 73-76. 

Diaspro A, Chirico G, Federici F, Cannone F, Beretta S, Robello M (2001) Two-photon microscopy and spectroscopy based on a compact confocal scanning head. J Biomed Opt 6 300-310... 

Lifetime imaging can be implemented both in wide field and in scanning microscopes such as confocal microscopes and two-photon excitation microscopes. The most common implementations in time-domain fluorescence lifetime imaging microscopy (FLIM) are based on TCSPC [8, 9] and time-gating (TG) [2, 10],... 

As mentioned above, spectral imaging microscopy is a form of multidimensional fluorescent microscopy where a fluorescent emission spectrum is acquired at each coordinate location in the sample. This mode of imaging has been implemented for wide field, confocal, and two-photon laser scanning microscopy, and several excellent... 

Two-photon excitation provides intrinsic 3-D resolution in laser scanning fluorescence microscopy. The 3-D sectioning effect is comparable to that of confocal microscopy, but it offers two advantages with respect to the latter because the illumination is concentrated in both time and space, there is no out-of-focus photo-bleaching, and the excitation beam is not attenuated by out-of-focus absorption, which results in increased penetration depth of the excitation light. 

Guild, J. B., and Webb, W. W. 1995. Line scanning microscopy with two-photon fluorescence excitation. Biophys. J. 68 290a. 

Strickler JH, Wehh WW (1990) Two-photon excitation in laser scanning flnorescence microscopy. SPIE Proc 1398 107-118... 

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