Two-photon fluorescence microscopy

Bowman R.D., Kneas K.A., Demas J.N., Periasamy A., Conventional, Confocal And Two-Photon Fluorescence Microscopy Investigations of Polymer-Supported Oxygen Sensors, J. Microscopy 2003 211 112-120. 

So P. T. C., French T., Yu W. M., Berland K. M., Dong C. Y. and Gratton E. (1996) Two-Photon Fluorescence Microscopy Time-Resolved and Intensity Imaging, in Wang X. F. and Herman B. (Eds), Fluorescence Imaging Spectroscopy and Microscopy, Chemical Analysis Series, Vol. 137, John Wiley Sons, New York, pp. 351-74. 

Two-photon fluorescence microscopy has also been used with good effect in the near-IR. For example, Ferguson et al.r24> at the University of Strathclyde have used 270 fsec pulses from a titanium sapphire (Ti sapphire) laser at 790 nm to observe visible fluorescence from dyes in zebra fish larvae and erythrocytes. The high depth and lateral definition afforded by the two-photon process and confocal microscopy are useful here. Also, the use of near-IR excitation minimizes photobleaching. 

Hopt, A., and Neher, E. 2001. Highly nonhnear photodamage in two-photon fluorescence microscopy. Biophys. J. 80 2029-36. 

Ogilvie, J. R, Debarre, D., Solinas, X., Martin, J.-L., Beaurepaire, E., and Joffre, M. 2006b. Use of coherent control for selective two-photon fluorescence microscopy in live organisms. Opt. Exp. 14(2) 759-66. 

Chapter 2 Using Two-Photon Fluorescence Microscopy to Study Chemical... 

A number of works investigated the interaction between niosomes and human skin. With niosomes prepared from Ci2 alcohol polyoxyethylene ether and cholesterol, vesicular structures of about 100 nm size have been observed between the first and second layers of human corneocytes 48 h after incubation as well as in the deeper strata of the skin [37], The authors concluded that the structures visualized in the deeper regions could be vesicles reorganized from individual molecules that penetrated the skin. In another study, electron micrographs illustrated that niosomes containing surfactants and cholesterol affected only the most superficial corneocytes. Moreover, two-photon fluorescence microscopy confirmed that fluorescent probe encapsulated in niosomes was confined to the intercellular spaces within the apical stratum corneum layers [56]. 

FIGURE 2.7 Two-photon fluorescence microscopy of amyloid plaque (red) and surrounding neurons (green) in the brain of a mouse model of Alzheimer s. Numerous neuronal abnormalities, including swelling and decreased densities of spines (arrow in c), could be detected. 

Koepsell Fi, Koepsell Fi./nWvo two-photon fluorescence microscopy opens a newarea for investigation ofthe excretion of cationic drugs in the kidney. Kidney int 2007 72 387-388. 

This review describes some of the recent developments in materials which exhibit enhanced two-photon absorption that can initiate photopolymerization or up-converted emission. Various optical methods including femtosecond time-resolved pump-probe experiments to characterize the two-photon properties are discussed. Finally, the applications of two-photon processes to optical power limiting, up-converted lasing, 3-D data storage, 3-D micro-fabrication, two-photon fluorescence microscopy and bio-imaging, and two-photon photodynamic therapy are presented. 

L.A. Bagatolli and E. Gratton. Two-photon fluorescence microscopy of coexisting lipid domains in giant unilamellar vesicles of binary lipid mixtures. Biophys. 

C.Y. Dong, K. Konig, P.T.C. So, Charactarizing point spread fucntions of two-photon fluorescence microscopy in turbid media, J. Biomed. Opt. 8, 450-459 (2003)... 

Winter and co-workers elucidated the interaction between lipidated Ras protein and membrane and investigated the distributiOTi of Ras proteins in membrane microenvironments using two-photon fluorescence microscopy on giant unilamellar vesicles (GUVs) and tapping mode atomic force microscopy (AFM)... 

Figure 11.12 A comparison between confocal and two-photon fluorescence microscopy in confocal microscopy fluorescence is excited throughout the sample while in two-photon excitation it is restricted to the confocal region around the focal point of the laser...

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)... 

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