Fluorescence microscopy chemistry

Y. Maekawa, Y. Suzuki, K. Maeyama, N. Yonezawa, M. Yoshida, Visualization of chemical modification of pore internal surface using fluorescence microscopy. Chemistry Lett, 33 (2), 150-151,2004. 

Fluorescent pH indicators offer much better sensitivity than the classical dyes such as phenolphthalein, thymol blue, etc., based on color change. They are thus widely used in analytical chemistry, bioanalytical chemistry, cellular biology (for measuring intracellular pH), medicine (for monitoring pH and pCC>2 in blood pCC>2 is determined via the bicarbonate couple). Fluorescence microscopy can provide spatial information on pH. Moreover, remote sensing of pH is possible by means of fiber optic chemical sensors. 

Confocal fluorescence microscopy has been extensively used in cell biology. Single living cells can indeed be studied by this technique visualization of organelles, distribution of electrical potential, pH imaging, Ca2+ imaging, etc. (Lemasters, 1996). Interesting applications in chemistry have also been reported in the fields of colloids, liquid crystals and polymer blends. 

This volume covers a wide range of fundamental topics in coal maceral science that varies from the biological origin of macerals to their chemical reactivity. Several chapters report novel applications of instrumental techniques for maceral characterization. These new approaches include solid l3C NMR, electron spin resonance, IR spectroscopy, fluorescence microscopy, and mass spectrometry. A recently developed method for maceral separation is also presented many of the new instrumental approaches have been applied to macerals separated by this new method. The contributions in this volume present a sampling of the new directions being taken in the study of coal macerals to further our knowledge of coal petrology and coal chemistry. 

Fluorescence microscopy techniques are now available which are capable of studying supramolecular interfacial assemblies with excellent spatial and temporal resolution as well as exceptional sensitivity. These methods were initially developed for use in cellular biology, but are finding increasing application in interfacial supramolecular chemistry. This trend is set to continue as methods in single-molecule spectroscopy and time-resolved microscopy evolve. 

Phimphivong, S. and Scott Saavedra, S. (1998) Terbium chelate membrane label for time-resolved, total internal reflection fluorescence microscopy of substrate-adherent cells. Bioconjugate Chemistry, 9, 350-357. 

Weis, R. M. (1991). Fluorescence microscopy of phospholipid monolayer phase transitions. Chemistry and Physics of Lipids 57 227-239. 

K.J. Stine and C.M. Knobler, Fluorescence Microscopy A Tool for Studying the Physical Chemistry of Interfaces, Ultramicroscopy 47 (1992) 23. (Review short introduction to fluorescence and fluorophores basic instrumentation for fluorescence microscopy and extensions to study dynamics and resonance energy transfer, confocal scanning microscopy results obtained with Langmuir monolayers.)... 

Nie, S.M., Chiu, D.T., and Zare, R.N. (1995) Real-time detection of single-molecules in solution by confocal fluorescence microscopy. Analytical Chemistry, 61, 2849-2857. 

It seems valuable to speculate on the potential future applications of lifetime-based sensing. In our opinion, the dominant advantages of lifetime-based sensing are that the measurements can be independent of the local probe concentration, and the decay time measurements are mostly self-calibrating. The insensitivity of the lifetime to the local probe concentration enables the use of lifetime-based sensing in flow cytometry (iiO), fluorescence microscopy 25,88,111-112, Lakowicz, J.R. et al. Cell Calcium, in press), and clinicsd chemistry 25,65-66,113, Lakowicz, J.R. et al. SPIE Proceedings 1993, Vol.1895, in press)... 

Figwe 7 Proliferation data (days 1-3) and fluorescence microscopy images (day 1) of NIH-3T3 cells on control tissue culture polystyrene (TOPS) and on Aims formed from RLP12. The scale bar represents 100 pm. Reproduced with permission from Charati, M. B. Ifkovits, J. L. Burdick, J. A. etal. Soft MatterZOOS, 5, 3412. Copyright 2009 Royal Society of Chemistry. 

Osborne, MA, Balasubramanian, S, Furey, WS, and Klenerman, D, Optically biased diffusion of single molecules studied by corfocal fluorescence microscopy. Journal of Physical Chemistry B 102 (1998) 3160-3167. 

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