Fluorescence confocal optical microscopy

Bonilla, G., Tsapatsis, M., Vlachos, D.G., and Xomeritakis, G. (2001) Fluorescence confocal optical microscopy imaging of the grain bormdary structure of zeolite... 

Zeolite membranes are commonly characterized by SEM, XRD. TEM, EPMA, SEM-EDX, TEM-EOS, and Nitrogen adsorption are also used to study the morphology, microstructure and composition of zeolite membranes. Usually single gas permeation, mixed gas separation, pervaporation and vapor permeation are performed to evaluate the properties of zeolite membranes. Recently, some novel characterization techniques have been applied. Infrared reflectance measurement was used to characterize membrane thickness [19]. Fluorescence confocal optical microscopy was used to image the grain boundary structure of zeolite membranes [20]. FTIR-ATR method was used to characterize the T-O vibration of zeolite membranes [21],... 

Fluorescence confocal optical microscopy gives the possibility of observing the polycrystalline network of the zeolite membrane and so the internal defects not observable with SEM analysis ... 

Fluorescence confocal optical microscopy is a powerful tool for the non-destructive analysis of zeolite membranes. The grain boundary network of the zeolite layer can be observed along the thickness of the membranes and so the defects can be clearly visualized (Bonilla et al, 2001). 

PM images bear two-dimensional information, integrating the 3D pattern of optical birefringence over the path of light. To obtain 3D director patterns we may use fluorescent confocal polarizing microscopy (FCPM), which is illustrated in Figure 5.15. - ... 

Various solutions have been proposed for the reduction or elimination of autofluorescence. One way is to chemically suppress the autofluorescence signal with some reagents such as sodium borohydride, glycine or toluidine blue. However, in many cases, these approaches are either infeasible or ineffective, and none of them fully eliminates the problem. The second way is to use spectral unmixing algorithms subtracting the background fluorescence. This is only possible if you have at your disposal complicated, expensive confocal optics with sophisticated automated software (http //www.cri-inc.com/applications/fluorescence-microscopy.asp). 

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). 

Fig. 6 Adsorption of microcapsules onto the (PLL/HA)24/PLL films, (a-c) Confocal fluorescent microscopy images of the capsules exposed to the near-IR light irradiation, (d) CLSM image of the film surface (the film is prepared with PLL-FITC black lines are scratches made by a needle for easier film imaging), (e) Cross-sectional profile of the capsules after step-by-step laser exposure (the sections from top to bottom correspond to the images a-c, respectively), (f) Optical microscopy images of the capsules after light irradiation. Scale bars (a-c, f) 4 pm, (d) 25 pm. Reproduced from [100]...

Optical Microscopy. Optical microscopy involves the use of transmitted light, reflected light, polarized light, fluorescence, and more recently, techniques such as confocal microscopy. Each of these variations has particular strengths and applicability. 

We have performed super-resolution infrared microscopy by combining a laser fluorescence microscope with picosecond time-resolved TFD-IR spectroscopy. In this chapter, we have demonstrated that the spatial resolution of the infrared microscope improved to more than twice the diffraction limit of IR light. It should he relatively straightforward to improve the spatial resolution to less than 1 pm by building a confocal optical system. Thus, in the near future, the spatial resolution of our infrared microscope will be improved to a sub-micron scale. 

The last two decades have seen tremendous progress in optical microscopy, especially, confocal fluorescence microscopy. Confocal laser-scanning fluorescence... 

On the other hand, optical microscopy, confocal microscopy, ellipsometry, scanning electron microscopy (SEM), scanning tunneling microscopy (STM), atomic force microscopy (AFM) and total internal reflection fluorescence (TIRF) are the main microscopic methods for imaging the surface structure. There are many good books and reviews on spectroscopic and chemical surface analysis methods and microscopy of surfaces description of the principles and application details of these advanced instrumental methods is beyond the scope of this book. 

Within the last years, single-molecule fluorescence imaging became possible at room temperature and ambient conditions, first with the use of scanning near-field optical microscopy and ultra-high spatial optical resolution (about 100 nm), and later with the use of diffraction limited microscopy techniques (resolution about 300 nm) such as the epi-fluorescence microscopy, internal reflection microscopy, and scanning confocal microscopy. 

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