Image scanning fluorescence

Wokosin D L and White J G 1997 Optimization of the design of a multiple-photon excitation laser scanning fluorescence imaging system Proc. SPIE 2984 25-9... 

After the hybridization process, intensity signals from the hybridized RNA/cDNA samples are usually detected by phospho-imaging or fluorescence scanning and independent images are generated. 

Multi-spectral imaging and linear unmixing add a whole new dimension to laser scanning fluorescence microscopy. Biotechniques 31, 1272-8. 

Based on the qualitative and quantitative analyses of a two-dimensional fluorescent image scan using a low laser power, areas within the field can be chosen for rescanning at a higher killing laser power. This results in the selective cell death of those cells that meet a specific fluorescence-labeling criteria, i.e., selecting for those cells that are either above or below a certain fluorescence-intensity threshold value (see Fig. 5). 

Fig. 6. Schematic diagram of the steps involved in the cookie cutter method of cell selection. (A) Cells are grown on plastic Petri dishes covered with a darkened nylon film. (B) Based on fluorescence intensity image scans using a stage-scanning laser microscope, rare event cells are identified, and octagonal welds are made around those cells to fuse the film to the dish. (C) The film is then peeled away from the dish. (D) The cookies containing the desired cells remain on the dish so that the cells may be analyzed further or subsequently cloned.

Other methods of imaging fat crystals and fat crystal networks (not all of them optical) include confocal laser scanning fluorescence microscopy, multiple photon microscopy, atomic force microscopy and electron microscopy (Narine and Marangoni, 1999). 

In recent years, many other techniques have been employed to elucidate the structure of fat crystal networks including confocal laser scanning fluorescence microscopy (Heertje et al. 1987) and multiple photon microscopy (Marangoni and Hartel 1996). Another advance has been the development of three-dimensional imaging. 

Figure 2. Confocal laser scanning microscopic image (A) fluorescence of pectin, (B) fluorescence of soybean flour protein, (C) fluorescence spectra of pectin and soybean flour protein, and (D) reflection of poly(ethylene oxide). Field width A, B and D, 480 pm.

Figure 19. Correlated images of the same sample observed using cryogenic SEM (left) and scanning laser confocal light microscopy (right). The confocal image in fluorescent mode (right) shows a concentration of fluorescing components that correlates with the clay structure.

V. Ulrich, P. Fischer, I. Riemann, K. Konig, Compact multiphoton / single photon laser scanning microscope for spectral imaging and fluorescence lifetime imaging. Scanning 26, 217-225 (2004)... 

Figure 1.1 Confocal laser scan fluorescence images of single crystals of (a, b)...

Fluorescence microscopy has also been employed largely for 2D surface imaging. Scanning confocal fluorescence microscopy has been applied to the investigation of subsurface morphology of foams. The general knowledge on the applications of fluorescence microscopy for polymers is rather limited. 

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