Resolution light microscopy

Ohulchanskyy TY, Roy I, Yong KT, Pudavar HE, Prasad PN (2014) High-resolution light microscopy using luminescent nanoparticles. Wiley Intindiscip Rev Nanomed Nanobiotechnol 2 162-175... 

It is interesting to note the analogy of developments in light microscopy during the last few decades. The confocal microscope as a scaiming beam microscope exceeds by far the nomial fluorescence light microscope in resolution and detection level. Very recent advances in evanescent wave and interference microscopy seem to promise to provide even higher resolution (B1.18). 

Light microscopy is of great importance for basic research, analysis in materials science and for the practical control of fabrication steps. Wlien used conventionally it serves to reveal structures of objects which are otherwise mvisible to the eye or magnifying glass, such as micrometre-sized structures of microelectronic devices on silicon wafers. The lateral resolution of the teclmique is detennined by the wavelength of tire light... 

With a resolution of 0.01 qm this technique outperforms optical light microscopy (0.1 pm) and is used, e.g., to examine fine particles such as metal fume. When linked to other facilities such as dispersive X-ray analysis, quantitative data can be obtained. 

Heintzmann, R. and Ficz, G. (2007). Breaking the resolution limit in light microscopy. Briefings Funct. Genom. Proteom. 5, 289-301. 

Limitations OCT method has relatively insufficient spatial resolution in comparison with light microscopy. 

The structure (e.g., number, size, distribution) of fat crystals is difficult to analyze by common microscopy techniques (i.e., electron, polarized light), due to their dense and interconnected microstructure. Images of the internal structures of lipid-based foods can only be obtained by special manipulation of the sample. However, formation of thin sections (polarized light microscopy) or fractured planes (electron microscopy) still typically does not provide adequate resolution of the crystalline phase. Confocal laserscanning microscopy (CLSM), which is based on the detection of fluorescence produced by a dye system when a sample is illuminated with a krypton/argon mixed-gas laser, overcomes these problems. Bulk specimens can be used with CLSM to obtain high-resolution images of lipid crystalline structure in intricate detail. 

All the imaging modes of light microscopy are amenable to handsectioning methods but none more so than epifluorescence. This is shown clearly by the work of Fulcher and later by that of Yiu [26]. A range of products is examined in these papers, from cereal seeds to cheese and yet the resolution obtained approaches that of sections from embedded product. 

Lamatsch, D.K., Sharbel, T.F., Martin, R. and Bock, C. (1998) A drop technique for flatworm chromosome preparation for light microscopy and high-resolution scanning electron microscopy. Chromosome Research 6, 654-656. 

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