Bioimaging luminescence microscopy

An example of the utility of the time-resolved technique in eliminating the interference from background fluorescence in bioimaging is shown in Figure 13.17b. Nagano and coworkers compared time-resolved luminescence microscopy with conventional microscopy using live cultured HeLa cells injected with a Eu + complex Eu-36 (or Eu-37). In the prompt fluorescence images, both the luminescence of Eu-36 (or Eu-37) and weak autofluorescence from... 

Multiphoton or two-photon laser scanning microscopy is an alternative to confocal and time-resolved microscopy for bioimaging applications. The principle has been discussed in Lanthanides Luminescence Applications and concerns a two-photon excitation from the simultaneous absorption of two photons in a single quantized event. A bioprobe that normally absorbs ultraviolet light (Xex = 350 nm) can also be excited by two photons of NIR light, at 700 nm (the wavelength is twice that required for one-photon excitation). These two photons must interact simultaneously, which means in a very small lapse time. The instrumentation requires pulse lasers to provide sufficient power, as the photon density must... 

The first two chapters of this work cover theoretical and practical aspects of the emission process, the spectroscopic techniques and the equipment used to characterize the emission. Chapter 3 introduces and reviews the property of circularly polarized emission, while Chapter 4 reviews the use of lanthanide ion complexes in bioimaging and fluorescence microscopy. Chapter 5 covers the phenomenon of two-photon absorption, its theory as well as applications in imaging, while Chapter 6 reviews the use of lanthanide ions as chemo-sensors. Chapter 7 introduces the basic principles of nanoparticle upconversion luminescence and its use for bioimaging and Chapter 8 reviews direct excitation of the lanthanide ions and the use of the excitation spectra to probe the metal ion s coordination environment in eoordination compounds and biopolymers. Finally, Chapter 9 describes the formation of heterobimetallic complexes, in whieh the lanthanide ion emission is promoted through the hetero-metal. 

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