We describe the theory and implementation of a frequency-domain fluorescence lifetime confocal microscope using switched diode laser illumination. Standard, communications-type, radio-frequency electronics are used to provide inexpensive modulation references and to perform phase-sensitive detection. This allows the rapid acquisition of fluorescence intensity and lifetime images and their displ...

The ability to modify the character of fluorescent emission by a laser-controlled, optically nonlinear process has recently been shown theoretically feasible, and several possible applications have already been identified. In operation, a pulse of off-resonant probe laser beam, of sufficient intensity, is applied to a system exhibiting fluorescence, during the interval of excited-state decay fo...

Steady state LIF spectra using 488 nm of cw Ar + laser and 355 nm of pulsed Nd:YAG laser, fluorescence induction kinetics using 488 nm laser light were studied in wheat seedlings exposed to increasing cadmium (Cd) concentrations (0.01, 0.1, 1.0 and 2.0 mM). In addition, some growth parameters and pigment content were also measured. The LIF spectra of the leaves exhibited two characteristic band...

The aim of this study was to evaluate the application of quantum dots (QDs) and the FITC labeling technique in Tca8113 cells, and to compare the fluorescence intensity and photostability of these techniques. First, using one-colour confocal microscopy, QDs and FITC were applied separately to tag HSP70 in Tca8113 strains with indirect immunofluorescence. The expression of HSP70 in Tca8113 cells ...

In this chapter, we review the imaging techniques and methods of molecular interrogation made possible by integrating laser light sources with microscopy. We discuss the advantages of exciting fluorescence by laser illumination and review commonly used laser-based imaging techniques such as confocal, multiphoton, and total internal reflection microcopy. We also discuss emerging imaging modaliti...

In this work we present the design and implementation of an experimental facility for the study of the reaction mechanisms of the CCl2 radicals produced in the Infrared Multiple-Photon Dissociation of CDCl3. The design of this facility was performed by combining two techniques: Laser Induced Fluorescence (LIF) and Infrared Multiple-Photon Dissociation (IRMPD). A TEA CO2 laser and a dye laser we...

An approach for simultaneous detection of NO, OH and O in flames using laser-induced fluorescence is presented. The technique is based on spectral coincidences using a Nd:YAG-based laser system producing a frequency-doubled and frequency-mixed laser beam at 287 and 226 nm, respectively. The possibility of making spatially resolved measurements using a diode-array detector was also investigated....

Laser-induced fluorescence measurements of OH have been performed in an atmospheric stoichiometric CH(4)/air flame and in a highly sooting propane flame. The measurements were realized with a single 6-nsec pulse from a frequency-doubled dye laser pumped by a Nd:YAG laser and with a spatial resolution of ~25 microm. This was achieved by imaging through a suitably chosen filter set a section of t...

We use time-resolved imaging to examine the lysis dynamics of non-adherent BAF-3 cells within a microfluidic channel produced by the delivery of single highly-focused 540 ps duration laser pulses at lambda = 532 nm. Time-resolved bright-field images reveal that the delivery of the pulsed laser microbeam results in the formation of a laser-induced plasma followed by shock wave emission and cavit...

This paper describes a simple and efficient approach to reduce the background level of confocal laser induced fluorescence (LIF) detection for round capillaries by laterally shifting the laser focus point. A phenomenon of spontaneous separation of the fluorescence and reflected laser beams at the pinhole of a confocal LIF system when the laser focus point deviates from the center of a capillary...