Partial cell irradiation with a tunable organic dye laser.

Abstract

SINCE the laser first became available, it has been applied extensively for partial cell irradiation1–4. The intensity, coherence and monochromaticity of laser light have made it an ideal radiation source for selective alteration of cell organelles. Most of the laser microbeam studies up to the present have utilized a laser device that emits light of either a single or small number of wavelengths. In a few instances it has been possible to increase the spectral output of a laser by using non-linear optics to generate second or third harmonic wavelengths5,6. Ideally, an investigator would like one microbeam system that can deliver wavelengths throughout the entire visible and ultraviolet spectrum. Such a device would permit alteration of a greater variety of organelles and organisms, and it would facilitate derivation of the precise action spectrum of the particular response being studied. This capability would be invaluable for understanding the basic nature of the biological change at the molecular level.