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Publisher Summary This chapter discusses the laser fluorescence techniques. The development of laser techniques has greatly augmented the analytical applications of fluorescence techniques. The most notable change has been to extend the limits of detection, usually by several orders of magnitude. The time resolution inherent in fluorescence techniques has been greatly increased due to the subnanosecond pulses now available from a variety of laser sources. There are many parameters that characterize a lasers performance: peak power, average power tunability, line width, pulse width, and repetition rate. Line width is generally of little importance when analyzing solutions, while tunability is essential. Pulse width is an important factor in time-resolved studies, but a great deal of very sensitive analytical work has appeared, using pulses, with fall times of several nanoseconds. This chapter describes the experimental apparatus and procedures used in the authors laboratory for the chemical analysis of trace quantities by laser-induced molecular fluorescence. Results are presented for three vitamins, which are: riboflavin and its coenzyme flavin adenine dinucleotide (FAD), pyridoxine, and vitamin A; tryptophan; and, fluorescently labeled, arginine. |
