Simple Absorbance and Fluorometric Detectors Using Light-Emitting Diodes as Light Source

Tutorial Review

Abstract

Light-emitting diode (LED) is an attractive light source for the simple absorbance or fluorometric detector of flow injection analysis (FIA). Although such detectors are quite simple compared to the conventional ones using a monochromator, some considerations for the design of its circuitry and the use of proper components are necessary in order to attain stable operation and reasonable performance required by FIA. In this article, we described the basic points necessary to build an LED-based detector, emphasizing on aspects of electronic circuits.