Dynamic Background Correction by Wavelength Modulation in ICP Atomic Emission Spectrometry (AES) and its Application to Flow-Injection-ICP-AES

Abstract

This paper describes a fast background correction system based on wavelength modulation that can be adapted to any dispersive ICP spectrometer. It consists of a quartz refractor plate which oscillates just behind the entrance slit to perform rapid wavelength scanning across the emission line. The system inertia is small and allows a fast scan rate, which permits real-time background measurement during fast transient signals. It has been successfully applied to flow-injection-ICP-atomic emission analysis (FIA-ICP-AES). A simple and inexpensive interface is presented to perform wavelength modulation control and data acquisition by an IBM-XT microcomputer. Different mathematical approaches are compared to handle the spectral line intensity, as well as the FIA-AES peaks. The result is a simplified and fast data treatment which can be easily handled by any small microcomputer.