A microcomputer-controlled background correction system for atomic spectrometry

Abstract

A novel instrument system has been designed for use in atomic spectrometry. An Apple microcomputer is used to control data acquisition and perform data processing in a single-channel spectrometer system, which may be applied to continuum-source atomic-absorption or atomic-emission measurement. Wavelength modulation, a rapid, repetitive scanning procedure, is employed to perform automatic background correction under computer control. The microcomputer programs are written in BASIC with incorporated assembly language subroutines. The system may be used in a steady-state atomisation mode (e.g., flames) or in a transient atomisation mode (e.g., electrothermal atomisers) for either absorption or emission measurement. The microcomputer program provides peak-height and peak-area data simultaneously and a procedure is available that allows the extension of the linear calibration range. Detection limits obtained using the system are comparable to previously reported values. The software organisation and operating procedures are described and illustrated using typical output signals measured by the system.