COUPLING TECHNIQUES FOR INDUCTIVELY-COUPLED PLASMA OPTICAL-EMISSION SPECTROMETRY USING AN ARRAY SPECTROMETER FOR LASER SOLID SAMPLING AND SPECIATION

An array spectrometer for inductively coupled plasma optical emission spectrometry (ICP-OES) uses a solid-state detector to register spectra l regions in real time. This makes it an ideal tool for coupling devic es that produce non-steady-state signals, because of the ability to pe rform background correction and, if necessary, internal standardizatio n simultaneously. The important figures of merit for this type of appl ication, such as precision and detection limits versus measuring time and long-term stability were investigated. The precision obtained was below 0.1% when an internal standard with matched excitation condition s was used with pneumatic nebulization. For solid sampling, it ranged to a few per cent,, representing sample inhomogeneity. The long-term s tability was determined continuously with an average maximum deviation of a few per cent. Two model applications, laser solid sampling and h igh-performance liquid chromatography coupled with an ICP-OES instrume nt are presented.