THE FUTURE OF ATOMIC ABSORPTION SPECTROMETRY: A CONTINUUM SOURCE WITH A CHARGE COUPLED ARRAY DETECTOR

Authors: Harnly, James - Jim

Submitted to: Journal of Analytical Atomic Spectrometry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/17/1998
Publication Date: N/A
Citation: Harnly, J.M. 1999. The future of atomic absorption spectrometry: a continuum source with a charge coupled array detector. Journal of Analytical Atomic Spectrometry. 14:137-146.

Interpretive Summary: Atomic absorption spectrometry (AAS) is a powerful tool for the determination of trace metals in complex matrices but is traditionally a single element method. With the use of a continuum source (CS-AAS), multielement determinations can be made but the rest of the instrument must be modified to obtain maximum performance. Array detectors, specifically charge coupled devices, used with high resolution spectrometers provide CS-AAS with operational characteristics that exceed those of conventional AAS. CS-ASS is able to make more accurate absorbance measurements (corrected for spectral interferences), detect lower concentrations, calibrate over a far greater concentration range, and, with proper instrument design, detect 20 to 30 elements simultaneously. Commercialization of CS-AAS will have a considerable impact on all areas of research and industry dependent upon trace metal determinations.

Technical Abstract: Continuum source atomic absorption spectrometry (CS-AAS) has make impressive progress in the last 5 years thanks to the availability of high resolution echelle spectrometers and solid state array detectors. With these new spectrometers and detectors, the capabilities of CS-AAS exceed those of conventional, line source-AAS (LS-ASS). For CS-AAS, absorbances are more accurate (corrected for stray radiation and non-specific broadband background absorption and integrated with respect to height in the furnace), detection limits average a factor of 2 lower, calibration ranges are a factor of 1000 greater, multi- wavelength data are available for correction of spectral interferences, sensitivity is a powerful quality assurance measure since it is independent of all instrument parameters except atomization temperature and, of course, multi-element detection is possible. The future appears bright for CS-AAS. Whereas, previously, CS-AAS was striving for parity with LS-AAS, it is now reasonable to state that it is CS-AAS which is setting the standard.