Vesicular Hydride Generation–In Situ Preconcentration–Electrothermal Atomic Absorption Spectrometry Determination of Sub-parts-per-billion Levels of Cadmium

(Note: The full text of this document is currently only available in the PDF Version )

Heidi Goenaga Infante, María L. Fernández Sánchez and Alfredo Sanz-medel


Abstract

Studies to increase the sensitivity of cadmium determination by atomic absorption spectrometry using continuous hydride generation from a vesicular medium within situ preconcentration in a graphite tube are described. Parameters influencing the efficiency of the continuous generation and transport of cadmium hydride are studied in detail using a Pd-coated graphite platform for in situ preconcentration. Continuous stirring of the sample solutions enhanced, approximately ten-fold, the determination of cadmium. The detection limit (LOD) observed for Cd was 5 ng l–1 when preconcentrating 1.4 ml of sample. Improved LOD can be achieved by preconcentrating larger volumes of sample solution, limited only by a maximum deposition of 0.2 ng Cd on to the platform. The observed relative standard deviation for ten replicate analyses of 0.14 ng of total Cd (1.4 ml of a 100 ng l–1 solution) was excellent (±1.1%). The use of W- and Zr-coated platforms and uncoated graphite tubes for preconcentrating Cd in situ was compared with the Pd-coated platform procedure described. The proposed method has been applied successfully to the determination of ng l–1 levels of this toxic metal in river water and tea infusions.


References

  1. K. Robards and P. Worsfold, Analyst, 1991, 116, 549 RSC.
  2. H. Goenaga Infante, M. L. Fernández Sanchez and A. Sanz-Medel, J. Anal. At. Spectrom., 1996, 11, 571 RSC.
  3. A. Sanz-Medel, M. C. Valdés-Hevia, N. Bordel and M. R. Fernández, Anal. Chem., 1995, 67, 2216 CrossRef CAS.
  4. R. E. Sturgeon, S. N. Willie, G. I. Sproule, P. T. Robinson and S. S. Berman, Spectrochim. Acta, Part B, 1989, 44, 667 CrossRef.
  5. H. Matusiewicz and R. E. Sturgeon, Spectrochim. Acta, Part B, 1996, 51, 377 CrossRef.
  6. J. E. Teague-Nishimura and T. Tominaga, Anal. Chem., 1987, 59, 1651.
  7. R. E. Sturgeon, S. N. Willie, G. I. Sproule and S. S. Berman, J. Anal. At. Spectrom., 1987, 2, 719 RSC.
  8. M. Grotti and A. Mazzucotelli, J. Anal. At. Spectrom., 1995, 10, 325 RSC.
  9. M. M. Chaudhry, A. M. Ure, B. G. Cooksey and D. Littlejohn, Anal. Proc. (London), 1991, 28, 44 Search PubMed.
  10. G. Tao and Z. Fang, J. Anal. At. Spectrom., 1993, 8, 577 RSC.
  11. L. Zhang, Z.-M. Ni and X.-Q. Shan, Spectrochim. Acta, Part B, 1989, 44, 339 CrossRef.
  12. Y. Liao and A. Li, J. Anal. At. Spectrom., 1993, 8, 633 RSC.
  13. Z.-M. Ni, B. He and H.-B. Han, J. Anal. At. Spectrom., 1993, 8, 995 RSC.
  14. P. S. Doidge, B. T. Sturman and T. M. Rettberg, J. Anal. At. Spectrom., 1989, 4, 251 RSC.
  15. X.-P. Yan and Z.-M. Ni, J. Anal. At. Spectrom., 1991, 6, 483 RSC.
  16. D. L. Tsalev, A. D'Ulivo, L. Lampugnani, M. Di Marco and R. Zamboni, J. Anal. At. Spectrom., 1995, 10, 1003 RSC.
  17. S. Garbós, M. Walcerz, E. Bulska and A. Hulanicki, Spectrochim. Acta, Part B, 1995, 50, 1669 CrossRef.
  18. P. Bermejo-Barrera, J. Moreda-Piñeiro, A. Moreda-Piñeiro and A. Bermejo-Barrera, J. Anal. At. Spectrom., 1996, 11, 1081 RSC.
  19. H. J. Gitelman and F. R. Alderman, J. Anal. At. Spectrom., 1990, 5, 687 RSC.
  20. M. C. Valdés-Hevia y Temprano, M. R. Fernández de la Campa and A. Sanz-Medel, J. Anal. At. Spectrom., 1993, 8, 847 RSC.
  21. A. Sanz-Medel, M. C. Valdés-Hevia y Temprano, N. Bordel García and M. R. Fernández de la Campa, Anal. Proc. (London), 1995, 32, 49 Search PubMed.
  22. D. C. Grégoire and J. Lee, J. Anal. At. Spectrom., 1994, 9, 393 RSC.
  23. G. Chapple and J. P. Byrne, J. Anal. At. Spectrom., 1996, 11, 549 RSC.
Click here to see how this site uses Cookies. View our privacy policy here.