1986 Volume 24 Issue 1 Pages 23-40
An analytical method for water-soluble trivalent and hexavalent chro-mium [Cr(III) and Cr(VI)] was developed using fast protein liquid chromatography equipped with an anion exchange column (FPLC system). The system allowed rapid separation of Cr(III) as an EDTA chelate and Cr(VI) from water extracts of chromium fume particles. The elution times of these chromium species were several minutes or less. Both species in the eluates were determined by UV (275-230 nm) absorption and Cr(VI) also by VIS (370 nm) absorption. The detection limit of Cr(III) was 7 ng and that of Cr(VI) was 2 ng. The average chromium recoveries examined by atomic absorption spectrophotometry (AAS) ranged from 97% to 107% for both species.
The FPLC system was also applied to the investigation of chromium forms in a culture medium (Eagle's minimum essential medium with L-glutamine and fetal calf serum) treated with Cr(III) or/and Cr(VI). The eluates were analyzed for both chromium species by AAS and for Cr(VI) only by the VIS method. Cr(III) was recovered in three fractions involving newly formed complexes with some of the medium components. One of them was shown to be Cr(III)-albumin complex. Cr(VI) was recovered in a single peak separated from these Cr(III) complexes. No reduction of Cr(VI) to the trivalent state was observed.
These results indicate that the FPLC method is applicable to the determination of water-soluble trivalent and hexavalent chromium species in both nonbiological and biological samples.
