Binding of Al by protein in plasma of patients on maintenance hemodialysis
Cochran, M.; Patterson, D.; Neoh, S.; Stevens, B.; Mazzachi, R.
Clinical Chemistry 31(8): 1314-1316
1985
ISSN/ISBN: 0009-9147 PMID: 3926344 Document Number: 243602
Gel filtration of plasma from hemodialysis patients, with use of reagents and apparatus with carefully minimized background Al concentrations, reproducibly showed a single peak for Al, corresponding exactly to the elution position of transferrin. The Al/transferrin molar ratio in adjacent fractions was constant (mean 0.126, SE 0.006) in replicate experiments. In contrast, the association of Al with albumin varied. Using both equilibrium dialysis and gel-filtration techniques, in the presence and absence of calcium or phosphate, we could demonstrate no significant binding of Al by human albumin at Al concentrations of 1 to 12 mumol/L. We saw no Al peak in pooled, concentrated, low-molecular-mass fractions of plasma gel-filtered on Sephadex G-50. Evidently, transferrin is the sole Al-binding protein in plasma of hemodialysis patients.