Chemical speciation of arsenic was carried out in serum of a total of
51 uraemic patients: 19 non dialysis (ND), 18 haemodialysis (HD) and 1
4 continuous ambulatory peritoneal dialysis (CAPD) patients, The low m
olecular mass As species were separated by ion-exchange liquid chromat
ography and measured on-line by hydride generation atomic absorption s
pectrometry (HGAAS), The high molecular mass As species were separated
by fast protein liquid chromatography, either size-exclusion, ion-exc
hange or affinity chromatography; and the fractions were digested and
measured off-line with HGAAS. The mean total As concentrations in the
serum of the three groups of the uraemic patients were significantly h
igher than the reference value (6.47 +/- 4.28, 5.12 +/- 5.58 and 4.67
+/- 5.41 mu g l(-1) for HD, ND and CAPD patients, respectively, versus
the reference value of 0.96 +/- 1.52 mu g l(-1)), The major As specie
s in serum of the patients were dimethylarsinic acid (DMA) and arsenob
etaine, The HD patients showed a significantly higher mean DMA level t
han ND and CAPD patients, No selective removal of different As species
in serum of HD patients was observed after 4 h of haemodialysis, The
inorganic As species in serum were bound to proteins, mainly transferr
in (about 5-6% of total As in serum), This binding may play an importa
nt role in arsenic detoxification.