Sa. Pergantis et al., SPECIATION OF ARSENIC ANIMAL FEED ADDITIVES BY MICROBORE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY, Analyst, 122(10), 1997, pp. 1063-1068
Phenylarsonic compounds have been used as poultry and swine feed addit
ives for the purpose of growth promotion and disease prevention, Owing
to the lack of suitable analytical methods, however, knowledge of the
ir metabolism, environmental fate and impact remains incomplete, In or
der to compensate for this, analytical procedures were developed that
allow the speciation of arsenic animal feed additives by using microbo
re high-performance liquid chromatography (mu HPLC) coupled on-line wi
th ICP-MS, More specifically, reversed-phase (RP) chromatographic meth
ods were optimised to achieve the separation of various phenylarsonic
acids from each other and from the more toxic inorganic arsenic compou
nds, This mode of chromatography, however, exhibits limitations, espec
ially in the presence of naturally occurring organoarsenic compounds,
The application of RP ion-pairing chromatography eliminates such short
comings by minimising the co-elution of arsenic species, In general, t
he mu HPLC-ICP-MS methods developed in this study provide high selecti
vity, extremely good sensitivity, low limits of detection (low-ppb or
sub-pg amounts of As), require small sample volumes (<1 mu l), minimis
e waste and operate most efficiently under low mobile-phase flow rates
(15-40 mu l min(-1)), which are compatible for use with other types o
f mass spectrometers, e.g., electrospray, Reference materials containi
ng naturally occurring arsenic compounds were spiked with phenylarsoni
c compounds and then analysed by using the procedures developed in thi
s study.