TY - JOUR
T1 - A micro-wave assisted sequential extraction of water and dilute acid soluble arsemic species from marine plant and animal tissues
AU - Foster, Simon
AU - Maher, Bill
AU - Apte, Simon
PY - 2007
Y1 - 2007
N2 - This paper describes the use of dilute nitric acid for the extraction and quantification of arsenic species. A number of extractants (e.g. water, 1.5 M orthophosphoric acid, methanol–water and dilute nitric acid) were tested for the extraction of arsenic from marine biological samples, such as plants that have proved difficult to quantitatively extract. Dilute 2% (v/v) nitric acid was found to give the highest recoveries of arsenic overall and was chosen for further optimisation. The optimal extraction conditions for arsenic were 2% (v/v) HNO3, 6 min−1, 90 °C. Arsenic species were found to be stable under the optimised conditions with the exception of the arsenoriboses which degraded to a product eluting at the same retention time as glycerol arsenoribose. Good agreement was found between the 2% (v/v) HNO3 extraction and the methanol–water extraction for the certified reference material DORM-2 (AB 17.1 and 16.2 μg g−1, respectively, and TETRA 0.27 and 0.25 μg g−1, respectively), which were in close agreement with the certified concentrations of AB 16.4 ± 1.1 μg g−1 and TETRA 0.248 ± 0.054 μg g−1. To preserve the integrity of arsenic species, a sequential extraction technique was developed where the previously methanol–water extracted pellet was further extracted with 2% (v/v) HNO3 under the optimised conditions. Increases in arsenic recoveries between 13% and 36% were found and speciation of this faction revealed that only inorganic and simple methylated species were extracted
AB - This paper describes the use of dilute nitric acid for the extraction and quantification of arsenic species. A number of extractants (e.g. water, 1.5 M orthophosphoric acid, methanol–water and dilute nitric acid) were tested for the extraction of arsenic from marine biological samples, such as plants that have proved difficult to quantitatively extract. Dilute 2% (v/v) nitric acid was found to give the highest recoveries of arsenic overall and was chosen for further optimisation. The optimal extraction conditions for arsenic were 2% (v/v) HNO3, 6 min−1, 90 °C. Arsenic species were found to be stable under the optimised conditions with the exception of the arsenoriboses which degraded to a product eluting at the same retention time as glycerol arsenoribose. Good agreement was found between the 2% (v/v) HNO3 extraction and the methanol–water extraction for the certified reference material DORM-2 (AB 17.1 and 16.2 μg g−1, respectively, and TETRA 0.27 and 0.25 μg g−1, respectively), which were in close agreement with the certified concentrations of AB 16.4 ± 1.1 μg g−1 and TETRA 0.248 ± 0.054 μg g−1. To preserve the integrity of arsenic species, a sequential extraction technique was developed where the previously methanol–water extracted pellet was further extracted with 2% (v/v) HNO3 under the optimised conditions. Increases in arsenic recoveries between 13% and 36% were found and speciation of this faction revealed that only inorganic and simple methylated species were extracted
U2 - 10.1016/j.talanta.2006.04.027
DO - 10.1016/j.talanta.2006.04.027
M3 - Article
SN - 0039-9140
VL - 71
SP - 537
EP - 549
JO - Talanta
JF - Talanta
IS - 2
ER -