TY - JOUR
T1 - Speciation of inorganic selenium in environmental samples after suspended dispersive solid phase microextraction combined with inductively coupled plasma spectrometric determination
AU - Nyaba, Luthando
AU - Matong, Joseph M.
AU - Dimpe, K. Mogolodi
AU - Nomngongo, Philiswa N.
N1 - Publisher Copyright:
© 2016 Elsevier B.V. All rights reserved.
PY - 2016/10/1
Y1 - 2016/10/1
N2 - A rapid and effective suspended dispersive solid phase microextraction (SDSPME) was developed for the speciation of inorganic selenium using alumina nanoparticles functionalized with Aliquat-336. The target analytes were preconcentrated and determined by inductively coupled plasma optical emission spectrometry. Alumina nanoparticles were characterized using XRD, BET, SEM and EDX while the functionalized nano-Al2O3 was characterized by FTIR. The effect of pH of the solution on speciation Se in water samples was optimized separately. It was observed that when the pH values of sample solution ranged from 2.0 to 7.0, successful separation of inorganic Se species was achieved. The percentage recoveries for Se (IV) and Se (VI) were >90% and 5%, respectively. The two-level fractional factorial design was used to optimize experimental parameters affecting the preconcentration system. Under optimal conditions, the enrichment factor (EF), limit of detection (LOD) and limit of quantification for Se (IV) were found to be 850, 1.4 ng L-1, and 4.6 ng L-1, respectively. Furthermore, intra-day and inter-day precisions expressed in terms of relative standard deviation (RSD) were found to be 1.9% and 3.3%, respectively. The effect of coexisting ions on the recovery of Se (IV) was investigated. The accuracy of the developed method was checked by analysis of standard reference material (NIST SRM 1643e). The optimized method was applied for the determination of targets in surface water samples.
AB - A rapid and effective suspended dispersive solid phase microextraction (SDSPME) was developed for the speciation of inorganic selenium using alumina nanoparticles functionalized with Aliquat-336. The target analytes were preconcentrated and determined by inductively coupled plasma optical emission spectrometry. Alumina nanoparticles were characterized using XRD, BET, SEM and EDX while the functionalized nano-Al2O3 was characterized by FTIR. The effect of pH of the solution on speciation Se in water samples was optimized separately. It was observed that when the pH values of sample solution ranged from 2.0 to 7.0, successful separation of inorganic Se species was achieved. The percentage recoveries for Se (IV) and Se (VI) were >90% and 5%, respectively. The two-level fractional factorial design was used to optimize experimental parameters affecting the preconcentration system. Under optimal conditions, the enrichment factor (EF), limit of detection (LOD) and limit of quantification for Se (IV) were found to be 850, 1.4 ng L-1, and 4.6 ng L-1, respectively. Furthermore, intra-day and inter-day precisions expressed in terms of relative standard deviation (RSD) were found to be 1.9% and 3.3%, respectively. The effect of coexisting ions on the recovery of Se (IV) was investigated. The accuracy of the developed method was checked by analysis of standard reference material (NIST SRM 1643e). The optimized method was applied for the determination of targets in surface water samples.
KW - Preconcentration
KW - River water, dispersive solid phase microextraction
KW - Selenium (IV)
KW - Selenium (VI)
KW - Speciation
UR - http://www.scopus.com/inward/record.url?scp=84975154440&partnerID=8YFLogxK
U2 - 10.1016/j.talanta.2016.06.023
DO - 10.1016/j.talanta.2016.06.023
M3 - Article
AN - SCOPUS:84975154440
SN - 0039-9140
VL - 159
SP - 174
EP - 180
JO - Talanta
JF - Talanta
ER -