title: Selenium speciation using capillary electrophoresis coupled with modified electrothermal atomic absorption spectrometry after selective extraction with 5-sulfosalicylic acid functionalized magnetic nanoparticles.
abstract: A new method for selenium speciation in fermented bean curd wastewater and juice was described. This method involved sample extraction with 5-sulfosalicylic acid (SSA)-functionalized silica-coated magnetic nanoparticles (SMNPs), capillary electrophoresis (CE) separation, and online detection with a modified electrothermal atomic absorption spectrometry (ETAAS) system. The modified interface for ETAAS allowed for the introduction of CE effluent directly through the end of the graphite tube. Elimination of the upper injection hole of the graphite tube reduced the loss of the anlayte and enhanced the detection sensitivity. The SSA-SMNPs were synthesized and used to extract trace amounts of selenite [Se(IV)], selenite [Se(VI)], selenomethionine (SeMet), and selenocystine (SeCys2) from dilute samples. The concentration enrichment factors for Se(VI), Se(IV), SeMet, and SeCys2 were 21, 29, 18, and 12, respectively, using the SSA-SMNPs extraction. The limits of detection for Se(VI), Se(IV), SeMet, and SeCys2 were 0.18, 0.17, 0.54, 0.49ngmL(-1), respectively. The RSD values (n=6) of method for intraday were observed between 0.7% and 2.9%. The RSD values of method for interday were less than 3.5%. The linear range of Se(VI) and Se(IV) were in the range of 0.5-200ngmL(-1), and the linear ranges of SeMet and SeCys2 were 2-500 and 2-1000ngmL(-1), respectively. The detection limits of this method were improved by 10 times due to the enrichment by the SSA-SMNP extraction. The contents of Se(VI) and Se(IV) in fermented bean curd wastewater were measured as 3.83 and 2.62ngmL(-1), respectively. The contents of Se(VI), Se(IV), SeMet, and SeCys2 in fermented bean curd juice were determined as 6.39, 4.08, 2.77, and 4.00ngmL(-1), respectively. The recoveries were in the range of 99.14-104.5% and the RSDs (n=6) of recoveries between 0.82% and 3.5%.
authors: Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China), School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China.
authors: Lizhen
authors: L
authors: Yan
authors: Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China), School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China. Electronic address: dengby16@163.com.
authors: Biyang
authors: B
authors: Deng
authors: Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China), School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China.
authors: Caiying
authors: C
authors: Shen
authors: Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China), School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China.
authors: Chanjuan
authors: C
authors: Long
authors: Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China), School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China.
authors: Qiufen
authors: Q
authors: Deng
authors: Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China), School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China.
authors: Chunyao
authors: C
authors: Tao
mesh_terms: D001557:Benzenesulfonates / Q000737:chemistry*; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D019075:Electrophoresis, Capillary; D057230:Limit of Detection; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D012459:Salicylates / Q000737:chemistry*; D012643:Selenium / Q000737:chemistry* / Q000302:isolation & purification; D012822:Silicon Dioxide / Q000737:chemistry; D013054:Spectrophotometry, Atomic; D062065:Wastewater / Q000737:chemistry
chemical_list: D001557:Benzenesulfonates; D058185:Magnetite Nanoparticles; D012459:Salicylates; D012643:Selenium; D012822:Silicon Dioxide; D062065:Wastewater; C003366:sulfosalicylic acid
keywords: Capillary electrophoresis; Electrothermal atomic absorption spectrometry; Magnetite nanoparticle; Selenium; Speciation analysis