title: Direct amino acid analysis method for speciation of selenoamino acids using high-performance anion-exchange chromatography coupled with integrated pulsed amperometric detection.
abstract: Speciation analysis of selenomethylcysteine (SeMeCys), selenomethionine (SeMet) and selenocystine (SeCys) has been performed using a direct amino acid analysis method with high-performance anion-exchange chromatography (HPAEC) coupled with integrated pulsed amperometric detection (IPAD). Three selenoamino acids could be baseline-separated from 19 amino acids using gradient elution conditions for amino acids and determined under new six-potential waveform. Detection limits for SeMeCys, SeMet and SeCys were 0.25, 1 and 20 microg/L (25 microL injection, 10 times of the baseline noise), respectively. The relative standard deviations (RSDs) of 200 microg/L SeMeCys, SeMet and SeCys were 3.1, 4.1 and 2.8%, respectively (n=9, 25 microL injection). The proposed method has been applied for determination of selenoamino acids in extracts of garlic and selenious yeast granule samples. No selenoamino acids were found in garlic. Both SeMet and SeCys were detected in selenious yeast tablet with the content of 45 and 129 microg Se/g, respectively. Selenoamino acids standards were spiked in garlic and yeast granule samples and the recovery ranged from 90 to 106%.
authors.affiliation: State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085, China.
authors.forename: Lina
authors.initials: L
authors.lastname: Liang
authors.forename: Shumin
authors.initials: S
authors.lastname: Mo
authors.forename: Yaqi
authors.initials: Y
authors.lastname: Cai
authors.forename: Shifen
authors.initials: S
authors.lastname: Mou
authors.forename: Guibin
authors.initials: G
authors.lastname: Jiang
authors.forename: Meijuan
authors.initials: M
authors.lastname: Wen
mesh_terms: D000596:Amino Acids / Q000032:analysis* / Q000302:isolation & purification; D000837:Anion Exchange Resins / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D003553:Cystine / Q000031:analogs & derivatives / Q000032:analysis / Q000302:isolation & purification; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods*; D005737:Garlic / Q000737:chemistry; D016566:Organoselenium Compounds / Q000032:analysis / Q000302:isolation & purification; D015203:Reproducibility of Results; D012645:Selenomethionine / Q000032:analysis / Q000302:isolation & purification; D015003:Yeasts / Q000737:chemistry
chemical_list: D000596:Amino Acids; D000837:Anion Exchange Resins; D016566:Organoselenium Compounds; C009226:selenocystine; D003553:Cystine; D012645:Selenomethionine