title: Laser-Ablation Sampling for Accurate Analysis of Sulfur in Edible Salts.
abstract: We evaluated the performance of laser ablation analysis techniques such as laser-induced breakdown spectroscopy (LIBS), laser ablation inductively coupled optical emission spectrometry (LA-ICP-OES), and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), in comparison with that of ICP-OES using aqueous solutions for the quantification of sulfur (S) in edible salts from different geographical origins. We found that the laser ablation based sampling techniques were not influenced by loss of S, which was observed in ICP-OES with aqueous solutions for a certain salt upon their dissolution in aqueous solutions, originating from the formation of volatile species and precipitates upon their dilution in water. Although detection of S using direct laser sampling with LA-ICP-MS has well-known isobaric and polyatomic interferences, LIBS and LA-ICP-OES showed good accuracy in the detection of S for all salts. LIBS also provided the ability to identify the dominant chemical form in which S is present in salts. Correlation between S and oxygen, observed in LIBS spectra, provided chemical information about the presence of S2-or [Formula: see text], which are associated with the origin and quality of edible salts.
authors.affiliation: 1 Department of Chemistry, Mokpo National University, Jeonnam, Republic of Korea.
authors.forename: Yonghoon
authors.initials: Y
authors.lastname: Lee
authors.affiliation: 2 Escuela de Química, Facultad de Ciencias, Universidad Central de Venezuela, Venezuela.
authors.forename: Jose
authors.initials: J
authors.lastname: Chirinos
authors.affiliation: 3 Lawrence Berkeley National Laboratory, Berkeley, CA, USA.|4 Applied Spectra, Inc., Fremont, CA, USA.
authors.forename: Jhanis
authors.initials: J
authors.lastname: Gonzalez
authors.affiliation: 3 Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
authors.forename: Dayana
authors.initials: D
authors.lastname: Oropeza
authors.affiliation: 3 Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
authors.forename: Vassilia
authors.initials: V
authors.lastname: Zorba
authors.affiliation: 3 Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
authors.forename: Xianglei
authors.initials: X
authors.lastname: Mao
authors.affiliation: 4 Applied Spectra, Inc., Fremont, CA, USA.
authors.forename: Jonghyun
authors.initials: J
authors.lastname: Yoo
authors.affiliation: 3 Lawrence Berkeley National Laboratory, Berkeley, CA, USA.|4 Applied Spectra, Inc., Fremont, CA, USA.
authors.forename: Richard E
authors.initials: RE
authors.lastname: Russo
keywords: Edible salt; LA-ICP-MS; LA-ICP-OES; LIBS; laser ablation inductively coupled optical emission spectrometry; laser ablation inductively coupled plasma mass spectrometry; laser ablation sampling; laser-induced breakdown spectroscopy; sulfur