title: Determination of nine sensitizing disperse dyes in activated sludge by ultrasound-assisted liquid-liquid extraction-ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry.
abstract: A method was developed on the basis of ultrasound-assisted liquid-liquid extraction ultra-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (ULLE-UPLC-ESI-MS/MS) to determine nine sensitizing disperse dyes in activated sludge. The samples were extracted using ULLE and separated through UPLC on an ACQUITY UPLCTM BEH C18 column with a gradient elution program of acetonitrile and acidified water (containing 2% acetonitrile, 0.2% formic acid, and 0.005 mol/L ammonium; pH 2.7) as the mobile phase. The samples were then identified and quantified through UPLC-ESI-MS/MS in a positive mode and multiple reaction monitoring. Results showed good linearity (10-1000 μg/L, 0.9934-0.9998), detection limit (0.08-2.17 μg/L), and quantification limit (0.27-7.38 μg/L) for the nine sensitizing disperse dyes, with recoveries ranging from 65.0 to 111.3%. The proposed method was applied to detect and determine the concentration of sensitizing disperse dyes in sludge samples obtained from various sewage treatment plants (six dyeing enterprises and one dye manufacturer). Three sensitizing disperse dyes were identified, and the lowest concentration detected was 10 μg/kg.
authors.affiliation: Key Lab of Pesticide Environmental Assessment and Pollution Control, Nanjing Institute of Environment Sciences, Ministry of Environment Protection (MEP), Nanjing, 210042, China.|Nanjing Technology University, Nanjing, 210009, China.
authors.forename: Linjun
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Key Lab of Pesticide Environmental Assessment and Pollution Control, Nanjing Institute of Environment Sciences, Ministry of Environment Protection (MEP), Nanjing, 210042, China.
authors.forename: Lili
authors.initials: L
authors.lastname: Shi
authors.affiliation: Key Lab of Pesticide Environmental Assessment and Pollution Control, Nanjing Institute of Environment Sciences, Ministry of Environment Protection (MEP), Nanjing, 210042, China. ljn@nies.org.
authors.forename: Jining
authors.initials: J
authors.lastname: Liu
authors.affiliation: Nanjing Technology University, Nanjing, 210009, China.
authors.forename: Fenglan
authors.initials: F
authors.lastname: Lv
authors.affiliation: Nanjing Technology University, Nanjing, 210009, China. xuyh@njtech.edu.cn.
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Xu
keywords: Activated sludge; Liquid chromatography–mass spectrometry; Sensitizing disperse dye; Ultrasound-assisted liquid–liquid extraction