title: Magnetic single-walled carbon nanotubes-dispersive solid-phase extraction method combined with liquid chromatography-tandem mass spectrometry for the determination of paraquat in urine.
abstract: In this study, magnetic single-walled carbon nanotubes (MSWCNTs) were prepared by impregnating magnetic Fe3O4 nanoparticles onto the surfaces of carboxylic single-walled carbon nanotubes based on electrostatic interactions. The prepared MSWCNTs were used as the adsorbent for the dispersive solid-phase extraction (DSPE) of paraquat from human urine. After adsorption, the paraquat was quantitatively desorbed with 5%TFA in acetonitrile and determined by HPLC-MS. Extraction parameters such as the type of CNT adsorbent, extraction time, sample volume, wash solvent, and the type and volume of desorption solvent were optimized to obtain high DSPE recoveries and extraction efficiencies. Under the optimized conditions, the calibration curve was linear in the range 3.75-375.0 μg/L with a correlation coefficient of 0.999 45. The LOD (S/N=3) and LOQ (S/N=10) were 0.94 and 2.82 μg/L, respectively. The recoveries ranged from 92.89 to 108.9% for spiked real urine samples with RSDs below 3.21%. Finally, the new method was successfully used to determine paraquat in urine samples of suspected paraquat poisoning patients. The MSWCNTs exhibited suitable properties and a high adsorption capacity for the extraction of paraquat.
authors.affiliation: Guangdong Province Hospital for Occupational Disease Prevention and Treatment, Guangdong Provincial Key Laboratory of Occupational Disease Prevention and Treatment, Guangzhou, Guangdong 510300, China. Electronic address: yuetangxl@163.com.
authors.forename: Xiao-Lin
authors.initials: XL
authors.lastname: Ruan
authors.affiliation: Guangdong Province Hospital for Occupational Disease Prevention and Treatment, Guangdong Provincial Key Laboratory of Occupational Disease Prevention and Treatment, Guangzhou, Guangdong 510300, China.
authors.forename: Jing-Jing
authors.initials: JJ
authors.lastname: Qiu
authors.affiliation: Guangdong Province Hospital for Occupational Disease Prevention and Treatment, Guangdong Provincial Key Laboratory of Occupational Disease Prevention and Treatment, Guangzhou, Guangdong 510300, China.
authors.forename: Chuan
authors.initials: C
authors.lastname: Wu
authors.affiliation: Guangdong Province Hospital for Occupational Disease Prevention and Treatment, Guangdong Provincial Key Laboratory of Occupational Disease Prevention and Treatment, Guangzhou, Guangdong 510300, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Huang
authors.affiliation: Guangdong Province Hospital for Occupational Disease Prevention and Treatment, Guangdong Provincial Key Laboratory of Occupational Disease Prevention and Treatment, Guangzhou, Guangdong 510300, China.
authors.forename: Rui-Bo
authors.initials: RB
authors.lastname: Meng
authors.affiliation: Guangdong Pharmaceutical University, Guangzhou, Guangdong 510315, China.
authors.forename: Yong-Qiang
authors.initials: YQ
authors.lastname: Lai
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D006801:Humans; D057230:Limit of Detection; D016014:Linear Models; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010269:Paraquat / Q000737:chemistry / Q000302:isolation & purification / Q000506:poisoning / Q000652:urine*; D015203:Reproducibility of Results; D052616:Solid Phase Extraction / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods
chemical_list: D058185:Magnetite Nanoparticles; D037742:Nanotubes, Carbon; D010269:Paraquat
keywords: Determination; Dispersive solid-phase extraction; HP LC-MS; Magnetic single-walled carbon nanotubes; Paraquat