Magnetic headspace adsorptive extraction of chlorobenzenes prior to thermal desorption gas chromatography-mass spectrometry

Lorena Vidal; Mazaher Ahmadi; Elena Fernández; Tayyebeh Madrakian; Antonio Canals

doi:10.1016/j.aca.2017.04.002

Magnetic headspace adsorptive extraction of chlorobenzenes prior to thermal desorption gas chromatography-mass spectrometry

Anal Chim Acta. 2017 Jun 8:971:40-47. doi: 10.1016/j.aca.2017.04.002. Epub 2017 Apr 10.

Authors

Lorena Vidal¹, Mazaher Ahmadi², Elena Fernández³, Tayyebeh Madrakian², Antonio Canals⁴

Affiliations

¹ Department of Analytical Chemistry, Nutrition and Food Sciences and University Institute of Materials, University of Alicante, P.O. Box 99, E-03080, Alicante, Spain. Electronic address: lorena.vidal@ua.es.
² Faculty of Chemistry, Bu-Ali Sina University, Hamedan, Iran.
³ Department of Analytical Chemistry, Nutrition and Food Sciences and University Institute of Materials, University of Alicante, P.O. Box 99, E-03080, Alicante, Spain.
⁴ Department of Analytical Chemistry, Nutrition and Food Sciences and University Institute of Materials, University of Alicante, P.O. Box 99, E-03080, Alicante, Spain. Electronic address: a.canals@ua.es.

PMID: 28456282
DOI: 10.1016/j.aca.2017.04.002

Abstract

This study presents a new, user-friendly, cost-effective and portable headspace solid-phase extraction technique based on graphene oxide decorated with iron oxide magnetic nanoparticles as sorbent, located on one end of a small neodymium magnet. Hence, the new headspace solid-phase extraction technique has been called Magnetic Headspace Adsorptive Extraction (Mag-HSAE). In order to assess Mag-HSAE technique applicability to model analytes, some chlorobenzenes were extracted from water samples prior to gas chromatography-mass spectrometry determination. A multivariate approach was employed to optimize the experimental parameters affecting Mag-HSAE. The method was evaluated under optimized extraction conditions (i.e., sample volume, 20 mL; extraction time, 30 min; sorbent amount, 10 mg; stirring speed, 1500 rpm, and ionic strength, non-significant), obtaining a linear response from 0.5 to 100 ng L^-1 for 1,3-DCB, 1,4-DCB, 1,2-DCB, 1,3,5-TCB, 1,2,4-TCB and 1,2,3-TCB; from 0.5 to 75 ng L^-1 for 1,2,4,5-TeCB, and PeCB; and from 1 to 75 ng L^-1 for 1,2,3,4-TeCB. The repeatability of the proposed method was evaluated at 10 ng L^-1 and 50 ng L^-1 spiking levels, and coefficients of variation ranged between 1.5 and 9.5% (n = 5). Limits of detection values were found between 93 and 301 pg L^-1. Finally, tap, mineral and effluent water were selected as real water samples to assess method applicability. Relative recoveries varied between 86 and 110% showing negligible matrix effects.

Keywords: Chlorobenzenes; Gas chromatography-mass spectrometry; Magnetic graphene oxide; Magnetic headspace adsorptive extraction; Solid-phase microextraction; Water samples.