Carbon fibers as green and sustainable sorbent for the extraction of isoflavones from environmental waters

Juan L Benedé; Alberto Chisvert; Rafael Lucena; Soledad Cárdenas

doi:10.1016/j.talanta.2021.122582

Carbon fibers as green and sustainable sorbent for the extraction of isoflavones from environmental waters

Talanta. 2021 Oct 1:233:122582. doi: 10.1016/j.talanta.2021.122582. Epub 2021 Jun 5.

Authors

Juan L Benedé¹, Alberto Chisvert², Rafael Lucena³, Soledad Cárdenas⁴

Affiliations

¹ Affordable and Sustainable Sample Preparation (AS2P) Research Group, Departamento de Química Analítica, Instituto Universitario de Investigación en Química Fina y Nanoquímica IUNAN, Universidad de Córdoba, Campus de Rabanales, Edificio Marie Curie (anexo), E-14071, Córdoba, Spain; GICAPC Research Group, Department of Analytical Chemistry, University of Valencia, 46100, Burjassot, Valencia, Spain. Electronic address: benede@uv.es.
² GICAPC Research Group, Department of Analytical Chemistry, University of Valencia, 46100, Burjassot, Valencia, Spain.
³ Affordable and Sustainable Sample Preparation (AS2P) Research Group, Departamento de Química Analítica, Instituto Universitario de Investigación en Química Fina y Nanoquímica IUNAN, Universidad de Córdoba, Campus de Rabanales, Edificio Marie Curie (anexo), E-14071, Córdoba, Spain.
⁴ Affordable and Sustainable Sample Preparation (AS2P) Research Group, Departamento de Química Analítica, Instituto Universitario de Investigación en Química Fina y Nanoquímica IUNAN, Universidad de Córdoba, Campus de Rabanales, Edificio Marie Curie (anexo), E-14071, Córdoba, Spain. Electronic address: scardenas@uco.es.

PMID: 34215074
DOI: 10.1016/j.talanta.2021.122582

Abstract

Isoflavones are a group of phytoestrogens of important environmental concern due to their endocrine disrupting effects. This article presents a rapid, green, and sustainable method for determining four isoflavones (daidzein, genistein, formononetin, and biochanin A) in environmental waters complying with current trends in Analytical Chemistry. The method consists of in-syringe dispersive solid-phase extraction (DSPE) as the extraction approach, using carbon fibers as extraction material. The synthesis of carbon fibers is simple and sustainable, since it only requires a natural product such as raw cotton as precursor, which is thermally treated (600 °C for 30 min) in an inert (Ar) atmosphere to convert it into carbon fibers. After extraction, the final eluate is analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The proposed methodology allows the determination of the four isoflavones in water samples at the ng L^-1 range, with limits of detection in the range from 17 to 25 ng L^-1, relative standard deviations (RSD) from 2.8 to 10.1%, and good batch-to-batch repeatability (RSD < 13%). The method was finally applied to six environmental water samples from different sources and two swimming pool waters, and concentrations of all analytes up to 490 ng L^-1 were found. The highest concentrations were found in those samples close to crop fields. Relative recovery values (80-121%) showed that the aqueous matrices considered in this work did not significantly affect the extraction process. This method overcomes the drawbacks of the previous works with the same purpose, such as consuming large volumes of organic solvents or prolonged extraction times. Moreover, this procedure would allow the extraction stage to be carried out in situ, since only the sorbent material (previously synthesized in the laboratory) and disposable syringes are required.

Keywords: Carbon fibers; Environmental analysis; In-syringe dispersive solid phase extraction; Isoflavones; Phytoestrogens; Surface waters.

MeSH terms

Carbon Fiber
Chromatography, Liquid
Isoflavones* / analysis
Solid Phase Extraction
Tandem Mass Spectrometry
Water Pollutants, Chemical* / analysis

Substances

Carbon Fiber
Isoflavones
Water Pollutants, Chemical