Graphene oxide/Fe3O4 as sorbent for magnetic solid-phase extraction coupled with liquid chromatography to determine 2,4,6-trinitrotoluene in water samples

Abstract

A fast, simple, economical, and environmentally friendly magnetic solidphase extraction (MSPE) procedure has been developed to preconcentrate 2,4,6-trinitrotoluene (TNT) from water samples prior to determination by liquid chromatography-UV-Vis employing graphene oxide/Fe O nanocomposite as sorbent. The nanocomposite synthesis was investigated, and the MSPE was optimized by a multivariate approach. The optimum MSPE conditions were: 40 mg of nanocomposite, 10 min of vortex extraction, 1 mL of acetonitrile as eluent, and 6 min of desorption in an ultrasonic bath. Under the optimized experimental conditions, the method was evaluated obtaining a preconcentration factor of 153. The linearity of the method was studied from 1 to 100 µg L (N!=!5), obtaining a correlation coefficient of 0.994. The relative standard deviation and limit of detection This is a previous version of the article published in Analytical and Bioanalytical Chemistry. 2017, 409(10): 2665-2674. doi:10.1007 were found to be 12% (n!=!6, 10 µg L ) and 0.3 µg L , respectively. The applicability of the method was investigated, analyzing three types of water samples (i.e., reservoir and drinking water and effluent wastewater) and recovery values ranged between 87 and 120% (50 µg L spiking level) showing that the matrix had a negligible effect upon extraction. Finally, the semiquantitative Eco-Scale metrics confirmed the greenness of the developed method.

Determination of siloxanes in water samples employing graphene oxide/Fe3O4 nanocomposite as sorbent for magnetic solid‐phase extraction prior to GC–MS

“…Previous nanocomposite characterization studies by X‐ray photoelectron spectroscopy confirmed the chemical composition. TEM characterized the morphology of GO/Fe 3 O 4 nanocomposite.…”

Graphene-based materials as solid phase extraction sorbent for chromium(VI) determination in red wine

“…Notably, graphene is usually considered to be non-polar and hydrophobic. Graphene oxide (GO), in contrast, contains much more polar moieties, such as hydroxy, expoxy, and carboxy groups, and thus has a more polar and hydrophilic character than graphene [37][38][39][40].…”

Magnetic Solid-Phase Extraction of Organic Compounds Based on Graphene Oxide Nanocomposites

“…Graphene oxide is dispersed in deionized water in order to generate a negatively charged surface. Subsequently, the dispersions of Fe 3 O 4 and GO are mixed, the pH of the mixture is adjusted to a desired value and the mixture is subjected to vigorous magnetic stirring, mechanical shaking or ultrasonic radiation for a certain time span (e.g., 5 h) [41]. Finally, the GO/Fe 3 O 4 material can be prepared after hydroxylation of Fe 3 O 4 nanoparticles by mixing with GO and dimethyl sulfoxide.…”

“…The GO/Fe 3 O 4 magnetic nanocomposite has been employed for the extraction of 2,4,4 -trichlorobiphenyl (PCB 28) [34] and atrazine [48] from water samples prior to their determination by gas chromatography-mass spectrometry (GC-MS). Furthermore, di-2-ethylhexyl phthalate (DEHP) [49], polycyclic aromatic hydrocarbons (PAHs) [32], 2,4,6-trinitrotoluene (TNT) [41], malachite green and crystal violet [50], the cytostatic drugs imatinib and doxorubicin [51] as well as sulfonamides [52] have been extracted from water samples prior to their separation with HPLC and determination using a UV or DAD detector. Figure Reproduced with permission from [57].…”