A nanocomposite consisting of graphene oxide and Fe3O4 magnetic nanoparticles for the extraction of flavonoids from tea, wine and urine samples

Abstract

We describe a single-step solvothermal method for the preparation of nanocomposites consisting of graphene oxide and Fe 3 O 4 nanoparticles (GO/Fe 3 O 4 ). This material is shown to be useful as a magnetic sorbent for the extraction of flavonoids from green tea, red wine, and urine samples. The nanocomposite is taking advantage of the high surface area of GO and the magnetic phase separation feature of the magnetic sorbent. The nanocomposite is recyclable and was applied to the extraction of flavonoids prior to their determination by HPLC. The effects of amount of surfactant, pH value of the sample solution, extraction time, and desorption condition on the extraction efficiency, and the regeneration conditions were optimized. The limits of detection for luteolin, quercetin and kaempferol range from 0.2 to 0.5 ng mL −1 in urine, from 3.0 to 6.0 ng mL −1 in green tea, and from 1.0 to 2.5 ng mL −1 in red wine. The recoveries are between 82.0 and 101.4 %, with relative standard deviations of <9.3 %.

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

“…Another common synthetic procedure is the solvothermal approach, in which GO is added in a dispersion of a Fe 3+ salt (e.g., ferric chloride hexahydrate) and sodium acetate, under vigorously stirring for 30 min at room temperature [33,40]. The dispersion is transferred in an autoclave and heated under reflux for a specific time span.…”

“…Table 1 summarizes the applications of GO/Fe 3 O 4 for the MSPE of organic compounds from biological, environmental and food samples. Regarding the analysis of biological samples, graphene oxide has been employed for the MSPE of tamsulosin hydrochloride [43], pseudoephedrine [44], psychoactive drugs (including morphine, 6-monoacetylmorphine, amphetamine, methamphetamine, codeine, cocaine, dolantin and benzoylecgonine) [45], methamphetamine [46], flavonoids [33], as well as monohydroxy polycyclic aromatic hydrocarbons [47]. High-performance liquid chromatography (HPLC) with ultraviolet detector (UV), diode array detector (DAD), mass spectrometer (MS), or tandem mass spectrometer (MS/MS) have been employed for the separation and determination of the target analytes.…”

“…Other applications of GO/Fe 3 O 4 for the extraction of organic compounds from food samples include the extraction of patulin from apple juice [56], flavors and fragrances (including ethyl vanillin, trans-cinnamic acid, methyl cinnamate, ethyl cinnamate, and benzyl cinnamate) from orange juice, chocolate and fruit sugar [57], lignans from sesame oil [42], flavonoids from tea, wine and urine samples [33], azo dyes (tartrazine, amaranth, carmine, sunset yellow, allura red) from jellies and candies [40].…”

“…The magnetic GO nanocomposites combine the high adsorption capacity of graphene oxide and the convenience of magnetic separation. Moreover, the hybrid material can be functionalized with different groups to prevent aggregation and extends its application [33,34].Many reviews have been published regarding the applications of graphene and graphene-based sorbents in the field of the sample preparation [35][36][37][38][39]. Herein we aim to discuss the applications of magnetic graphene oxide derived nanomaterials for the extraction and preconcentration of organic compounds from environmental, agricultural, biological and food samples.…”

“…The magnetic GO nanocomposites combine the high adsorption capacity of graphene oxide and the convenience of magnetic separation. Moreover, the hybrid material can be functionalized with different groups to prevent aggregation and extends its application [33,34].…”