Fe3O4/hydroxyapatite/graphene quantum dots as a novel nano-sorbent for preconcentration of copper residue in Thai food ingredients: Optimization of ultrasound-assisted magnetic solid phase extraction

Abstract

FeO/hydroxyapatite/graphene quantum dots (FeO/HAP/GQDs) nanocomposite was synthesized and used as a novel magnetic adsorbent. This nanocomposite was characterized using scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, and magnetization property. The FeO/HAP/GQDs was applied to pre-concentrate copper residues in Thai food ingredients (so-called "Tom Yum Kung") prior to determination by inductively coupled plasma-atomic emission spectrometry. Based on ultrasound-assisted extraction optimization, various parameters affecting the magnetic solid-phase extraction, such as solution pH, amount of magnetic nanoparticles, adsorption and desorption time, and type of elution solvent and its concentration were evaluated. Under optimal conditions, the linear range was 0.05-1500ngmL (R>0.999), limit of detection was 0.58ngmL, and limit of quantification was 1.94ngmL. The precision, expressed as the relative standard deviation of the calibration curve slope (n=5), for intra-day and inter-day analyses was 0.87% and 4.47%, respectively. The recovery study of Cu for real samples was ranged between 83.5% and 104.8%. This approach gave the enrichment factor of 39.2, which guarantees trace analysis of Cu residues. Therefore, FeO/HAP/GQDs can be a potential and suitable candidate for the pre-concentration and separation of Cu from food samples. It can easily be reused after treatment with deionized water.

Graphene Quantum Dots and Enzyme-Coupled Biosensor for Highly Sensitive Determination of Hydrogen Peroxide and Glucose

“…In recent years, various kinds of methods have been applied in glucose quantitative analysis in different samples, including electrometric [ 5 ], voltammetric [ 6 ], colorimetric [ 7 ] and fluorimetric detection [ 8 , 9 ]. Fluorescence detection is a current research interest in analyzing food [ 10 ], diagnosing of diabetes [ 11 , 12 ], etc. Because of the convenient implementation and high sensitivity, several types of bio-probes have been made using enzymes and some fluorescent material for fast and deep sensing detection [ 13 , 14 ].…”

Activated carbon/diatomite‐based magnetic nanocomposites for magnetic solid‐phase extraction of S‐phenylmercapturic acid from human urine

“…The morphological structures of bare Fe 3 O 4 nanoparticles (NPs) and AC/DBMNs were characterized by SEM and TEM. Figure 2(a and b) clearly shows that the synthesized bare Fe 3 O 4 NPs consist of large quantities of sphere‐shaped particles and form agglomerates with asymmetric distributions, which is inherent to the iron oxide magnetic nanoparticles (Musa, Wan Ibrahim, Mohd Marsin, Abdul Keyon, & Rashidi Nodeh, 2018; Sricharoen et al, 2017). Figure 2(c and d) reveals that most of the prepared AC/DBMNs are approximately spherical and uniform particles, which is similar to the previous report (Akbari‐Jonoush et al, 2016).…”

New approach applying a pet fish air pump in liquid‐phase microextraction for the determination of Sudan dyes in food samples by HPLC

“…The result of sample preparation is discussed and shown in Supporting Information, Fig. S3, S4, and Table S1 .…”