One‐step deep eutectic solvent strategy for efficient analysis of aflatoxins in edible oils

Abstract

BACKGROUND Aflatoxins, a kind of carcinogen, have attracted increasing attention due to their toxicity and harmfulness to human health. Traditional methods for aflatoxins analysis usually involve tedious extraction steps with a subsequent derivatization process. Herein, a simple and efficient liquid‐phase microextraction method based on deep eutectic solvents (DESs) for direct analysis of aflatoxins was developed. RESULTS Adopting DESs as the extractant, we surprisingly found out that DESs could either achieve good extraction performance or play a similar role to the derivatization agent, achieving an enhancement of fluorescence intensity for direct analysis of aflatoxins by high‐performance liquid chromatography combined with fluorescent detection. Under optimal conditions obtained by response surface methodology, the method provided satisfactory linear ranges (0.01–0.75 μg kg−1 for AFB1 and AFG1, 0.003–0.25 μg kg−1 for AFB2 and AFG2) with good determination coefficients (R2 > 0.9988), a low detection limit (0.0005–0.003 μg kg−1), and good recovery rates (72.05–113.54%). CONCLUSION These results highlighted superiorities of the one‐step DES strategy for analysis of aflatoxins in edible oils, providing insights for future development of efficient methods in food analysis. © 2020 Society of Chemical Industry

Deep Eutectic Solvents Application in Food Analysis

“…[60] As can be seen in the table, hydrophilic DESs have been used with very good performances for the preconcentration and extraction of an extensive diversity of analytes, including both organic compounds (i.e., antioxidants [25], polycyclic aromatic hydrocarbons (PAHs) [65], pesticides [53][54][55][56], amino acids [24], phenolic compounds and caffeine [10,35,38,52,60], flavonoids [29,32], anthocyanins [31,34,58], mycotoxins [33,37], aflatoxins [39], sex hormones [36], antibiotics [41], preservatives [67], organophosphorus pesticides (OPPs) [44,57], curcumin [22,25,40,45], polybrominated diphenyl ethers (PBDEs) [43], and organochlorine pesticides (OCPs) [43,72]) and metals (Cd, Zn, As, Sb, Fe, Cu, Se, Mn, Pb, Cr, Co, Hg and Al [11][12][13][14][15]23,[26][27][28]42,[46][47]…”

“…Among them, the speed, simplicity and low-cost of DLLME has made it the most widely used, allowing the preconcentration of different analytes in a wide variety of food matrices. It is important to highlight that in most cases, the hydrophilic DESs have been dispersed through various physical processes (manual agitation [53], ultrasound [14,30,38,39,44,46,47,50,51,[61][62][63]70,73] or vortex stirring [12,13,22,33,40,43,45,48,49,52,59,63,69], temperature change [57], or air bubbled when pulling-pushing a syringe [42,55,64,71]), using few microliters of the extraction solvent and without the need for organic solvents. Additionally, some applications in which the drop obtained after the extraction stage has been solidified can be found [48,68], which allows the recovery of the complete drop and makes the procedure simpler, safer and faster [73].…”

“…After the application of the DESs as extraction solvents in the above-mentioned procedures, analytes have generally been determined by HPLC or ultra-high-performance liquid chromatography (UHPLC) using different detection systems, such as UV [21,[29][30][31][32]44,52,57,70,73], diode array detector (DAD) [10,25,35,36,59,67], FD [37,39,60,65], tandem mass spectrometry (MS/MS) [33], as a result of their appropriate solubility in the mobile phase, or ICP-MS, this last for free seleno-amino acids determination [24]. However, they have also been separated and detected by UV-Vis spectrophotometry [14,22,38,40,45], atomic absorption spectroscopy (AAS) [11,23,47,68], slotted quartz tube-flame AAS [48,49], hydride generation AAS [12], graphite furnace AAS [15,26,42], ETAAS [13,27,46,50,51,71] and ICP-optical emission spectroscopy (OES) [28].…”

“…The great extraction capacity shown by the hydrophilic DESs together with the sophisticated detection techniques used, have allowed to obtain low LODs, in the order of µg/L or µg/kg in most cases as can be seen in Table 1, or even ng/L or ng/kg [12,13,39,42,46,65,71].…”