g-C3N4/Fe3O4 Nanocomposites as Adsorbents Analyzed by UPLC-MS/MS for Highly Sensitive Simultaneous Determination of 27 Mycotoxins in Maize: Aiming at Increasing Purification Efficiency and Reducing Time

Fluorine-Functionalized Triazine-Based Porous Organic Polymers for the Efficient Adsorption of Aflatoxins

Food safety issue caused by aflatoxins has aroused widespread concern in society. Herein, a novel fluorine-functionalized triazine-based porous organic polymer (F-POP) was developed for the first time by the simple condensation polymerization of 2,2'-bis(trifluoromethyl)benzidine and cyanuric chloride. With in-built fluorine functional group (F) and imine group (-NH-), F-POP displayed significantly superior adsorption ability for aflatoxins, outperforming fluorine-free POP due to the multiple interaction mechanisms of hydrogen bond, F-O interaction, π-π interaction, F-π interaction, and hydrophobic interaction. Thus, magnetic F-POP was prepared by introducing Fe₃O₄ into F-POP and then utilized as a magnetic sorbent for the extraction of trace aflatoxins in peanut and rice samples prior to high-performance liquid chromatography-fluorescence detection. Under the optimal conditions, the proposed method presented high sensitivity with the limit of detections at 0.005-0.15 ng g^-1. F-POP also exhibited outstanding adsorption capability for many other organic pollutants, revealing its great potential for analysis or adsorption applications.

Recent advances in simultaneous detection strategies for multi-mycotoxins in foods

Mycotoxin contamination has become a challenge in the field of food safety testing, given the increasing emphasis on food safety in recent years. Mycotoxins are widely distributed, in heavily polluted areas. Food contamination with these toxins is difficult to prevent and control. Mycotoxins, as are small-molecule toxic metabolites produced by several species belonging to the genera Aspergillus, Fusarium, and Penicillium growing in food. They are considered teratogenic, carcinogenic, and mutagenic to humans and animals. Food systems are often simultaneously contaminated with multiple mycotoxins. Due to the additive or synergistic toxicological effects caused by the co-existence of multiple mycotoxins, their individual detection requires reliable, accurate, and high-throughput techniques. Currently available, methods for the detection of multiple mycotoxins are mainly based on chromatography, spectroscopy (colorimetry, fluorescence, and surface-enhanced Raman scattering), and electrochemistry. This review provides a comprehensive overview of advances in the multiple detection methods of mycotoxins during the recent 5 years. The principles and features of these techniques are described. The practical applications and challenges associated with assays for multiple detection methods of mycotoxins are summarized. The potential for future development and application is discussed in an effort, to provide standards of references for further research.

A novel magnetic metal-organic framework absorbent for rapid detection of aflatoxins B1B2G1G2 in rice by HPLC-MS/MS

In this study, a core-shell-structured magnetic metal-organic framework (MMOF) composite material (Fe₃O₄@UiO-66-NH₂) was synthesized by the solvothermal method. It was employed as a new absorbent in combination with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for the simultaneous detection of four aflatoxins (AFs) in rice. This method could shorten the pre-processing time by exploiting the advantageous characteristics of magnetic cores. The impurity was removed quickly. The effects of extraction solution, extraction time, adsorbent types, and amount of adsorbent on the extraction rate of target compounds were optimized. Under optimized conditions, AFs were validated and showed a good linear relationship within the 0.375-20 μg kg^-1 concentration range (r² > 0.9992). The limit of detection (LOD) was 0.0188-0.1250 μg kg^-1 and the limit of quantification (LOQ) was 0.0375-0.3750 μg kg^-1. At three spiking levels (0.375, 2, and 10 μg kg^-1), the average recovery values for the four AFs ranged from 85.1% to 111.0%. The relative standard deviation ranged from 3.4% to 7.7%. The new method proved to be simple, fast, efficient, and suitable for the determination of AFs in rice samples.

Application of Nanomaterials for Coping with Mycotoxin Contamination in Food Safety: From Detection to Control

Mycotoxins, which are toxic secondary metabolites produced by fungi, are harmful to humans. Mycotoxin-induced contamination has drawn attention worldwide. Consequently, the development of reliable and sensitive detection methods and high-efficiency control strategies for mycotoxins is important to safeguard food industry safety and public health. With the rapid development of nanotechnology, many novel nanomaterials that provide tremendous opportunities for greatly improving the detection and control performance of mycotoxins because of their unique properties have emerged. This review comprehensively summarizes recent trends in the application of nanomaterials for detecting mycotoxins (fluorescence, colorimetric, surface-enhanced Raman scattering, electrochemical, and point-of-care testing) and controlling mycotoxins (inhibition of fungal growth, mycotoxin absorption, and degradation). These detection methods possess the advantages of high sensitivity and selectivity, operational simplicity, and rapidity. With research attention on the control of mycotoxins and the gradual excavation of the properties of nanomaterials, nanomaterials are also employed for the inhibition of fungal growth, mycotoxin absorption, and mycotoxin degradation, and impressive controlling effects are obtained. This review is expected to provide the readers insight into this state-of-the-art area and a reference to design nanomaterials-based schemes for the detection and control of mycotoxins.

Rapid determination of 2,4-diaminopyrimidine residues through sample pretreatment using immunomagnetic bead purification along with HPLC-UV

To reduce matrix interference and realize simultaneous detection of multiple homologous compounds (trimethoprim (TMP), diaveridine (DVD), ormetoprim (OMP), baquiloprim (BQP), and aditoprim (ADP) in pig, cattle, chicken, and fish muscles), an immunomagnetic bead (IMB)-based sample purification pretreatment with HPLC-UV was developed. A broad-spectrum monoclonal antibody (mAb, named 14C6) was prepared and conjugated with carboxylic-acid-functionalized magnetic nanoparticles using the active ester method to obtain IMBs for sample purification. The extraction solvent was optimized based on the extraction efficiency. Good linearity was observed for all the five analytes (10-200 μg/kg) with the LOD and LOQ of 5 and 10 μg/kg, respectively. The mean recoveries ranged from 62.5% to 76.9%, while the coefficient of variation was <12.2%. The IMB method afforded greater sample purification and enrichment than those achieved with the SPE column-based conventional method. Hence, the IMB-based sample purification is a useful tool to determine 2,4-diaminopyrimidine residues in edible animal tissues.

Current Applications of Magnetic Nanomaterials for Extraction of Mycotoxins, Pesticides, and Pharmaceuticals in Food Commodities

Environmental pollutants, such as mycotoxins, pesticides, and pharmaceuticals, are a group of contaminates that occur naturally, while others are produced from anthropogenic sources. With increased research on the adverse ecological and human health effects of these pollutants, there is an increasing need to regularly monitor their levels in food and the environment in order to ensure food safety and public health. The application of magnetic nanomaterials in the analyses of these pollutants could be promising and offers numerous advantages relative to conventional techniques. Due to their ability for the selective adsorption, and ease of separation as a result of magnetic susceptibility, surface modification, stability, cost-effectiveness, availability, and biodegradability, these unique magnetic nanomaterials exhibit great achievement in the improvement of the extraction of different analytes in food. On the other hand, conventional methods involve longer extraction procedures and utilize large quantities of environmentally unfriendly organic solvents. This review centers its attention on current applications of magnetic nanomaterials and their modifications in the extraction of pollutants in food commodities.