Food safety is a prevalent concern around the world. As such, detection, removal, and control of risks and hazardous substances present from harvest to consumption will always be necessary. Metal−organic frameworks (MOFs), a class of functional materials, possess unique physical and chemical properties, demonstrating promise in food safety applications. In this review, the synthesis and porosity of MOFs are first introduced by some representative examples that pertain to the field of food safety. Following that, the application of MOFs and MOF-based materials in food safety monitoring, food processing, covering preservation, sanitation, and packaging is overviewed. Future perspectives, as well as potential opportunities and challenges faced by MOFs in this field will also be discussed. This review aims to promote the development and progress of MOF chemistry and application research in the field of food safety, potentially leading to novel solutions.

A biobased flame retardant toughening agent, phosphaphenanthrene groups-containing triscardanyl phosphate (PTCP), was successfully synthesized via debydrochlorination, epoxidation and ring opening reaction from renewable resource cardanol. The chemical structure of PTCP was confirmed by the proton and phosphorus nuclear magnetic resonance. Epoxy resins (EPs) with different contents of PTCP were prepared through a simple mixing method. Thermogravimetric analysis results indicated that the earlier degradation of PTCP catalyzed the char formation of epoxy resins that was beneficial to protecting underlying polymers from further decomposition. The flame retardant properties were enhanced with the increase of the PTCP content. The EP composite containing 30 wt % PTCP showed a limiting oxygen index of 30.5%. Meanwhile, its peak heat release rate, total heat release and average effective heat of combustion values were decreased by 50%, 27% and 32%, respectively, in comparison to those of neat EP. The enhanced flame retardant behavior was attributed to the improved quality of char residue, which effectively inhibited the flammable volatiles, oxygen and heat transfer between degradation zone and flame zone. The impact strength was increased to 19.14 kJ/m2 for EP/PTCP-30% composite from 14.85 kJ/m2 for neat EP, indicating the toughening effect of PTCP on EP. The findings in this study demonstrated that PTCP could be used as a promising flame retardant toughening agent for epoxy resins to overcome their drawbacks of intrinsic brittle and high flammability.

A novel Pd-catalyzed direct C(sp(3))-H carbonylation of alkylamines for the synthesis of γ-lactams and γ-amino acids has been developed, in which TEMPO was used as the crucial sole oxidant. The synthetic prospect was demonstrated by the concise total synthesis of rac-Pregbalin.

A novel method has been developed to detect two organic arsenic animal feed additives including roxarsone and p-arsanilic acid, as well as other arsenic species such as arsenite, dimethylarsinic acid, monomethylarsonic acid, arsenate, and 4-hydroxyphenylarsonic acid, by using high-performance liquid chromatography coupled to an inductively coupled plasma mass spectrometer (HPLC-ICP-MS). The influence of the type and concentrations of ion-pairing reagents on the separation efficiency of the different arsenic compounds was examined. The effects of the mobile phase pH on the retention of arsenic species on the chromatography column were studied. When a gradient elution procedure was used, the best separation of the seven arsenic species could be achieved in <20 min with a mobile phase consisting of 8% methanol and 92% aqueous tetrabutylammonium hydroxide (4 mM, pH 6.25) followed by 92% trifluoroacetic acid aqueous solution (0.1%, pH 2.0). Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was used as an assistant tool to screen arsenobetain (AsB) in the feed samples by monitoring the reaction at m/z 179-->120. The extractions of arsenic compounds from formula feed samples were studied, and results showed that the extraction with methanol/water (1:1) mixture yielded the most efficient percent compound recovery and the fastest extraction time for all arsenic species. Under optimum conditions, the limits of detection were <1.7 microg of As kg(-1), and the recoveries of all seven arsenic species were >78.5% with the relative standard deviation of <10%. The ion-pair reversed phase HPLC-ICP-MS method was then successfully applied to the speciation of arsenic in feedstuff and formula feed samples.

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A catalyst-free and oxidant-free C-H arylation of xanthenes and thioxanthenes using electrochemistry has been developed, which affords a number of cross-coupling products in moderate to good yields. This method is...

Tris (1,3-dichloro-2-propyl) phosphate (TDCPP) is the most widely used organophosphorus flame retardant, which is now used instead of polybrominated diphenyl ethers (PBDEs). TDCPP has frequently been detected in inorganic environmental matrices, such as soil, water and air as well as biota. In vitro effects of TDCPP on cells had not been previously elucidated. Therefore, in the present study, cytotoxicity, DNA damage, cell cycle distribution, apoptosis caused by TDCPP was studied in RAW264.7 macrophage cells. TDCPP reduced viability of RAW264.7 cells in a concentration-dependent manner and caused damage to DNA that was detected by use of the comet assay and caused up-regulation of the level of γ-H2AX. TDCPP increased the intracellular reactive oxygen species (ROS) level in RAW264.7 cells up to 1.44-fold compared to the control group at 12 hr. Percentages of cells in G1 and G2 phases of the cell cycle were dose-dependently greater in cells exposed to TDCPP. TDCPP significantly down-regulated expression of CDK-4, Cyclin D1, Cyclin B1, CDC-2, which are regulators of G1 and G2 phases of the cell cycle. These results demonstrated that TDCPP is cytotoxic and damages DNA in RAW264.7 cells, which resulted in arrest of the cell cycle at G1 and G2 phases and resulted in apoptosis, suggest the necessity to evaluate the effects of TDCPP on the immune system at the cellular level.

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