In order to protect human health from the threat of excessive acrylamide in heat-processed foods, swift, uncomplicated, highly selective and sensitive online monitoring methods for acrylamide are urgently needed. In this study, a rare earth metal/transition metal-organic frameworks Eu/Zr-MOFs fluorescence sensor with dual-band luminescence was prepared by the solvothermal method for detection of acrylamide in fried potatoes and cookie crumbs. This sensor exhibited two different fluorescence emission peaks at 430 and 615 nm under excitation of 365 nm, and the ratio of fluorescence intensity was linear with the experimental concentration of acrylamide in the range of 1 × 10 −4 to 1 × 10 −3 M. Under the optimal conditions, the proposed fluorescence analysis method showed that the detection limit of acrylamide was as low as 2.4 × 10 −8 M, and the satisfactory recoveries of 94.05–104.04% were obtained for various spiked samples. More importantly, the sensor has ultra-high selectivity for the detection of acrylamide while other small organic molecules hardly interfere with it in the measurement environment. These studies confirmed that the ratiometric fluorescence sensing method was expected to achieve on-line rapid detection of acrylamide in real foods. In addition, the mechanism of Eu/Zr-MOFs sensing of acrylamide was analyzed and discussed in depth, and the analog computation was carried out by Materials Studio software, and the entire sensing system was studied at the micro level in combination with density functional theory.
Tan Long,Xiao Rui,Wu Di,Hu Lianzhe,Zhang Yan,Qi Wenjing
A fast fluorescent dual-emission platform for sensitive detection of sodium dehydroacetate (SDHA) in food is established utilizing bimetallic organic frameworks (Eu@Zr-MOFs). Eu@Zr-MOFs show two fluorescent emissions at 430 nm and 616 nm under single excitation wavelength of 290 nm. Two peaks separated by 180 nm help to eliminate environmental interference and improve the accuracy. In the presence of SDHA, fluorescent intensity at 430 nm and 616 nm shows fluorescent quenching within 1 min. Fluorescent lifetime results show that fluorescent quenching is a static quenching mode. Fluorescent quenching may be ascribed to the diketone structure of SDHA coordinated with Eu 3+ and internal filtering effect. The logarithm of fluorescent intensity (lg I 430 nm * I 616 nm ) has linear relationship with the concentration of SDHA from 0.1 µM to 200 µM with a limit of detection of 31.6 nM. More conveniently, it also achieves visual detection of SDHA through fluorescent color by portable UV lamp and smartphone “color capture” mode. The platform is applied to detect SDHA in fermented and baked food samples. Thus it is an efficient and sensitive fluorescent ratio method for SDHA detection with fast response, high selectivity and accuracy. Graphical
危险品化学品经营许可证（带存储）