Dual-emissive bimetallic organic framework hybrids with Eu(III) and Zr(IV) for ratiometric fluorescence sensing of acrylamide in fried and baked foods

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.