A novel nanoassembly was constructed through encapsulating upconversion nanoparticles (UCNPs) into a metal-organic framework structure (ZIF-8), in which doxorubicin (DOX) was absorbed into pores of ZIF-8. The blue emission of UCNPs was quenched by DOX through the fluorescence resonance energy transfer (FRET) strategy. When the nanoprobe was exposed to food samples with different pH values, ZIF-8 collapsed to release DOX molecules, resulting in upconversion recovery. The porous structure of ZIF-8 provides abundant space for DOX absorption, which significantly improves the detection capacities and accuracy. It is shown that the probe has a good linear relationship when pH values vary from 2.5 to 7.4, and can distinguish pH variations as low as 0.5 in real samples. This strategy has been successfully used to determine food spoilage by determination of pH variations.
Keywords: Doxorubicin; Luminescence recovery; Metal–organic framework structure; Nanoprobe; Upconversion nanoparticles; Yellow rice wine.
© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.