A triple-emission surface molecularly imprinted fluorescence sensor integrated with smartphone for visual detection of curcumin.

Curcumin is extensively existed in plants and is commonly used as food additives. However, excessive intake of curcumin may lead to side effects like nausea and vomiting. Traditional techniques such as high-performance liquid chromatography (HPLC) and liquid chromatography-tandem mass spectrometry (LC-MS) are constrained by cumbersome operations and low efficiency. Herein, a triple-emission surface molecularly imprinted fluorescence sensor (TPP&RhB-SMIPs) was fabricated via precipitation polymerization on halloysite nanotubes (HNTs), using aggregation-induced emission luminogen (AIEgen) TPP-M and allyl rhodamine B as fluorophores. This sensor exhibits distinct fluorescence color transitions (purple-fuchsia-carnation-yellow-chartreuse) with increasing curcumin concentrations, coupled with a linear range of 0.1-4.0 μmol L-1 and a low detection limit of 44 nmol L-1. It demonstrates excellent selectivity and achieves satisfactory recoveries in ginger and beverage samples. A smartphone-integrated portable device was further developed for on-site visual detection of curcumin. This work provides a reliable, rapid, and cost-effective strategy for curcumin analysis, holding great promise for food safety monitoring.