@article{Ding2025, 
author = {Haizhen Ding and Shuai Hou and Siqi Zhao and Liping Guo and Ao Sun and Qiuhui Hu and Leiqing Pan and Qiang Liu and Chao Ding},
title = {Fluorescence sensor based on IFE between AEP@UCNPs and oxTMB for the determination of Cd2+ in paddy rice combined with HRP enzyme inhibition mechanism},
year = {2025},
journal = {Food Science and Human Wellness},
volume = {14},
number = {1},
pages = {9250010},
keywords = {Enzyme inhibition, Upconversion nanoparticles (UCNPs), Paddy rice, Cd2+, Inner filter effect (IFE)},
url = {https://www.sciopen.com/article/10.26599/FSHW.2024.9250010},
doi = {10.26599/FSHW.2024.9250010},
abstract = {Cadmium ion (Cd2+) detection technology plays a prominent role in food safety and human health. Herein, we designed and constructed an 2-aminoethyl dihydrogen phosphate (AEP)@upconversion nanoparticles (UCNPs) fluorescence sensor for quantitative detection of Cd2+ in paddy rice based on inner filter effect (IFE) combined with enzyme inhibition mechanism. The AEP modification UCNPs can offer a stable fluorescence donor at 658 nm and be quenched by the oxidized tetramethylbenzidine (oxTMB) catalyzed by horseradish peroxidase (HRP) enzymes. Without addition of Cd2+, the fluorescence of AEP@UCNPs fluorescence sensor was weaken due to the IFE between AEP@UCNPs and oxTMB. With addition of Cd2+, HRP enzyme activity was inhibited by Cd2+, leading to the decreased oxTMB, resulting in the enhance upconversion fluorescence intensity. As a result, the fluorescence intensity signal at 658 nm of the IFE-based AEP@UCNPs fluorescence sensor increased linearly with the increase in Cd2+ in a wide range from 0.5 μmol/L to 6 μmol/L and the limit of detection (LOD) was 24.6 nmol/L. In addition, our proposed IFE-based AEP@UCNPs fluorescence sensor can achieve Cd2+ detection in paddy rice in 30 min.}
}