食品サンプル中のα-Fe₂O₃@700ナノ粒子修飾スクリーン印刷炭素電極を用いたケルセチンの電気化学的検出の強化

Quercetin (Que), a potent bioactive flavonoid widely found in fruits and vegetables, is renowned for its strong antioxidant, anti-inflammatory, and antiviral properties. Accurate quantification of Que is crucial for evaluating nutritional and therapeutic benefits. In this study, a highly sensitive and selective electrochemical sensor was developed using screen-printed carbon electrodes (SPCEs) modified with calcined hematite nanoparticles (α-Fe₂O₃@700 NPs). The α-Fe₂O₃ NPs, synthesized via a simple co-precipitation method followed by calcination at 700 °C, exhibited a rice grain-like morphology that enhanced electron transport and catalytic activity. The α-Fe₂O₃@700 NPs/SPCE displayed a distinct oxidation peak (Ep) at -0.046 V and a low charge transfer resistance of 573.6 Ω/cm², confirming efficient electron transfer. The sensor achieved a broad linear range (100 nM - 1.5 mM) with a low detection limit of 12.9 nM and excellent reproducibility (RSD = 3.0 %). Recovery studies in real food samples yielded satisfactory results (89.20-104.26 %), and the sensor retained 97.3 % of its initial response after 30 days, indicating high stability. These results demonstrate that α-Fe₂O₃@700 NPs enable a robust and reliable platform for sensitive quercetin detection in complex food matrices.