School of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, China; Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis of Zhejiang Province, Ningbo University, Ningbo 315211, China.
Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2022 Mar 15;269:120734. doi: 10.1016/j.saa.2021.120734. Epub 2021 Dec 11.
Sensitive determination of hypoxanthine (HX), an indicator reflecting the degradation of meat and fish, is significantly important in monitoring food freshness. Herein, we design a novel sensor consisting of orange emissive carbon dots (O-CDs), nitrotetrazolium blue chloride (NTBC), and xanthine oxidase (XOD) for fluorescence turn-off detection of HX. O-CDs, possessing a high fluorescence quantum yield of 37%, are synthesized by hydrothermal treatment of 2,3-diaminopyridine in sulfuric acid. NTBC can react with HX/XOD-generated HO and O to yield a violet-colored formazan, which remarkably quenches the orange fluorescence of O-CDs through inner filter effect. There is a linearity between the quenching efficiency and HX concentration in the range of 2-250 μM, and the limit of detection is 0.61 μM, lower than those of most reported HX sensors. In addition, the proposed method exhibits excellent selectivity, and can be applied to quantify HX in fish samples with satisfactory results.
灵敏测定黄嘌呤（HX），一种反映肉和鱼降解的指标，在监测食品新鲜度方面具有重要意义。在此，我们设计了一种由橙色发射碳点（O-CDs）、硝普化钠蓝氯化物（NTBC）和黄嘌呤氧化酶（XOD）组成的新型传感器，用于荧光关闭检测 HX。O-CDs 通过在硫酸中 2,3-二氨基吡啶的水热处理合成，具有 37%的高荧光量子产率。NTBC 可与 HX/XOD 生成的 HO 和 O 反应，生成紫罗兰色的甲臜，通过内滤效应显着猝灭 O-CDs 的橙色荧光。在 2-250 μM 的范围内，猝灭效率与 HX 浓度之间呈线性关系，检测限为 0.61 μM，低于大多数报道的 HX 传感器。此外，该方法表现出优异的选择性，并可应用于鱼样中 HX 的定量，结果令人满意。
