College of Food Science and Engineering, Ocean University of China, Qingdao 266003, PR China.
College of Food Science and Engineering, Ocean University of China, Qingdao 266003, PR China; Qingdao Marine Science and Technology Center, Qingdao 266235, PR China.
Food Chem. 2024 Jan 15;431:137131. doi: 10.1016/j.foodchem.2023.137131. Epub 2023 Aug 12.
Hypoxanthine concentration is a potential indicator to evaluate the freshness in the early post-mortem of several aquatic products. Based on MnO in-situ coated upconversion nanoparticles (UCNPs) and xanthine oxidase (XOD), a novel sensor was conducted for the efficient, sensitive determination of hypoxanthine. In this strategy, upconversion fluorescence quenched by MnO would be restored by HO and uric acid (UA), two products from the XOD-catalyzed reactions of hypoxanthine. Through pretreatment with short-time heating and alkylation by N-ethylmaleimide (NEM) to avoid potential interference from reducing substances in the food matrix, this method exhibited satisfactory selectivity. The fluorescence intensity of green emission I was positively proportional to hypoxanthine concentration at a wide range of 0.5-50 mg/L with a detection limit of 0.14 mg/L. Moreover, this convenient method was employed to quantify the hypoxanthine in fish, shrimp, and shellfish samples, showing excellent potential for the application in quality control of aquatic products.
次黄嘌呤浓度是评估几种水产品死后早期新鲜度的潜在指标。基于 MnO 原位包覆上转换纳米粒子（UCNPs）和黄嘌呤氧化酶（XOD），我们构建了一种用于高效、灵敏测定次黄嘌呤的新型传感器。在该策略中，MnO 上转换荧光会被 HO 和尿酸（UA）恢复，HO 和 UA 是次黄嘌呤经 XOD 催化反应生成的两种产物。通过短时间加热预处理和用 N-乙基马来酰亚胺（NEM）进行烷基化处理以避免食品基质中还原物质的潜在干扰，该方法表现出令人满意的选择性。在 0.5-50mg/L 的较宽范围内，绿色发射 I 的荧光强度与次黄嘌呤浓度呈正相关，检测限为 0.14mg/L。此外，该便捷的方法还用于定量测定鱼类、虾类和贝类样品中的次黄嘌呤，显示出在水产品质量控制方面有很好的应用潜力。
