A novel fluorescence immunoassay based on AgNCs and ALP for ultrasensitive detection of sulfamethazine (SMZ) in environmental and biological samples
A novel fluorescence immunoassay based on AgNCs and ALP for ultrasensitive detection of sulfamethazine (SMZ) in environmental and biological samples
复制标题
一种基于 AgNC 和 ALP 的新型荧光免疫分析方法，用于超灵敏检测环境和生物样品中的磺胺二甲嘧啶 (SMZ)
DOI：
10.1016/j.talanta.2019.01.103
复制
发表时间：
2019
期刊：
影响因子：
6.1
通讯作者：
Zhang Zhen
中科院分区：
文献类型：
--
作者：
Zhu Nuanfei;Zhu Yuqi;Wang Jin;Gyimah Eric;Hu Xialin;Zhang Zhen
建立了一种基于I-to银簇（agnc）猝灭的间接竞争荧光免疫分析法，用于磺胺乙嗪（SMZ）的高选择性和超灵敏检测。在该系统中，碱性磷酸酶（ALP）被标记在二抗（Ab2）上。磷酸抗坏血酸镁在ALP的催化作用下，经过一个竞争步骤可催化生成抗坏血酸。随后，引入i2，并在抗坏血酸存在下进一步还原为i，触发分散在异丙醇（IPA）缓冲液中的agnc的荧光猝灭。更重要的是，痕量i会导致荧光信号明显减弱，表明该方法的灵敏度将大大提高。在最佳条件下，改进的SMZ检测方法检出限较低（LOD为0.05000 μg/L），检出范围较宽（0.1400 ~ 71.71 μg/L）。经评价，所建立的荧光酶联免疫吸附测定法具有良好的准确度和可靠性（回收率为84.18 ~ 118.6%；CV为2.03 ~ 7.64%），在环境和生物样品中痕量SMZ的检测中具有良好的性能和潜力。
A novel indirect competitive fluorescence immunoassay based on the quenching of I-to silver clusters (AgNCs) was developed for the highly selective and ultrasensitive detection of sulfamethazine (SMZ). In this system, alkaline phosphatase (ALP) was labeled on the secondary antibody (Ab2). And after a competition step, magnesium ascorbyl phosphate could be catalyzed to produce ascorbic acid under the catalysis of ALP. Subsequently, I2was introduced and further reduced to I-in the presence of ascorbic acid, triggering the fluorescence quenching of AgNCs dispersed in isopropanol (IPA) buffer. More importantly, trace I-could lead to an obvious reduction in fluorescence signal, indicating the sensitivity of this method would be greatly improved. Under the optimal condition, this improved method for the SMZ detection has a lower detection of limit (LOD, 0.05000 μg/L) with a wider range (0.1400–71.71 μg/L). After an evaluation, the fluorescence ELISA proposed in this work has satisfactory accuracy and reliability (recoveries, 84.18–118.6%; CV, 2.03–7.64%), illustrating good performance and great potential for the detection of trace SMZ in environmental and biological samples.