Abstract：
The 5-nitroimidazole (5-NI) class of antibiotics, such as metronidazole, ornidazole, secnidazole, and tinidazole, are widely used to prevent bacterial infection in humans and livestock industries. However, their overuse contaminates the farmed animal products and water bodies. Hence, a selective, sensitive, and cost-effective method to detect 5-NI antibiotics is the need of the hour. Herein, we report a rapid, inexpensive, and efficient sensing system to detect 5-NI drugs using an as-prepared solution of ε-poly-l-lysine (ε-PL), a naturally occurring and biodegradable homopolypeptide that has an intrinsic fluorescence via clustering-triggered emission. The low nanomolar detection limit (3.25-3.97 nM) for the aforementioned representative 5-NI drugs highlights the sensitivity of the system, outperforming most of the reported sensors alike. The resulting fluorescence quenching was found to be static in nature. Importantly, excellent recovery (100.26-104.41%) was obtained for all real samples and animal products tested. Visual detection was demonstrated by using paper strips and silica gel for practical applications. Furthermore, ε-PL could detect 5-NI antibiotics in living 3T3-L1 mouse fibroblast cells via cellular imaging. Taken together, the present work demonstrates the detection of 5-NI antibiotics using a biocompatible natural polypeptide, ε-PL, and represents a simple and inexpensive analytical tool for practical application.
摘要：
5-硝基咪唑（5-NI）类抗生素，如甲硝唑，奥硝唑,塞克硝唑,还有替硝唑,广泛用于预防人类和畜牧业的细菌感染。然而,它们的过度使用污染了养殖动物产品和水体。因此，一个选择性的，敏感,和经济有效的方法来检测5-NI抗生素是小时的需要。在这里，我们报告了一个快速的，便宜,和使用制备的ε-聚-1-赖氨酸（ε-PL）溶液检测5-NI药物的有效传感系统，一种天然存在的和可生物降解的同源多肽，通过聚类触发的发射具有内在荧光。上述代表性5-NI药物的低纳摩尔检测限（3.25-3.97nM）突出了系统的灵敏度，优于大多数报告的传感器。发现所得的荧光猝灭本质上是静态的。重要的是,所有实际样品和动物产品均获得了优异的回收率(100.26-104.41%)。通过使用纸条和硅胶进行实际应用，证明了视觉检测。此外，ε-PL可以通过细胞成像检测活3T3-L1小鼠成纤维细胞中的5-NI抗生素。一起来看,目前的工作证明了使用生物相容性天然多肽检测5-NI抗生素，ε-PL,并代表了一种简单而廉价的实际应用分析工具。
