AbstractThe authors describe an aptamer based method for the determination of the antibiotic sulfadimethoxine (SLF). It is making use of upconversion nanoparticles (UCNPs) that act as an internal fluorophors signals, and of aptamers that can specifically recognize SLF. The UCNPs were deposited on the surface of magnetic nanoparticles (magNPs) functionalized with the aptamer. In the presence of SLF, parts of the UCNPs dissociate from the surface of the magNPs, and this results in decreased fluorescence intensity. The findings were exploited to design a fluorometric assay for SLF that has a 0.11 ng·mL−1 detection limit. The method was successfully applied to the quantification of SLF in spiked samples of perch and catfish. Recoveries range from 80.3% to 92.7%, and RSDs from 2.4% to 3.6%. Graphical AbstractSchematic of an aptamer based method for the determination of the antibiotic sulfadimethoxine (SLF). It is making use of upconversion nanoparticles (UCNPs) that act as an internal fluorophors signals, and of aptamers that can specifically recognize SLF.

中文翻译：

---

基于适体的磺胺二甲氧嘧啶测定，使用磁化上转换纳米粒子

摘要作者描述了一种基于适配体的测定抗生素磺胺二甲氧嘧啶 (SLF) 的方法。它正在利用充当内部荧光团信号的上转换纳米粒子 (UCNP) 和可以特异性识别 SLF 的适体。UCNPs 沉积在用适体功能化的磁性纳米粒子 (magNPs) 的表面。在 SLF 存在下，部分 UCNPs 从 magNPs 表面分离，这导致荧光强度降低。利用这些发现来设计 SLF 的荧光测定法，其检测限为 0.11 ng·mL-1。该方法已成功应用于鲈鱼和鲶鱼加标样品中 SLF 的定量。回收率为 80.3% 至 92.7%，RSD 为 2.4% 至 3.6%。图形摘要基于适配体的测定抗生素磺胺二甲氧嘧啶 (SLF) 方法的示意图。它正在利用充当内部荧光团信号的上转换纳米粒子 (UCNP) 和可以特异性识别 SLF 的适体。