School of Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China.
Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education, Jilin Normal University, Changchun 130103, China.
Molecules. 2024 Jan 31;29(3):661. doi: 10.3390/molecules29030661.
Paper-based test strips with on-site visual detection have become a hot spot in the field of target detection. Yet, low specific surface area and uneven deposition limit the further application of test strips. Herein, a novel "turn-on" ratio of molecularly imprinted membranes (Eu@CDs-MIMs) was successfully prepared based on a Eu complex-doped polyvinylidene fluoride membrane for the selective, rapid and on-site visual detection of norfloxacin (NOR). The formation of surface-imprinted polymer-containing carbon dots (CDs) improves the roughness and hydrophilicity of Eu@CDs-MIMs. Fluorescence lifetimes and UV absorption spectra verified that the fluorescence enhancement of CDs is based on the synergistic effect of charge transfer and hydrogen bonding between CDs and NOR. The fluorescent test strip showed a linear fluorescent response within the concentration range of 5-50 nM with a limit of detection of 1.35 nM and a short response time of 1 min. In comparison with filter paper-based test strips, Eu@CDs-MIMs exhibit a brighter and more uniform fluorescent color change from red to blue that is visible to the naked eye. Additionally, the applied ratio fluorescent test strip was combined with a smartphone to translate RGB values into concentrations for the visual and quantitative detection of NOR and verified the detection results using high-performance liquid chromatography. The portable fluorescent test strip provides a reliable approach for the rapid, visual, and on-site detection of NOR and quinolones.
基于纸的测试条具有现场目视检测功能，已成为目标检测领域的热点。然而，低比表面积和不均匀的沉积限制了测试条的进一步应用。在此，基于掺杂 Eu 配合物的聚偏二氟乙烯膜成功制备了一种新型“开启”比率的分子印迹膜（Eu@CDs-MIMs），用于诺氟沙星（NOR）的选择性、快速和现场目视检测。表面印迹聚合物含碳点（CDs）的形成提高了 Eu@CDs-MIMs 的粗糙度和亲水性。荧光寿命和紫外吸收光谱验证了 CDs 的荧光增强是基于 CDs 和 NOR 之间的电荷转移和氢键协同作用。荧光测试条在 5-50 nM 的浓度范围内表现出线性荧光响应，检测限为 1.35 nM，响应时间短至 1 分钟。与基于滤纸的测试条相比，Eu@CDs-MIMs 表现出更亮、更均匀的荧光颜色变化，从红色变为蓝色，肉眼可见。此外，应用比例荧光测试条与智能手机结合，将 RGB 值转换为浓度，用于 NOR 和喹诺酮类药物的可视化和定量检测，并使用高效液相色谱法验证了检测结果。便携式荧光测试条为快速、可视化和现场检测 NOR 和喹诺酮类药物提供了一种可靠的方法。
