The abuse of ciprofloxacin (CIP) in stock industries causes the residue in food stuffs and the leakage in the environment, impairing human health and ecological balance. Based on the competitive coordination of CIP with Al³⁺ and the inherent fluorescence of CIP, Al-based metal-organic framework NH₂-MIL-53 was herein prepared as the ratiometric probe for CIP residue by integrating fluorescence with scattering signals. Considering the overlapped emission of NH₂-MIL-53 with CIP, 8-hydroxy-2-quinolinecarboxaldehyde (HQCA) was further modified on NH₂-MIL-53 via Schiff base reaction to produce non-fluorescent HQCA-MIL-53, for reducing the background signal and improving the detection sensitivity. After adding CIP to HQCA-MIL-53, the competitive coordination of CIP with Al³⁺ made HQCA-MIL-53 decomposed, reducing the second-order scattering signal at 660 nm, while the inherent emission of CIP made the fluorescence signal at 425 nm observed. And expectably, HQCA-MIL-53 displayed high sensitivity toward CIP and the limit of detection was determined as low as 52 nM ascribed to HQCA-reduced background signal. HQCA-MIL-53 was finally applied to analyzing the CIP residue in basa fish, tap water and human urine. Overall, this work develops a ratiometric probe for the sensitive detection of CIP residue, also paves the way to construct ratiometric CIP probes with the fluorescence-scattering strategy.

畜牧业滥用环丙沙星（CIP）导致食品残留和环境泄漏，损害人体健康和生态平衡。基于CIP与Al ³⁺的竞争性配位以及CIP固有的荧光性，本文通过整合荧光与散射信号制备了Al基金属有机骨架NH ₂ -MIL-53作为CIP残基的比率探针。_{考虑到 NH 2} -MIL-53 与 CIP的重叠发射，8-羟基-2-喹啉甲醛 (HQCA) 在 NH _{2上进一步改性}-MIL-53 通过席夫碱反应产生非荧光HQCA-MIL-53，用于降低背景信号并提高检测灵敏度。在 HQCA-MIL-53 中加入 CIP 后，CIP 与 Al ^{3+的竞争配合}使 HQCA-MIL-53 分解，降低了 660 nm 处的二阶散射信号，而 CIP 的固有发射使得观察到了 425 nm 处的荧光信号。并且可以预期，HQCA-MIL-53 对 CIP 显示出高灵敏度，并且由于 HQCA 降低的背景信号，检测限被确定为低至 52 nM。HQCA-MIL-53 最终应用于分析巴沙鱼、自来水和人尿中的 CIP 残留。总体而言，这项工作开发了一种用于灵敏检测 CIP 残留的比率探针，也为构建具有荧光散射策略的比率 CIP 探针铺平了道路。