Ofloxacin (OFL) is often abused in medicine and animal husbandry, which poses a great threat to human health and ecological environment. Therefore, it is necessary to establish efficient method to detect OFL. Electrochemical sensor has attracted widespread attention due to the advantages of low cost and fast response. However, most electrochemical sensors usually use one response signal to detect the target, which makes it sensitive to the variable background noise in the complex environment, resulting in low robustness and selectivity. The ratio detection mode and employing molecularly imprinted polymer (MIP) are two strategies to solve these problems. A novel molecular imprinting polymer-ratiometric electrochemical sensor (MIP-RECS) based on Fe-MOF-NH/CNTs-NH/MXene composite was prepared for the rapid and sensitive detection of OFL. The positively charged Fe-MOF-NH and CNTs-NH as interlayer spacers were introduced into the negatively charged MXene through a simple electrostatic self-assembly technique, which effectively prevented the agglomeration of MXene and increased the electrocatalytic activity. A glass carbon electrode was modified by the composite and a MIP film was electropolymerized on it using -phenylenediamine and β-cyclodextrin as bifunctional monomers and OFL as template. Then a MIP-RECS was designed by adding dopamine (DA) into the electrolyte solution as internal reference, and OFL was quantified by the response current ratio of OFL to DA. The current ratio and the concentration of OFL displayed a satisfying linear relationship in the range of 0.1 μM–100 μM, with a limit of detection (LOD) of 13.2 nM. Combining molecular imprinting strategy and ratio strategy, the MIP-RECS has impressive selectivity compared with the non-imprinted polymer-RECS, and has better repeatability and reproducibility than non-ratiometric sensor. The MIP-RECS has high sensitivity and accuracy, which was applied for the detection of OFL in four different brands of milk and was verified by HPLC method with satisfactory results.

中文翻译：

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结合分子印迹聚合物和 Fe-MOF-NH2/CNTs-NH2/MXene 复合材料的新型比率电化学传感平台，可有效检测氧氟沙星


氧氟沙星（OFL）在医药和畜牧业中经常被滥用，对人类健康和生态环境造成极大威胁。因此，有必要建立有效的OFL检测方法。电化学传感器由于成本低廉、响应速度快等优点而受到广泛关注。然而，大多数电化学传感器通常使用单一响应信号来检测目标，这使得其对复杂环境中变化的背景噪声敏感，导致鲁棒性和选择性较低。比率检测模式和采用分子印迹聚合物（MIP）是解决这些问题的两种策略。制备了一种基于 Fe-MOF-NH/CNTs-NH/MXene 复合材料的新型分子印迹聚合物比率电化学传感器 (MIP-RECS)，用于快速、灵敏地检测 OFL。通过简单的静电自组装技术将带正电的Fe-MOF-NH和CNTs-NH作为层间间隔物引入带负电的MXene中，有效防止了MXene的团聚并提高了电催化活性。将该复合材料修饰玻碳电极，以β-苯二胺和β-环糊精为双功能单体，OFL为模板，在其上电聚合MIP薄膜。然后通过在电解质溶液中添加多巴胺(DA)作为内参设计MIP-RECS，并通过OFL与DA的响应电流比来量化OFL。电流比和 OFL 浓度在 0.1 μM–100 μM 范围内呈现令人满意的线性关系，检测限 (LOD) 为 13.2 nM。 结合分子印迹策略和比率策略，MIP-RECS与非印迹聚合物-RECS相比具有令人印象深刻的选择性，并且比非比率传感器具有更好的重复性和再现性。 MIP-RECS具有较高的灵敏度和准确度，用于四种不同品牌牛奶中OFL的检测，并经HPLC方法验证，结果满意。