Abstract：
In this work, we present a novel colorimetric sensing platform for the sensitive detection of ethamsylate (ETM) usingultrathin MnO2 nanosheets with enhancedoxidase-mimicking activity. A facile template-free hydrothermal process was applied to synthesize the MnO2 nanosheets under mild conditions. The nanosheets exhibited oxidase-mimicking activity, facilitating the conversion of TMB into the blue-colored oxTMB in the absence of H2O2. However, the presence of ETM inhibited this activity, resulting in the conversion of oxTMB back to colorless TMB and a substantial decrease in the blue color intensity. The colorimetric response exhibited a linear relationship with ETM concentration over the range of 0.5 to 10.0 µg/mL and a detection limit of 0.156 µg/mL. To further elucidate the underlying mechanism, we performed extensive characterization and kinetic experiments. The findings demonstrated that this unique property is attributed to the remarkable capacity of the MnO2 nanosheets to absorb oxygen, producing superoxide radicals (O2-). The oxidase-mimicking activity of the nanosheets was further confirmed by the reaction kinetics, following Michaelis-Menten\'s behavior. Moreover, the applicability of the sensing platform was assessed by determining ETM concentrations in various real samples (different pharmaceuticals, human plasma, and environmental water). The well-established platform demonstrates the prospective role that nanomaterials-based sensing platforms may play in clinical diagnostics, pharmaceutical analysis, and other relevant fields.
摘要：
在这项工作中,我们提出了一种新颖的比色传感平台，用于使用超薄的MnO2纳米片对乙胺磺酸盐（ETM）进行灵敏检测。在温和条件下，采用了一种简便的无模板水热法来合成MnO2纳米片。纳米片表现出氧化酶模拟活性，在不存在H2O2的情况下促进TMB向蓝色oxTMB的转化。然而,ETM的存在抑制了这种活动，导致oxTMB转化回无色TMB和蓝色强度的显著降低。在0.5至10.0µg/mL的范围内，比色响应与ETM浓度呈线性关系，检出限为0.156µg/mL。为了进一步阐明潜在的机制，我们进行了广泛的表征和动力学实验。研究结果表明，这种独特的特性归因于MnO2纳米片吸收氧气的显着能力，产生超氧自由基（O2-）。通过反应动力学进一步证实了纳米片的氧化酶模拟活性，跟随米迦勒-门顿的行为。此外，通过确定各种实际样品中的ETM浓度（不同的药物，人血浆,和环境水)。完善的平台展示了基于纳米材料的传感平台在临床诊断中可能发挥的前瞻性作用。药物分析,和其他相关领域。
