Highly sensitive detection of H₂O₂ and glucose is critical for fundamental research and disease diagnosis. A ratiometric sensor can simultaneously afford two readout signals that provide an internally normalized response to change, thereby reducing false results and improving detection accuracy. A novel ratiometric fluorescent nanosensor for ultrasensitive detection of hydrogen peroxide and glucose was constructed on the basis of the peroxidase-like properties of a hierarchical cobalt/carbon nanotube hybrid nanocomplex (Co-CNT). The as-prepared Co-CNT catalyzes the transformation of the non-fluorescent Amplex Red (AR) into a fluorescent derivative and the transformation of fluorescent scopoletin (SC) into a non-fluorescent derivative in the presence of H₂O₂. The sensing system changes colour from yellow to blue, which can be clearly seen with the naked eye. With the fluorescence ratio of AR to SC as readout, the detection limit of H₂O₂ reaches as low as 100 nM. The developed assay is further utilized for determining H₂O₂-related oxidase reactions with the glucose and glucose oxidase system as model. Glucose can be selectively and sensitively detected as low as 150 nM. Satisfactory recoveries are obtained for glucose detection in serum samples. The developed assay is simple in terms of preparation and operation and provides a straightforward method for cost-effective and reliable detection of H₂O₂ and H₂O₂-related reactions in clinical diagnosis and biomedical applications.

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H ₂ O ₂和葡萄糖的高灵敏度检测对于基础研究和疾病诊断至关重要。比例传感器可以同时提供两个读出信号，以提供内部标准化的变化响应，从而减少错误结果并提高检测精度。基于分级钴/碳纳米管杂化纳米复合物（Co-CNT）的过氧化物酶样性质，构建了一种用于过氧化氢和葡萄糖超灵敏检测的新型比例荧光纳米传感器。所制备的Co-CNT在H ₂ O存在下催化非荧光双链红（AR）向荧光衍生物的转化以及荧光大戟素（SC）向非荧光衍生物的转化。₂。传感系统的颜色从黄色变为蓝色，可以用肉眼清楚地看到。以AR与SC的荧光比作为读数，H ₂ O ₂的检出限低至100 nM。以葡萄糖和葡萄糖氧化酶系统为模型，将开发的测定法进一步用于确定H ₂ O ₂相关的氧化酶反应。可以选择性和灵敏地检测到低至150 nM的葡萄糖。对于血清样品中的葡萄糖检测，回收率令人满意。所开发的测定法在制备和操作方面都很简单，并提供了一种简单有效的方法来经济有效地检测H ₂ O ₂和H ₂O ₂相关反应在临床诊断和生物医学应用中。

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