An enzyme-based amperometric biosensor was fabricated for detecting hydrogen peroxide (H₂O₂). Horseradish peroxidase (HRP) was modified using functionalized fluorescent gold nanoclusters (AuNCs) via biomineralization. HRP-AuNCs were successfully immobilized on multiwalled carbon nanotube- (MWCNT-) coated carbon fiber ultramicroelectrodes (CFUMEs). The AuNCs, which act as molecular electric wires, effectively promote the electron transfer between the enzyme active center and the electrode. Additionally, the HRP conjugated with the AuNCs retains its biological activity, which enables the catalytic reaction of H₂O₂. The HRP-AuNCs/MWCNTs/CFUMEs have been proven as excellent amperometric sensors for H₂O₂. The sensitivity of the H₂O₂ biosensor is , and the detection limit is estimated to be 443 nM. Furthermore, the biosensor exhibited long-term stability and good reproducibility. Moreover, the biosensor has been tested by determining the H₂O₂ concentration in calf serum samples.

中文翻译：

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基于多壁碳纳米管和辣根过氧化物酶-金纳米簇生物共轭物固定化的安培生物传感器检测H2O2

制作了一种基于酶的安培生物传感器，用于检测过氧化氢（H ₂ O ₂）。辣根过氧化物酶（HRP）使用功能化的荧光金纳米簇（AuNCs）进行了生物矿化处理。HRP-AuNCs已成功固定在多壁碳纳米管-（MWCNT-）涂层的碳纤维超微电极（CFUMEs）上。作为分子电线的AuNCs有效地促进了酶活性中心和电极之间的电子转移。另外，与AuNC结合的HRP保留了其生物学活性，这使得H ₂ O ₂能够进行催化反应。HRP-AuNC / MWCNT / CFUME已被证明是用于H ₂ O的出色的安培传感器₂。H ₂ O ₂生物传感器的灵敏度为，并且检测极限估计为443 nM。此外，该生物传感器表现出长期稳定性和良好的再现性。此外，已经通过确定小牛血清样品中的H ₂ O ₂浓度对生物传感器进行了测试。