A high sensitive and selective hydrogen peroxide (H₂O₂) biosensor was fabricated on the basis of reduced hemoglobin (Hb) and single-walled carbon nanotubes (SWCNTs) for detecting the release of H₂O₂ from living HepG2 cancer cells in the process of the in situ biosynthesis of ZnO quantum. The modification of carbon fiber microelectrode (CFME) was carried out by physical adsorption. By the scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), the dense cover of surface and successful immobilization were characterized. Electrochemical investigation demonstrates that the as-prepared modified microelectrode showed a quasi-reversible process toward the reduction of H₂O₂, which exhibited a linear range from 0.51 to 10.6 μM, with a limit of detection of 0.23 μM. This microelectrode biosensor was applied for the quantification of the change of H₂O₂ concentration released from HepG2 cells through the in situ biosynthesis of ZnO quantum dots, which was further confirmed by the fluorescence staining.

中文翻译：

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通过基于微电极的酶生物传感器监测细胞内过氧化氢的动态释放

在还原的血红蛋白（Hb）和单壁碳纳米管（SWCNT）的基础上，制造了一种高灵敏度和选择性的过氧化氢（H ₂ O ₂）生物传感器，用于检测HpG2活细胞中H ₂ O ₂的释放。ZnO量子原位生物合成的过程 碳纤维微电极（CFME）的改性是通过物理吸附进行的。通过扫描电子显微镜（SEM）和能量色散X射线光谱（EDS），表征了致密的表面覆盖和成功的固定化。电化学研究表明，所制备的修饰微电极对还原H ₂ O ₂具有准可逆的过程。的线性范围为0.51至10.6μM，检出限为0.23μM。该微电极生物传感器用于通过原位生物合成ZnO量子点从HepG2细胞释放的H ₂ O ₂浓度的定量，这通过荧光染色进一步证实。