The serious damage of ischemia to brain function has attracted extensive attention. As two of vital signal molecules, development of biosensors for monitoring of hydrogen peroxide (H₂O₂) and pH in vivo is significant to understand the roles of H₂O₂ and pH playing in rat brain followed by ischemia. Herein, a selective and accuracy ratiometric electrochemical biosensor was developed for quantifying H₂O₂ and pH through both current and potential outputs in a rat brain upon ischemia. Catalase (Cat) was first employed as a specific recognition element for both H₂O₂ and pH. Meanwhile, an inner reference molecule, ferrocene (Fc), independent of H₂O₂ and pH, was used as a built‐in correction to improve the accuracy. The reduction peak current of Cat increased with increasing concentration of H₂O₂ from 1.0 to 230 μM. Meanwhile, the peak potential negatively shifted with increasing pH from 5.91 to 7.81, resulting in determination of H₂O₂ and pH. Thus, combined with the remarkable analytical performance of the developed biosensor and the desirable biocompatibility of carbon fibre microelectrode (CFME), a direct and reliable approach was established to monitoring H₂O₂ and pH in the microdialysates collected from rat brain followed by cerebral ischemia.

中文翻译：

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具有双信号输出的电化学生物传感器，用于比例监测大鼠脑微透析液中的H2O2和pH值

缺血对脑功能的严重损害已引起广泛关注。作为两个生命信号的分子，用于监测的过氧化氢（H生物传感器的发展₂ ö ₂）和pH在 体内是显著理解H的角色₂ Ó ₂在大鼠脑中，随后由缺血和pH值播放。在本文中，开发了选择性和精确比例的电化学生物传感器，用于通过缺血时大鼠脑中的电流和电位输出来定量H ₂ O ₂和pH值。过氧化氢酶（Cat）首先被用作H ₂ O ₂的特异性识别元件和pH值。同时，内部参比分子二茂铁（Fc）不受H ₂ O ₂和pH的影响，被用作内置校正来提高准确性。Cat的还原峰值电流随着H ₂ O _2的浓度从1.0增加到230μM而增加。同时，随着pH从5.91增加到7.81，峰电位负移，导致H ₂ O ₂和pH的测定。因此，结合开发的生物传感器的卓越分析性能和所需的碳纤维微电极（CFME）生物相容性，建立了一种直接可靠的方法来监测H ₂ O ₂ 从大鼠大脑收集的微量透析液中的pH和pH，然后进行脑缺血。