The reactivity of platinized ultramicroelectrodes (Pt‐black UMEs) towards superoxide anion O₂^.−, an unstable Reactive Oxygen Species (ROS), and its relatives, H₂O₂ and O₂, was studied. Voltammetric studies in PBS demonstrate that Pt‐black UMEs provide: i) a well‐resolved reversible redox signature for O₂^.− detected in both alkaline and physiological buffers (pH 12 and 7.4); ii) irreversible oxidation and reduction waves for H₂O₂ at pH 7.4. The oxygen reduction reaction (ORR) at Pt‐black surfaces solely yields H₂O₂ (2 electrons/2 H⁺) at physiological pH. Consequently, Pt‐black UMEs allow to sense different ROS including superoxide anion for future biomedical or physico‐chemical investigations.

中文翻译：

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镀铂微电极分析磷酸盐缓冲液中超氧阴离子的电活性

研究了铂超微电极（Pt-black UME）对超氧阴离子O ₂ ^.-（一种不稳定的活性氧（ROS））及其亲戚H ₂ O ₂和O _2的反应性。PBS中的伏安研究表明，Pt黑UME提供：i）在碱性和生理缓冲液（pH 12和7.4）中检测到的O ₂ ^.-的可分辨的可逆氧化还原特征。ii）pH 7.4下H ₂ O _2的不可逆氧化和还原波。铂黑表面的氧还原反应（ORR）仅产生H ₂ O ₂（2个电子/ 2 H ⁺）在生理pH下。因此，Pt黑UME可以感应出不同的ROS，包括超氧阴离子，以供将来进行生物医学或理化研究。