Here we develop a simple and effective nose/tongue sensor array based on Co-N-C single-atom nanozymes-3,3′,5,5′-tetramethylbenzidine (TMB)-H₂O₂ for colorimetric discrimination of antioxidants, which makes use of the color reaction of TMB oxidation by H₂O₂ in two different pH (3.8 and 4.6) environments under the catalysis of Co-N-C nanoenzyme with peroxidase-like activity. Different antioxidants have varying reducing ability to the oxidation products of TMB (oxTMB), thus resulting in differential absorbance and color changes. Linear discriminant analysis (LDA) results indicate that the sensor array successfully identified 7 antioxidants, i.e., glutathione (GSH), ascorbic acid (AA), cysteine (Cys), tannin (TA), Catechin (C), dopamine (DA), and uric acid (UA) in both buffer and even serum samples. Additionally, the performance of the sensor array was validated with antioxidant mixtures, individual antioxidants with different concentrations, and target antioxidants and interfering substances. In general, the versatile sensor array based on Co-N-C single-atom nanozymes provides an excellent strategy for identifying a variety of antioxidants, which exhibits a broad application prospect in medical diagnosis.

在这里，我们开发了一种基于 Co-NC 单原子纳米酶-3,3',5,5'-四甲基联苯胺 (TMB)-H ₂ O ₂的简单有效的鼻子/舌头传感器阵列，用于比色区分抗氧化剂，这使得使用H ₂ O ₂氧化TMB的显色反应在具有类过氧化物酶活性的 Co-NC 纳米酶的催化下，在两种不同的 pH（3.8 和 4.6）环境中。不同的抗氧化剂对TMB（oxTMB）的氧化产物具有不同的还原能力，从而导致不同的吸光度和颜色变化。线性判别分析（LDA）结果表明，传感器阵列成功识别了7种抗氧化剂，即谷胱甘肽（GSH）、抗坏血酸（AA）、半胱氨酸（Cys）、单宁（TA）、儿茶素（C）、多巴胺（DA）、缓冲液甚至血清样品中的尿酸 (UA)。此外，传感器阵列的性能通过抗氧化剂混合物、不同浓度的单个抗氧化剂以及目标抗氧化剂和干扰物质进行了验证。一般来说，