基于Co-N-CDs的MXene纳米复合材料（MXene@PDA/Co-N-CDs）是通过在聚多巴胺功能化的MXene纳米片上修饰Co-N-CDs而构建的。 Co-N-CD 和 MXene 纳米片都具有类似过氧化物酶的活性；当两种材料结合形成MXene@PDA/Co-N-CDs纳米复合材料时，类过氧化物活性可以进一步增强。通过检测蓝色产物的吸收证实，MXene@PDA/Co-N-CDs 可以氧化底物 3,3'5,5'-四甲基联苯胺 (TMB) 形成 ox-TMB。开发了一种高选择性比色生物传感器，用于测定浓度范围为0.3~20 µM的谷胱甘肽（GSH），检测下限（LOD）为0.12 µM，实现了人血清和尿液样本中GSH的准确检测。此外，在肿瘤微环境中，MXene@PDA/Co-N-CDs在NIR-I照射下可以催化过氧化氢产生羟基自由基并产生光热效应。通过光热/光动力协同治疗，充分实现了MXene@PDA/Co-N-CD纳米复合材料对癌细胞死亡的催化活性。 MXene@PDA/Co-N-CDs 纳米酶在 GSH 检测和肿瘤治疗中提供多种应用。

Co-N-CDs-based MXene nanocomposites (MXene@PDA/Co-N-CDs) were constructed by decorating Co-N-CDs on polydopamine-functionalized MXene nanosheets. Both Co-N-CDs and MXene nanosheets have peroxidase-like activity; when the two materials are combined to form MXene@PDA/Co-N-CDs nanocomposites, the peroxide-like activity can be further enhanced. MXene@PDA/Co-N-CDs could oxidize the substrate 3,3'5,5'-tetramethylbenziline (TMB) to form ox-TMB, as confirmed by detecting the absorption of the blue products. A highly selective colorimetric biosensor was developed for the determination of glutathione (GSH) in the concentration range of 0.3 to 20 µM with a lower detection limit (LOD) of 0.12 µM, which realized the accurate detection of GSH in human serum and urine samples. Moreover, in the tumor microenvironment, MXene@PDA/Co-N-CDs could catalyze hydrogen peroxide to produce hydroxyl free radicals and produce a photothermal effect under the exposure of NIR-I irradiation. The catalytic activity of MXene@PDA/Co-N-CD nanocomposites was fully achieved for the death of cancer cells through photothermal/photodynamic synergistic therapy. The MXene@PDA/Co-N-CDs nanozyme offers multiple applications in GSH detection and tumor therapy.