Feng Chang, Chen Yufeng, Wang Weie, Niu Yanan, Cao Xi, Lv Yuguang
School of Chemistry and Chemical Engineering, Mudanjiang Normal University, Mudanjiang 157000, China.
College of Pharmacy, Jiamusi University, Jiamusi 154007, China.
Nanomaterials (Basel). 2025 May 16;15(10):752. doi: 10.3390/nano15100752.
g-CN, a biocompatible material, has prominent applications in biology and is ideal for nano-enzyme studies. Though reported as a peroxidase mimic, its activity remains low. This group combined N,S-doped carbon quantum dots (NS-CQDs) with g-CN (7NSC-g), verifying its peroxidase-like activity. Based on this, a ternary composite of CoO in different forms and 7NSC-g was developed to enhance peroxidase activity, to design a g-CN-based composite enzyme. Characterizations determined the composition and morphology. Colorimetry evaluated peroxidase activity, where the simulated enzyme catalyzes blue product formation from the TMB substrate in the presence of HO. UV-Vis spectrophotometry measured absorbance changes to determine target concentrations. The results show CoO doping improves catalytic activity, with larger specific surface area providing more activation sites. The highest activity of g-CN/NS-CQDs/CoO was at 5% floral CoO, being efficient due to CoO's electron-transfer acceleration and hydroxyl-radical mechanism. Under optimal conditions, the composite detected HO (10.0-230.0 μM, detection limit of 0.031 μM) and glucose (10.0-650.0 μM, detection limit of 1.024 μM).
石墨相氮化碳（g-CN）是一种生物相容性材料，在生物学领域有显著应用，是纳米酶研究的理想材料。尽管它被报道为一种过氧化物酶模拟物，但其活性仍然较低。该团队将氮、硫共掺杂碳量子点（NS-CQDs）与g-CN复合（7NSC-g），验证了其类过氧化物酶活性。在此基础上，开发了不同形态的氧化钴与7NSC-g的三元复合材料，以提高过氧化物酶活性，设计一种基于g-CN的复合酶。表征确定了其组成和形态。比色法评估过氧化物酶活性，其中模拟酶在过氧化氢存在的情况下催化3,3',5,5'-四甲基联苯胺（TMB）底物形成蓝色产物。紫外可见分光光度法测量吸光度变化以确定目标浓度。结果表明，氧化钴掺杂提高了催化活性，更大的比表面积提供了更多的活化位点。g-CN/NS-CQDs/CoO在5%的花状氧化钴时活性最高，由于氧化钴加速电子转移和羟基自由基机制而具有高效性。在最佳条件下，该复合材料可检测过氧化氢（10.0 - 230.0 μM，检测限为0.031 μM）和葡萄糖（10.0 - 650.0 μM，检测限为1.024 μM）。
