点击次数：

论文类型：期刊论文

发表时间：2019-05-15

发表刊物：ACS APPLIED MATERIALS & INTERFACES

收录刊物：PubMed、SCIE、EI

卷号：11

期号：19

页面范围：17467-17474

ISSN号：1944-8244

关键字：g-C3N4; nanoneedles; peroxidase-like; DNA; biosensor

摘要：Graphitic carbon nitride (g-C3N4) as a metal-free nanozyme has attracted huge attention for catalytic applications. However, the catalytic activity of pure g-C3N4 causes very moderate H2O2 activation. Herein, a novel three-dimensional (3D) branched carbon nitride nanoneedle (3DBC-C3N4) nanozyme has been proposed to overcome such shortcoming. This unique 3D branched structure of 3DBC-C3N4 facilitated effective mass transfer during catalytic reaction and induced a lightning rodlike effect to accelerate electron collection at the tip area for H2O2 activation. With improved H2O2 activation for hydroxyl radical ((OH)-O-center dot) generation, 3DBC-C3N4 showed excellent peroxidase-like activity toward 3,3',5,5'-tetramethylbenzidine oxidation in the presence of H2O2. As for H2O2, the V-max value of 3DBC-C3N4 was found to be 20 times higher than that of natural horseradish peroxidase. Moreover, the 3D branched structure of 3DBC-C3N4 offered large interface for the reversible conjugation of single-stranded DNA, which enhanced the colorimetric sensitivity. Moreover, 3DBC-C3N4 exhibited high sensitivity toward oxytetracycline detection, with the detection limit and quantitative limit of 1 and 50 mu g/L, respectively.