Ma Yu, Xu Maotian, Wang Yongxiang, Liu Zi, Ye Baoxian
Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou, 450001, China.
Henan Key Laboratory of Biomolecular Recognition and Sensing, Henan Joint International Research Laboratory of Chemo/Biosensing and Early Diagnosis of Major Diseases, School of Chemistry and Chemical Engineering, Shangqiu Normal University, Shangqiu, 476000, China.
Analyst. 2020 Apr 14;145(8):2995-3001. doi: 10.1039/d0an00093k.
This work reports the first example of a colorimetric H2S sensor constructed through G-quadruplex-Cu2+ (G4-Cu2+) peroxidase mimetics employing Cu2+ ions and G-rich DNA with signal amplification. In the hydrogen peroxide (H2O2)-mediated oxidation of 3,3',5,5'-tetramethylbenzidine (TMB), the catalytic capacity of Cu2+ can be greatly improved in the presence of 22AG DNA, where 22AG DNA acts as a signal amplifier. However, G4-Cu2+ peroxidase mimetics lose their catalytic abilities after reacting with H2S. This is employed to develop a colorimetric assay of H2S without complex synthesis and instrumentation, with a linear range from 0.01 μM to 150 μM and a detection limit of 7.5 nM. The sensitivity of the sensor can also be adjusted by changing the concentration of Cu2+. Moreover, the developed sensor is successfully applied for the quantitative determination of H2S in human serum samples.
这项工作报道了首个通过采用铜离子和富含鸟嘌呤的DNA构建的具有信号放大功能的G-四链体-铜离子（G4-Cu2+）模拟过氧化物酶的比色法硫化氢传感器。在过氧化氢（H2O2）介导的3,3',5,5'-四甲基联苯胺（TMB）氧化反应中，在22AG DNA存在的情况下，铜离子的催化能力可得到极大提高，其中22AG DNA作为信号放大器。然而，G4-Cu2+模拟过氧化物酶与硫化氢反应后会失去其催化能力。利用这一点开发了一种无需复杂合成和仪器设备的硫化氢比色测定法，线性范围为0.01 μM至150 μM，检测限为7.5 nM。还可通过改变铜离子浓度来调节传感器的灵敏度。此外，所开发的传感器成功应用于人血清样品中硫化氢的定量测定。
