Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.
Key Laboratory of Interfacial Reaction & Sensing Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.
Biosens Bioelectron. 2018 May 30;106:14-20. doi: 10.1016/j.bios.2018.01.050.
A novel label-free photoelectrochemical (PEC) sensor based on graphene quantum dots doped with nitrogen and sulfur (N,S-GQDs) and CdS co-sensitized hierarchical ZnSnO cube was fabricated to detect cardiac troponin I (cTnI). The unique hierarchical ZnSnO cube was synthesized successfully by the solvothermal method, which has a large specific surface to load functional materials. N,S-GQDs nanoparticles were assembled to the surface of cubic ZnSnO coated ITO electrode, which efficiently accelerated the electronic transition and improved photo-to-current conversion efficiency. Then, CdS nanoparticles further were modified by in-situ growth method to form ZnSnO/N,S-GQDs/CdS composite with prominent photocurrent, which was 30 times that of the ZnSnO cube alone. In this work, the specific immune recognition between cTnI antigens and cTnI antibodies (anti-cTnI) reduced the intensity of the photoelectric signal. And the intensity decreased linearly with the logarithm of cTnI concentration range from 0.001 ng/mL to 50 ng/mL with a detection limit of 0.3 pg/mL. With high sensitivity, excellent selectivity, good stability and reproducibility, the fabricated PEC sensor showed promising applications in the sensor, clinical diagnosis of myocardial infarction and PEC analysis.
一种基于氮硫共掺杂石墨烯量子点（N,S-GQDs）和共敏化分级 ZnSnO 立方体的 CdS 的新型无标记光电化学（PEC）传感器被制备用于检测心肌肌钙蛋白 I（cTnI）。独特的分级 ZnSnO 立方体通过溶剂热法成功合成，具有较大的比表面积来负载功能材料。N,S-GQDs 纳米粒子被组装到涂覆 ITO 电极的立方 ZnSnO 表面，这有效地加速了电子跃迁并提高了光电电流转换效率。然后，通过原位生长法进一步修饰 CdS 纳米颗粒，形成具有突出光电流的 ZnSnO/N,S-GQDs/CdS 复合材料，其光电流是单独的 ZnSnO 立方体的 30 倍。在这项工作中，cTnI 抗原和 cTnI 抗体（抗 cTnI）之间的特异性免疫识别降低了光电信号的强度。光电信号的强度随 cTnI 浓度从 0.001ng/mL 到 50ng/mL 的对数线性降低，检测限为 0.3pg/mL。所制备的 PEC 传感器具有高灵敏度、优异的选择性、良好的稳定性和重现性，在传感器、心肌梗死的临床诊断和 PEC 分析方面显示出有前景的应用。
