Two-dimensional oriented growth of Zn-MOF-on-Zr-MOF architecture: A highly sensitive and selective platform for detecting cancer markers

• Published in: Biosensors & bioelectronics Vol. 123; pp. 51 - 58
• Main Authors: Zhou, Nan, Su, Fangfang, Guo, Chuanpan, He, Linghao, Jia, Zhankui, Wang, Minghua, Jia, Qiaojuan, Zhang, Zhihong, Lu, Siyu
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 01-01-2019
• Subjects: Bimetallic ZnZr-metal organic frameworks; Biomarkers, Tumor - genetics; Biomarkers, Tumor - isolation & purification; Biosensing Techniques; Cell Adhesion Molecules - chemistry; Cell Adhesion Molecules - genetics; Cell Adhesion Molecules - isolation & purification; Detection of protein tyrosine kinase-7; Electrochemical aptasensor; Humans; Limit of Detection; Metal-Organic Frameworks - chemistry; MOF-on-MOF hybrids; Neoplasms - diagnosis; Neoplasms - genetics; Receptor Protein-Tyrosine Kinases - genetics; Receptor Protein-Tyrosine Kinases - isolation & purification; Zinc - chemistry; Zirconium - chemistry; Bimetallic ZnZr-metal organic frameworks; MOF-on-MOF hybrids; Detection of protein tyrosine kinase-7; Electrochemical aptasensor
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2018.09.079

Fabricating novel bimetallic metal organic framework (MOF) architectures and exploiting them as aptasensor scaffolds for detecting diverse analytes, especially cancer markers, have aroused widespread research attention. Herein, we report a novel strategy for obtaining ZnZr bimetallic MOFs via the MOF-on-MOF method and exploit them as an aptasensor platform for detecting the cancer marker protein tyrosine kinase-7 (PTK7). Basic characterizations reveal that the chemical structure, crystalline properties, and surface functionality of bimetallic ZnZr-MOFs can be modulated by changing the order of addition of metal precursors and organic ligands. The Zn-MOF-on-Zr-MOF hybrid exhibits a hierarchically decussated foliace, whereas Zr-MOF-on-Zn-MOF demonstrates a multilayered nanosheet structure. The electrochemical results reveal that Zr-MOF facilitates aptamer strand immobilization, whereas the Zn-MOF stabilizes the G-quadruplex formed by aptamer strands and PTK7. The Zn-MOF-on-Zr-MOF-based aptasensor outperforms the Zr-MOF-on-Zn-MOF-based one, providing ultralow detection limits of 0.84 and 0.66 pg mL−1, as obtained by electrochemical impedance spectroscopy and differential pulse voltammetry, respectively, within the PTK7 concentration range of 1.0 pg mL−1 to 1.0 ng mL−1. The proposed Zn-MOF-on-Zr-MOF-based aptasensor exhibits high selectivity in the presence of various interferences, good stability, reproducibility, and acceptability in human serum. The proposed strategy provides a new approach for fabricating ultrasensitive and selective bimetallic MOFs-based aptasensors and contributes to efforts to broaden their applications in early cancer diagnosis.
•A novel ZnZr bimetallic MOFs prepared by the method of MOF-on-MOF.•Zn-MOF-on-Zr-MOF exhibits the hierarchically decussated foliace.•Zr-MOF-on-Zn-MOF is the multilayered nanosheets structure.•The Zn-MOF-on-Zr-MOF-based aptasensor possesses outstanding sensing performances toward PTK7.