Multicomponent zirconium-based metal-organic frameworks for impedimetric aptasensing of living cancer cells

• Published in: Sensors and actuators. B, Chemical Chemical, 2020-03, Vol.306, p.127608, Article 127608
• Main Authors: Li, Yu, Hu, Mengyao, Huang, Xiaoyu, Wang, Minghua, He, Linghao, Song, Yingpan, Jia, Qiaojuan, Zhou, Nan, Zhang, Zhihong, Du, Miao
• Format: Article
• Language: English
• Subjects: Aqueous solutions; Cancer; Complexity; Covalent bonds; Detection of living cancer cells; Electrochemical biosensor; Metal-organic frameworks; Multicomponent organic framework; Phosphate group-modified aptamer; Zirconium; Zr-based metal-organic framework
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2019.127608

Three types of zirconium-based metal-organic frameworks were synthesized and developed as novel bio-platforms to anchor phosphate group-modified aptamer (PO4-Apt) and sensitively detect living Michigan cancer foundation-7 (MCF-7) cancer cells. The UiO-66-2NH2-based aptasensor exhibited highly significant biosensing to detect MCF-7 cells and showed extremely low detection limit of 31 cell mL−1, as well as high specificity, good stability, and outstanding reproducibility. [Display omitted] •Zr-MOFs with amino-functionalization were explored as platforms for detecting living MCF-7 cancer cells.•Phosphate group modified aptamer strands can form strong covalent bond with Zr-atom centers.•Promoted aptamer immobilization; the superior sensing performance.•An extremely low detection limit of 31 cell mL−1. We have synthesized a series of zirconium-based metal-organic frameworks (Zr-MOFs) using 1,4-dicarbxybenzene (DB), 2-aminoterephthalic acid (AA), and the mixture of AA and 2,5-diaminoterephthalic acid (DA) as ligands (represented by UiO-66, UiO-66-NH2, and UiO-66-2NH2, respectively) and developed them as platforms to anchor phosphate group-modified aptamer (PO4-Apt) and sensitively detect living Michigan cancer foundation-7 (MCF-7) cancer cells. The diversity, complexity, and amino-functionality of UiO-66-2NH2 were increased, but retained the nature of the pristine UiO-66. Compared with UiO-66 and UiO-66-NH2, the multicomponent UiO-66-2NH2 exhibited significant electrochemical activity and stronger bio-affinity toward PO4-Apt via the π−π∗ stacking, electrostatic interaction, and covalently bonds of Zr-O-P. These merits of UiO-66-2NH2 endowed the corresponding aptasensor with high ability to stabilize the formed aptamer-cells complex in aqueous solution. Meanwhile, compared with the label-free immobilized aptamer, PO4-Apt can form strong covalent bond with Zr-atom centers, thus promoting aptamer immobilization and boosting the sensing performance. The developed UiO-66-2NH2-based aptasensor displayed highly significant biosensing to detect MCF-7 cells and showed extremely low detection limit of 31 cell mL−1 in a wide linear range from 100 to 100,000 cell mL−1, as well as high specificity, good stability, and outstanding reproducibility. The present work studied the modulated sensing ability of the multicomponent MOFs for living cancer cells and provided alternative approach for the early diagnosis of cancer.