Magnetic covalent organic framework nanospheres-based miRNA biosensor for sensitive glioma detection

Sensitive detection and accurate diagnosis/prognosis of glioma remain urgent challenges. Herein, dispersed magnetic covalent organic framework nanospheres (MCOF) with uniformed Fe3O4 nano-assembly as cores and high-crystalline COF as shells were prepared by monomer-mediated in-situ interface growth strategy. Based on the unique interaction between MCOF and hairpin DNA, a fluorescent signal amplified miRNA biosensor was constructed. It could realize the sensitive detection of miRNA-182 in different matrixes, where the detection limit, linearity range and determination coefficient (R2) in real blood samples reached 20 fM, 0.1 pM–10 pM and 0.991, respectively. Also, it possessed good stability and precision as observed from the low intra-day/inter-day RSD and high extraction recovery. As a result, it could quantify miRNA-182 in serum of glioma patients, the concentration of which was significantly higher than that of healthy people and obviously decreased after surgery. Finally, a proof-of-concept capillary chip system using this biosensor was proposed to realize the visualized detection of miRNA-182 in microsample. These findings suggest a robust way for sensitive detection and accurate diagnosis/prognosis of glioma. [Display omitted] •Magnetic COF nanospheres (MCOF) with uniformed size and high crystallinity were prepared by in-situ interface growth.•A fluorescent signal amplified miRNA biosensor was developed based on the MCOF-mediated isothermal hybrid chain reaction.•MCOF-based biosensor could achieve the sensitive miRNA-182 detection in different matrixes.•Accurate diagnosis/prognosis of glioma patients before and after surgery could be achieved.•A proof-of-concept capillary chip was proposed for the visualized detection of miRNA-182 in microsample.