Chitosan-modified magnetic graphene oxide nanoassembly: a dual-functional platform for targeted protein adsorption and natural bioactive ingredient screening.

Although natural products constitute one of the crucial sources for drug development and new drug research, the traditional screening methods are often time-consuming and exhibit low accuracy. To address this issue, a more efficient and precise ligand fishing-bound high resolution mass spectrometry coupled molecular dynamics technology is employed. This study introduces a chitosan-modified magnetic graphene oxide composite (MGO/CS) that enhances ligand fishing through superior protein binding capacity. The results revealed that MGO/CS manifested considerable loading capacity and stability, the loading capacity of MGO/CS can reach 1.5 times that of GO. Moreover, compared with MGO, MGO/CS exhibits a protein immobilization rate that is 20 % higher. Additionally, CMP@MGO/CS still sustained a constant loading rate of 70 % after 7 days at 4 °C. Subsequently, high-performance liquid chromatography-hybrid linear ion trap/orbitrap mass spectrometry was utilized to screen the potential active substances binding to fibrotic VEGFR-2 protein in Cordyceps sinensis. To verify the accuracy of the screening of the compounds binding to VEGFR-2 protein, molecular docking simulation and biological validation were conducted. Functional assays demonstrated that inosine and uridine significantly reversed TGF-β1-induced mesenchymal-like morphological alterations in pulmonary fibrosis models, as evidenced by quantitative restoration of epithelial cobblestone morphology. This research offers an efficient, efficacious and convenient approach for the discovery of active ingredients in natural products.