Peptide-functionalized NaGdF₄ Nanoparticles For Breast Tumor-targeted Magnetic Resonance Imaging And Effective Therapy

Objective:To investigate the feasibility of peptide-functionalized NaGdF₄ nanoprobes for targeted magnetic resonance imaging and treatment in breast cancer-bearing mice.Method:With NaGdF4 nanodots as the core,oleic acid-encapsulated nanodots are linked to peptides with targeted therapeutic function by ligand exchange method,and a new type of targeted MRI nanoprobe NaGdF₄@bp-peptide NPs with integrated diagnosis and treatment is constructed to evaluate its biocompatibility.In a breast cancer-bearing mouse model,magnetic resonance imaging?MRI?and targeted therapy experiments were performed,the results of MRI images were analyzed,tumor growth curves were plotted,and the effects of targeted therapy were evaluated.Results:The in vivo and in vitro toxicity experiments show that the constructed MRI nanoprobe NaGdF₄@bp-peptide NPs have good biocompatibility.The MRI images of the MCF-7 tumor-bearing Balb / c nude mice showed that the contrast enhancement of MR at the tumor site was significantly increased within 0 to 24 hours after tail vein injection of NaGdF₄@bp-peptide NPs,and reached a maximum at 1 h after injection.MR signal strength?3.25 times?.NaGdF₄@CPP NPs showed a relatively low degree of MR enhancement at the tumor site.The results of targeted therapy experiments showed that mice injected with NaGdF₄@bp-peptide NPs particles showed a delay in tumor growth compared to mice injected with PBS solution and mice injected with NaGdF₄@CPP NPs particles,suggesting NaGdF₄@bp-peptide NPs have good antitumor biological activity.Conclusion:A strong nano-therapy system?NaGdF₄@bp-peptide NPs?was constructed using the strong interaction between phosphopeptides?bp peptide and CPP?and Gd^{3 +}.In vitro and in vivo experiments show that the prepared NaGdF₄@bp-peptide NPs have good biocompatibility and excellent tumor targeting ability.In addition,in the MCF-7 tumor-bearing Balb / c nude mouse model,MCF-7 tumor-bearing Balb / c nude mice showed good antitumor effects.Due to the multiple biological functions of peptides,this experiment demonstrates the potential of multifunctional nanoparticles as molecular imaging contrast agents and tumor suppressors.