The relative length of dual-target conjugated on iron oxide nanoparticles plays a role in brain glioma targeting

The application of superparamagnetic iron oxide nanoparticles as a magnetic resonance (MR) nanoprobe for brain glioma is limited by the insufficient specificity and accumulation at the tumor site. To increase brain glioma-targeting specificity and improve MR contrast effect, dual-target has been employed. However, up to now, little work has been done to ascertain if the relative length of the dual-target plays a role in targeting. Herein, we prepared Cy5.5-labeled Fe3O4 NPs with chlorotoxin (CTX)/PEGylated folic acid (PEG-FA) dual-target of different relative lengths. The effect of dual-target relative length on targeting specificity was investigated by in vitro cellular uptake and in vivo MR/NIR imaging in brain glioma-bearing mice. It was demonstrated that the targeting ability of the dual-targeting Fe3O4 NPs could be modulated by adjusting the relative length of dual-target, suggesting that the relative length of dual-target plays a role in brain glioma targeting.