MoS2-based earth-like self-rotating and magnetically navigated nanorobots for magnetic resonance imaging, cancer cell imaging, and therapy

Abstract

Microrobots are poised to revolutionize mass transport systems in emerging biomedical applications, yet their erratic motion poses a significant challenge in controlling their movements, particularly in-vivo. In this study, we introduce highly flexible, self-rotating nanorobots based on MoS2 Nanoflowers (NFs), offering superior control over their movement under magnetic field for cancer cell imaging and therapy. These nanorobots, termed MNBOTs, are constructed by embellishing pre-formed MoS2 NFs with NiFe2O3 nanoparticles (NPs) using polymeric linkers, capitalizing on the abundance of disulfide bonds on the MoS2 surface. In-vitro experiments showcased MNBOT's precise control over velocity, trajectory, and curvature, adapting seamlessly to changes in magnetic flux density under electromagnetic navigation. Moreover, MNBOTs were able to release NiFe2O3 NPs successfully in the tumor environment, facilitated by the collapse of disulfide bonds in the presence of glutathione/dithiothreitol, thus ensuring MNBOT's retrieval post-cancer therapy. Furthermore, we leveraged the photo-heat generation and paramagnetic features of MNBOTs for chemo-photothermal therapy (PTT) and magnetic resonance imaging (MRI) in ex vivo clinical settings. The combined effect of chemotherapy-PTT demonstrated remarkable cytotoxicity against MDA-MB-231 cancer cells, highlighting the synergistic potential of MNBOTs. The integration of diverse functionalities within MNBOTs, including remote magnetic navigation, photothermal therapy, and MRI, presents a versatile platform for addressing pressing healthcare needs, thus holding immense potential for future therapeutic and diagnostic applications. © 2024 Elsevier Ltd