Microwave-assisted preparation of paramagnetic zwitterionic amphiphilic copolymer hybrid molybdenum disulfide for T1-weighted magnetic resonance imaging-guided photothermal therapy

Abstract

Magnetic resonance imaging (MRI)-guided photothermal therapy (PTT) has recently attracted tremendous attention. In this study, a paramagnetic zwitterionic amphiphilic copolymer (PZAC) was successfully prepared and utilized as a multifunctional surfactant to form micelles in diethylene glycol to coordinate with a molybdenum disulfide precursor (MoS₂). Uniform spherical MoS₂ nanohybrids (MoS₂@PZAC) were first prepared by a microwave-assisted solvothermal process, which is simpler, easier and more efficient than hydrothermal methods or exfoliation processes. In this nanoplatform, MoS₂ serves as a phototherapeutic agent possessing a high photothermal conversion efficiency (33.8%), while PZAC acts as a T₁-weighted MRI contrast agent. This nanoplatform has the advantages of ultralow toxicity, prolonged circulation time and bio-imaging guided capability. The cytotoxicity assessment showed the good cytocompatibility of MoS₂@PZAC. Furthermore, MoS₂@PZAC could effectively kill cancer cells upon 2 W cm⁻² 808 nm laser irradiation for 10 min in both in vitro and in vivo experiments. This work provides a novel and efficient solution to synthesize a multifunctional and uniform theranostic agent, and the results show that the as-prepared MoS₂@PZAC can be used as a promising theranostic agent for T₁-weighted MRI-guided PTT of cancer cells.