Facile synthesis of soybean phospholipid-encapsulated MoS₂ nanosheets for efficient in vitro and in vivo photothermal regression of breast tumor

Abstract

Two-dimensional MoS₂ nanosheet has been extensively explored as a photothermal agent for tumor regression; however, its surface modification remains a great challenge. Herein, as an alternative to surface polyethylene glycol modification (PEGylation), a facile approach based on “thin-film” strategy has been proposed for the first time to produce soybean phospholipid-encapsulated MoS₂ (SP-MoS₂) nanosheets. By simply vacuum-treating MoS₂ nanosheets/soybean phospholipid/chloroform dispersion in a rotary evaporator, SP-MoS₂ nanosheet was successfully constructed. Owing to the steric hindrance of polymer chains, the surface-coated soybean phospholipid endowed MoS₂ nanosheets with excellent colloidal stability. Without showing detectable in vitro and in vivo hemolysis, coagulation, and cyto-/histotoxicity, the constructed SP-MoS₂ nanosheets showed good photothermal conversion performance and photothermal stability. SP-MoS₂ nanosheet was shown to be a promising platform for in vitro and in vivo breast tumor photothermal therapy. The produced SP-MoS₂ nanosheets featured low cost, simple fabrication, and good in vivo hemo-/histocompatibility and hold promising potential for future clinical tumor therapy.

Keywords:

• soybean phospholipid
• MoS₂ nanosheets
• in vivo
• photothermal regression
• breast tumor

Supplementary materials

Figure S1 TEM image of MoS₂ nanosheets.

Abbreviation: TEM, transmission electron microscope.

Figure S2 DLS diameters of SP-Mos2 nanosheets.

Notes: DLS diameters of SP-MoS₂ nanosheets in (A) water, (B) saline, and (C) RPMI-1640 medium before (blue) and after (green) 2 days.

Abbreviations: DLS, dynamic light scattering; SP-MoS₂, soybean phospholipid-encapsulated MoS₂; RPMI-1640, Roswell Park Memorial Institute-1640.

Figure S3 DLS diameters of pure MoS₂ nanosheets in saline before and after 24 hours.

Abbreviations: DLS, dynamic light scattering; h, hours.

Figure S4 Cell viability assay of L929 cells after treatment with pure MoS₂ nanosheets at given Mo concentrations for 24 hours (mean ± SD, n=3).

Abbreviation: SD, standard deviation.

Figure S5 Temperature variations of SP-MoS₂ dispersion ([Mo] =100 ppm) under five cycles of continuous NIR irradiation (1.0 W/cm²

Abbreviations: SP-MoS₂, soybean phospholipid-encapsulated MoS₂; NIR, near-infrared; T, temperature.

Figure S6 In vivo thermal images of mice injected with saline IV.

Notes: (A–D) Mouse was irradiated with NIR for 5 minutes, and the images were captured at different time points.

Abbreviations: IV, intravenous; NIR, near-infrared; s, seconds.

Figure S7 The survival rates of mice after different treatments.

Abbreviations: IV, intravenous; IT, intratumoral.

Figure S8 Biodistribution of Mo in major organs at different time points post IV injection (mean ± SD, n=3).

Abbreviations: IV, intravenous; SD, standard deviation; h, hours.

Acknowledgments

This work was sponsored by “Chenguang Program” supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission (14CGB15 for YG, and 15CG52 for SW). The authors also thank the State Key Laboratory of Molecular Engineering of Polymers (K2016-20, Fudan University) for their support.

Disclosure

The authors report no conflicts of interest in this work.