All-in-One Nanohybrids Combining Sonodynamic Photodynamic and Photothermal Therapies

Abstract

A wide variety of methods are being developed to ultimately defeat cancer; while some of these strategies have shown highly positive results, there are serious obstacles to overcome to completely eradicate this disease. So, it is crucial to construct multifunctional nanostructures possessing intelligent capabilities that can be utilized to treat cancer. A possible strategy for producing these multifunctional nanostructures is to combine various cancer treatment techniques. Based on this point of view, we successfully synthesized multifunctional HCuS@Cu₂S@Au-P(NIPAM-co-AAm)-PpIX nanohybrids. The peculiarities of these thermosensitive polymer-modified and protoporphyrin IX (PpIX)-loaded hollow nanohybrids are that they combine photodynamic therapy (PDT), sonodynamic therapy (SDT), and photothermal therapy (PTT) with an intelligent design. As an all-in-one nanohybrids, HCuS@Cu₂S@Au-P(NIPAM-co-AAm)-PpIX nanohybrids were employed in the SDT-PDT-PTT combination therapy, which proved to have a synergistic therapeutic effect for in vitro tumor treatments against breast tumors.

Keywords: hollow nanohybrids; photodynamic therapy; photothermal therapy; sonodynamic therapy; thermosensitive polymer.

Scheme 1. Schematic Illustration of the Synthesis Procedures and SDT–PDT–PTT Triple Therapy Effect

Figure 1

SEM images of HCuS (A), HCuS@Cu₂S@Au (B,C), EDS elemental mapping (D), and EDS characterization of HCuS@Cu₂S@Au (E).

Figure 2

XPS high-resolution scans of Cu 2p peaks in HCuS (A) and HCuS@Cu₂S@Au (B). Detailed spectra of Cu 2p_3/2 in HCuS@Cu₂S@Au (C). XPS high-resolution scans of Au 4f in HCuS@Cu₂S@Au (D) and Auger electron spectrum of HCuS@Cu₂S@Au CuLM2 (E). XRD patterns of CuS and CuS@Au (F).

Figure 3

LCST measurement of P(NIPAM-co-AAm) copolymer’s aqueous solution (A) and LCST behavior of P(NIPAM-co-AAm) in aqueous solution (B). (a) below the cloud point and (b) above the cloud point, the solution became turbid.

Figure 4

SEM images of HCuS@Cu₂S@Au–P(NIPAM-co-AAm) (A,B) and HCuS@Cu₂S@Au–P(NIPAM-co-AAm)-PpIX (C,D). All scale bars are 1 μm. FTIR spectra of HCuS, HCuS@Cu₂S@Au, P(NIPAM-co-AAm), and HCuS@Cu₂S@Au–P(NIPAM-co-AAm) (E) and zeta potentials of HCuS, HCuS@Cu₂S@Au, HCuS@Cu₂S@Au–P(NIPAM-co-AAm), and HCuS@Cu₂S@Au–P(NIPAM-co-AAm)-PpIX (F).

Figure 5

Decrease in the absorbance of DPBF in the presence of 0.8 mg/mL of hybrid nanoparticles at 416 nm in PBS/DMSO after irradiation with a 630 nm LED (A). Decrease in the absorbance of DPBF in the presence of 0.8 mg/mL of hybrid nanoparticles at 416 nm in PBS/DMSO after irradiation with 808 nm (1.5 W/cm²) laser (B). Decrease in the absorbance of DPBF in the presence of 0.8 mg/mL of hybrid nanoparticles at 416 nm in PBS/DMSO after irradiation with 3 MHz US (C). Insets: graphs showing the decrease in the maximum absorbance of DPBF at 416 nm over time in the presence of 0.8 mg/mL of hybrid nanoparticles.

Figure 6

Temperature increases of HCuS@Cu₂S@Au–P(NIPAM-co-AAm)-PpIX nanohybrids at different concentrations in PBS after irradiation with an 808 nm (1.5 W/cm²) laser for various times. Inset: thermal camera images of different concentrations of HCuS@Cu₂S@Au–P(NIPAM-co-AAm)-PpIX nanohybrids after irradiation with the 808 nm (1.5 W/cm²) laser for 450 s.

Figure 7

Temperature increases of PBS, HCuS, HCuS@Cu₂S@Au, HCuS@Cu₂S@Au–P(NIPAM-co-AAm), and HCuS@Cu₂S@Au–P(NIPAM-co-AAm)-PpIX nanohybrids at same concentrations (1.5 mg/mL) after irradiation with an 808 nm (1.5 W/cm²) laser for various times. Inset: thermal camera image of nanostructures after laser irradiation for 450 s. (A). Temperature increases of PBS, HCuS, HCuS@Cu₂S@Au, HCuS@Cu₂S@Au–P(NIPAM-co-AAm), and HCuS@Cu₂S@Au–P(NIPAM-co-AAm)-PpIX nanohybrids (B).

Figure 8

Decrease in the absorbance of DPBF in the presence of 0.8 mg/mL of hybrid nanoparticles at 416 nm in PBS/DMSO after irradiation with 3 MHz US + 630 nm LED + 808 nm (1.5 W/cm²) laser (A). The decrease in the maximum absorbance of DPBF at 416 nm over time in the presence of 0.8 mg/mL of hybrid nanoparticles (B).

Figure 9

Decrease in the absorbance of DPBF in the presence of 0.8 mg/mL of HCuS (A), HCuS@Cu₂S@Au (B), HCuS@Cu₂S@Au–P(NIPAM-co-AAm) nanoparticles (C), and PpIX (D) at 416 nm in PBS/DMSO after irradiation with 3 MHz US + 630 nm LED + 808 nm (1.5 W/cm²) laser. Insets: graphs show the decrease in the maximum absorbance of DPBF at 416 nm over time in the presence of 0.8 mg/mL of nanoparticles or PpIX.

Figure 10

Decrease in the absorbance of DPBF in the presence of 0.8 mg/mL of hybrid nanoparticles at 416 nm in PBS/DMSO after irradiation with 3 MHz US + 630 nm LED (A), 630 nm LED + 808 nm (1.5 W/cm²) laser (B), and 3 MHz US + 808 nm (1.5 W/cm²) laser (C). Insets: the decrease in the absorbance of DPBF in the presence of 0.8 mg/mL of hybrid nanoparticles at 416 nm over times.

Figure 11

Concentration-dependent proliferation inhibition of MDA-MB-231 cells treated with HCuS, HCuS@Cu₂S@Au, HCuS@Cu₂S@Au-(P(NIPAM-co-AAm)), PpIX, and HCuS@Cu₂S@Au-(P(NIPAM-co-AAm))-PpIX nanohybrids only. Cell viability was evaluated using the XTT test, and the results are presented as mean ± SD in triplicate (A). Concentration-dependent proliferation inhibition of MDA-MB-231 cells treated with HCuS, HCuS@Cu₂S@Au, HCuS@Cu₂S@Au-(P(NIPAM-co-AAm)), PpIX, and HCuS@Cu₂S@Au-(P(NIPAM-co-AAm))-PpIX nanohybrids after exposure to LED+US+laser. Cell viability was evaluated using the XTT test, and the results are presented as mean ± SD in triplicate (B).

Figure 12

Concentration-dependent proliferation inhibition of MDA-MB-231 cells treated with PpIX and HCuS@Cu₂S@Au-(P(NIPAM-co-AAm))-PpIX nanohybrids only and after exposure to laser, LED, US, or their combinations. Cell viability was evaluated using the XTT test and the results are presented as mean ± SD in triplicate.

Figure 13

Fluorescence microscopic images of TUNEL staining of MDA-MB-231 cells treated with different concentrations of HCuS, HCuS@Cu₂S@Au, PpIX, HCuS@Cu₂S@Au–P(NIPAM-co-AAm), and HCuS@Cu₂S@Au–P(NIPAM-co-AAm)-PpIX, and exposed to US (3 MHz), LED (690 nm), laser (808 nm, 1 W/cm²), US+LED, US+laser, LED+laser, and US+LED+laser.