One-Step Fabrication of Multifunctional PLGA-HMME-DTX@MnO₂ Nanoparticles for Enhanced Chemo-Sonodynamic Antitumor Treatment

Figures & data

Scheme 1 Schematic illustration of one-step fabrication of PLGA-HMME-DTX@MnO₂ nanoparticle via flash nanoprecipitation method.

Abbreviations: FNP, flash nanoprecipitation; PLGA, poly(lactic-co-glycolic acid); ACN, acetonitrile; PVA, polyvinyl alcohol; MES, morpholineethanesulfonic acid; SDS, sodium dodecyl sulphate; DTX, docetaxel; HMME, hematoporphyrin monomethyl ether.

Table 1 Grouping and treatment in vivo

No.	Group Name	Agents	Treatment (Ultrasound Irradiation)
1	Control	200 μL Saline	No
2	US	200 μL Saline	Yes
3	HMME+US	HMME, 320 μg/mL, 200 μL	Yes
4	PH+US	PH, 320 μg/mL (HMME portion), 200 μL	Yes
5	PHD	PHD, 320 μg/mL (HMME portion), 200 μL	No
6	PHD+US	PHD, 320 μg/mL (HMME portion), 200 μL	Yes
7	PHD@MnO2+US	PHD@MnO2, 320 μg/mL (HMME portion), 200 μL	Yes

Figure 1 In vitro assessment of therapeutic efficacy. (A) Schematic illustration of the therapeutic process. (B) Bodyweight curves and (C) tumor growth curves of mice in different groups (*p<0.05, **p<0.01). (D) Photos of tumors collected from different groups. (E) Expression levels of HIF-1α in tumor tissues. (F) H&E staining of tumors in different groups after various treatments.

Abbreviations: HIF-1α, hypoxia inducible factor 1α; H&E staining, hematoxylin-eosin staining.

Figure 2 Preparation and characterization of nanoparticles. (A) Photo of (a) PLGA, (b) PLGA-HMME (c) PLGA-HMME-DTX and (d) PLGA-HMME-DTX@MnO₂ nanoparticles in buffer. (B) Zeta-potential of four nanoparticles. (C) PLGA-HMME-DTX@MnO₂ nanoparticle after lyophilization. (D) TME images of PLGA-HMME-DTX@MnO₂ nanoparticles (The black scale bars represent 100 nm). (E) Particle-size distribution of PLGA-HMME-DTX@MnO_2.

Abbreviations: TME, transmission electronic microscopy; PLGA, poly(lactic-co-glycolic acid); HMME, hematoporphyrin monomethyl ether; DTX, docetaxel.

Figure 3 (A) Fluorescence emission spectrum of HMME and PHD@MnO₂. (B) XPS spectrum of PLGA-HMME-DTX@MnO₂ nanoparticle. (C) FT-IR infrared spectra of MnO₂ and PLGA-HMME-DTX@MnO₂ nanoparticle. (D) Ultrasound-irradiated singlet oxygen generation in vitro. (E) Ultrasound-irradiated hydroxy radical generation in vitro. (F) Cumulative release curves of PLGA-HMME-DTX@MnO₂ with or without ultrasound in different conditions (pH= 7.4 and 5.3).

Abbreviations: XPS, X-ray photoelectron spectroscopy; FT-IR, Fourier transform infrared spectroscopy.

Figure 4 (A) cellular uptake of PLGA-HMME-DTX@MnO₂ into MCF-7 cells. The white scale bars represent 25 μm. (B) MCF-7 cell viability under different treatments. (C) The intracellular GSH concentration under the treatment of nanoparticles with MnO₂. (*p<0.05, **p<0.01).

Abbreviation: GSH, glutathione.

Figure 5 Cellular ROS generation in MCF-7 cells. (A) Microscopy images of intracellular ROS generation by DCFH-DA. The white scale bars represent 25 μm. (B) Mean optical density of green fluorescence in different groups quantified by ImageJ software.

Abbreviations: ROS, reactive oxygen species; DCFH-DA, 2.7, -dichlorofluorescein diacetate.

Figure 6 In vitro biodistribution and biocompatibility. (A) Fluorescence images of isolated organs and tumors at different time point after HMME injection. (B) Fluorescence images of isolated organs and tumors at different time point after PLGA-HMME-DTX@MnO₂ injection. (C) H&E staining sections of organs after PLGA-HMME-DTX@MnO₂ treatment.