Journal: International Journal of Pharmaceutics: X

Article Title: Synergistic photodynamic and chemodynamic therapy using hypoxia-adaptive Ce6@Co nanoparticles for enhanced tumor suppression

doi: 10.1016/j.ijpx.2025.100348

Figure Lengend Snippet: A schematic depicting a hypoxia-adaptive nanoplatform based on Co 2+ -coordinated Ce6 (Ce6@Co) nanoparticles for dual-modal photodynamic and chemodynamic cancer therapy. (a) The hypoxia-adaptive Co 2+ -coordinated Ce6 (Ce6@Co) nanoparticles are constructed by coordinating Co 2+ ions with Ce6 via metal ion coordination and additional π-π stacking interactions. (b) Following intratumoral injection in SCC7 tumor-bearing mice, Ce6@Co nanoparticles distribute throughout the tumor tissue, generating 1 O 2 via Type-II PDT under 670 nm laser irradiation and simultaneously producing cytotoxic ⋅OH via Co 2+ -mediated Fenton-like reactions, even in the hypoxic TME. This amplified dual-ROS generation induces significant apoptosis and results in effective tumor regression.

Article Snippet: Ce6 was procured from Frontier Scientific, Inc. (Logan, UT, USA).

Techniques: Construct, Injection, Irradiation, Amplification

Journal: International Journal of Pharmaceutics: X

Article Title: Synergistic photodynamic and chemodynamic therapy using hypoxia-adaptive Ce6@Co nanoparticles for enhanced tumor suppression

doi: 10.1016/j.ijpx.2025.100348

Figure Lengend Snippet: Ce6@Co nanoparticle characterization. (a) 1 H NMR and (b) Free Ce6 and Ce6@Co nanoparticle FT-IR spectra. (c) Particle size distributions of free Ce6 and Ce6@Co nanoparticles. Inset: Photos of free Ce6 and Ce6@Co nanoparticle solutions in DW before and after sonication. (d) TEM image, elemental mapping of C, O, N, and Co, and EDS spectrum of Ce6@Co nanoparticles. (e) UV/Vis spectra of Ce6 in DMSO and Ce6@Co nanoparticles in DMSO or DW.

Article Snippet: Ce6 was procured from Frontier Scientific, Inc. (Logan, UT, USA).

Techniques: Sonication

Journal: International Journal of Pharmaceutics: X

Article Title: Synergistic photodynamic and chemodynamic therapy using hypoxia-adaptive Ce6@Co nanoparticles for enhanced tumor suppression

doi: 10.1016/j.ijpx.2025.100348

Figure Lengend Snippet: Dual-ROS generation properties of Ce6@Co nanoparticles for singlet oxygen ( 1 O 2 ) generation under laser irradiation (670 nm, 50 mW/cm 2 ) and hydroxyl radical (⋅OH) production via Co 2+ -catalyzed Fenton-like reactions. (a) 1 O 2 generation via free Ce6 (PBS with 1 % Tween 20), Ce6@Co (PBS with 1 % Tween 20), and Ce6@Co (PBS without surfactant). SOSG is highly selective for singlet oxygen forming an endoperoxide anthracene upon reaction, which is no longer an efficient intramolecular electron donor, leading to fluorescence emission at 525 nm. (b) ⋅OH production was assessed under various conditions: TA only, Ce6 + TA, Ce6 + TA + 500 μM H 2 O 2 , Ce6@Co + TA, and Ce6@Co + TA + 500 μM H 2 O 2 . TA acts as a ⋅OH fluorescence probe, forming fluorescent 2-hydroxy terephthalic acid (TAOH) upon reaction with ·OH, which emits at 425 nm.

Article Snippet: Ce6 was procured from Frontier Scientific, Inc. (Logan, UT, USA).

Techniques: Irradiation, Fluorescence

Journal: International Journal of Pharmaceutics: X

Article Title: Synergistic photodynamic and chemodynamic therapy using hypoxia-adaptive Ce6@Co nanoparticles for enhanced tumor suppression

doi: 10.1016/j.ijpx.2025.100348

Figure Lengend Snippet: Intracellular uptake, intracellular H 2 O 2 levels under normoxia and hypoxia, and dark toxicity. (a) Confocal images and quantitative analysis of free Ce6 and Ce6@Co nanoparticle intracellular uptake in SCC7 cells. Scale bar: 30 μm, *** p < 0.005. (b) Confocal images and quantitative analysis of intracellular H 2 O 2 levels of SCC7 cells under normoxia and hypoxia. Scale bar: 30 μm. ***p < 0.005. (c) Cell viabilities of SCC7 cells treated with free Ce6 or Ce6@Co nanoparticles at various concentrations (0, 2.5, 5, 10, 15, and 20 μM of Ce6) under dark conditions. * p < 0.05. N.S. = No significance.

Article Snippet: Ce6 was procured from Frontier Scientific, Inc. (Logan, UT, USA).

Techniques:

Journal: International Journal of Pharmaceutics: X

Article Title: Synergistic photodynamic and chemodynamic therapy using hypoxia-adaptive Ce6@Co nanoparticles for enhanced tumor suppression

doi: 10.1016/j.ijpx.2025.100348

Figure Lengend Snippet: In vitro therapeutic effects and ROS amplification of Ce6@Co nanoparticles on SCC7 cells. (a and b) Cell viabilities of SCC7 cells treated with free Ce6 (5 μM) or Ce6@Co nanoparticles (equivalent 5 μM of Ce6) under (a) normoxic and (b) hypoxic conditions with or without 670 nm laser irradiation (50 mW/cm 2 ) for 30 s. *p < 0.05, ***p < 0.005. N.S. = No significance. (c) CLSM images and quantitative analysis comparing intracellular ROS generation in SCC7 cells under the following conditions: Ce6@Co nanoparticles with irradiation under normoxia, Ce6@Co nanoparticles without irradiation under hypoxia, or Ce6@Co nanoparticles with irradiation under hypoxia. Scale bar: 30 μm. ***p < 0.005.

Article Snippet: Ce6 was procured from Frontier Scientific, Inc. (Logan, UT, USA).

Techniques: In Vitro, Amplification, Irradiation

Journal: International Journal of Pharmaceutics: X

Article Title: Synergistic photodynamic and chemodynamic therapy using hypoxia-adaptive Ce6@Co nanoparticles for enhanced tumor suppression

doi: 10.1016/j.ijpx.2025.100348

Figure Lengend Snippet: In vitro apoptosis assay. (a) CLSM images for Annexin V (green) and PI (red)-stained SCC7 cells treated with free Ce6 (5 μM) or Ce6@Co nanoparticles (equivalent 5 μM of Ce6) under normoxic and hypoxic conditions with or without 670 nm laser irradiation (50 mW/cm 2 ) for 30 s. Scale bar: 30 μm. Quantitative analysis of (b) Annexin V and (c) PI fluorescence intensities in each group. ***p < 0.005. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)

Article Snippet: Ce6 was procured from Frontier Scientific, Inc. (Logan, UT, USA).

Techniques: In Vitro, Apoptosis Assay, Staining, Irradiation, Fluorescence

Journal: International Journal of Pharmaceutics: X

Article Title: Synergistic photodynamic and chemodynamic therapy using hypoxia-adaptive Ce6@Co nanoparticles for enhanced tumor suppression

doi: 10.1016/j.ijpx.2025.100348

Figure Lengend Snippet: In vivo therapeutic effects of Ce6@Co nanoparticles on SCC7-tumor-bearing mice. (a) Tumor volumes of SCC7-tumor-bearing mice after PBS (control), free Ce6 (1 mg/kg) + laser irradiation, Ce6@Co nanoparticles (an equivalent Ce6 dose of 1 mg/kg), or Ce6@Co nanoparticles (an equivalent Ce6 dose of 1 mg/kg) + laser irradiation treatments. Free Ce6 and Ce6@Co nanoparticles were administered via intratumoral injection. In the two groups designated for PDT, tumors were irradiated with a 670 nm laser at 100 mW/cm 2 for 20 min, 6 h post-injection. ** p < 0.01, ***p < 0.005. (b) Tumor weight and (c) photographs of excised tumors from each treatment group at the end of the experiment. Scale bar: 1 cm. *p < 0.05, **p < 0.01, ***p < 0.005. (d) Representative images of tumor tissue H&E and TUNEL staining. Nuclei are stained blue (DAPI), and apoptotic cells are stained green (TUNEL). Scale bars: 200 μm. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)

Article Snippet: Ce6 was procured from Frontier Scientific, Inc. (Logan, UT, USA).

Techniques: In Vivo, Control, Irradiation, Injection, TUNEL Assay, Staining

Journal: International Journal of Pharmaceutics: X

Article Title: Synergistic photodynamic and chemodynamic therapy using hypoxia-adaptive Ce6@Co nanoparticles for enhanced tumor suppression

doi: 10.1016/j.ijpx.2025.100348

Figure Lengend Snippet: In vivo biosafety study. (a) Body weight changes of SCC7 tumor-bearing mice in each group after PBS (control), free Ce6 (1 mg/kg) + laser irradiation, Ce6@Co nanoparticles (an equivalent Ce6 dose of 1 mg/kg), or Ce6@Co nanoparticles (an equivalent Ce6 dose of 1 mg/kg) + laser irradiation treatments. (b and c) Serum biochemistry analysis of mice after treatment. (b) BUN and CREA for renal function, and (c) ALT, AST, and ALP for hepatic function. (d) H&E staining of major organs (liver, lung, spleen, kidney, and heart) from each treatment group, indicating no observable organ damage. Scale bars: 100 μm.

Article Snippet: Ce6 was procured from Frontier Scientific, Inc. (Logan, UT, USA).

Techniques: In Vivo, Control, Irradiation, Staining