NIR-IIb fluorescence-image guided synergistic surgery/starvation/chemodynamic therapy: an innovative treatment paradigm for malignant non-small cell lung cancers

Background: Currently, the prognosis and survival rate for patients bearing non-small cell lung cancer (NSCLC) is still quite poor, mainly due to lack of efficient theranostic paradigms to exert in time diagnostics and therapeutics. Methods: Herein, for NSCLC treatment, we offer a customized theranostic paradigm, termed NIR-IIb fluorescence diagnosis and synergistic surgery/starvation/chemodynamic therapeutics, with a newly designed theranostic nanoplatform PEG/MnCuDCNPs@GOx. The nanoplatform is composed of brightly NIR-II emissive downconversion nanoparticles (DCNPs)-core and Mn/Cu-silica shell loaded with glucose oxidase (GOx) to achieve synergistic starvation and chemodynamic therapy (CDT). Results: It is found that 10% Ce3+ doped in the core and 100% Yb3+ doped in the middle shell greatly improves the NIR-IIb emission up to even 20.3 times as compared to the core-shell DCNPs without Ce3+ doping and middle shell. The bright NIR-IIb emission of the nanoplatform contributes to sensitive margin delineation of early-stage NSCLC (diameter < 1 mm) with a signal-to-background ratio (SBR) of 2.18, and further assists in visualizing drug distribution and guiding surgery/starvation/chemodynamic therapy. Notably, the starvation therapy mediated by GOx-driven oxidation reaction efficiently depletes intratumoral glucose, and supplies H2O2 to boost the CDT mediated by the Mn2+ and Cu2+, which consequently realized a highly effective synergistic treatment for NSCLC. Conclusion: This research demonstrates an efficient treatment paradigm for NSCLC with NIR-IIb fluorescence diganosis and image-guided synergistic surgery/starvation/chemodynamic therapeutics.

3. Synthesis of β-NaYF4:Yb/Er/Ce@NaYF4:Yb@NaYF4 1 mmol rare earth acetylized (RE: 30% Yb, 10% Ce, 2% Er, 58%Y) were added to a threenecked flask containing of 6.5 mL oleic acid (OA) and 15 mL 1-octadecene (ODE) and heated to 100 °C with stirring vigorously. Continuously heating to 125 °C under vacuum and keep 20-30 minutes until the rare earth acetylized is completely dissolved, a lightly yellow transparent solution was obtained. After the solution naturally cooled down to 48°C, 2.5 mmol NaOH (about 100 mg) and 4mmol NH4F (about 148.5 mg) were dissolved in methanol respectively, then quickly mixed and added into the three-necked flask, and vigorously stirred for 1 h until the solution turned from turbid white to clarified yellow. The mixture was then protected by the argon gas atmosphere and heated to 305 °C for 1h. The precipitated product was added with an equal amount of anhydrous ethanol and centrifuged at 5000rpm for 10min, then re-dispersed in 5 mL of cyclohexane.
Yb(CH3COO)3·6H2O (1 mmol) was dispersed in a mixture of 6.5 mL OA and 15 mL ODE, similar to the above, the solution was heated to 100 °C with stirring vigorously and then continuously raised the temperature to 125 °C under vacuum to completely dissolve.
Differently, after cooled down to 100 °C, the core (β-NaYF4:Yb/Er/Ce) were dropped into the solution. The following process was similar to the process of core (β-NaYF4: Er/Ce/Yb) mentioned above.
We used the same β-NaYF4:Er/Ce/Yb@NaYbF4 core-shell nanoparticle to synthesize β-NaYF4:Yb/Er/Ce@NaYbF4@NaYF4 core-shell-shell nanoparticles with different shell thicknesses. Firstly, the Y(CH3COO)3·6H2O (2.5 mmol), OA (10.0 mL), and ODE (15.0 mL) were put into a flask and heated at 140 °C under pumping with stirring for 1 hour to get rid of residual water and oxygen. Then the 0.10 M Y-OA precursor solution was received. The same core-shell nanoparticle batch was used to minimize any differences due to effects of the size, morphology, lanthanide doping, or any other variation of the core-shell that may occur between multiple synthesis. We followed the synthesis and sequential shelling procedure as

In Vitro Degradation Experiments
The PEG/MnCu@DCNPs@GOx suspension (1 mL, 5 mg mL -1 ) was placed in dialysis bags (MWCO = 3600), and then the dialysis bag was sealed to dialyze against another 39 mL of PBS at pH 7.5, 6.5, and 5.5, respectively, to simulate different biological environments.

Histological Examination
After 14 days of treatment, the heart, liver, spleen, lung, kidney, and tumors were excised and dehydrated with buffered formalin, ethanol, and xylene in turn. Finally, all types of dehydrated tissues were embedded in liquid paraffin to obtain stained slices for H&E staining by optical microscope.              Figure S15. H&E stained histological sections of the major organs (e.g., heart, liver, spleen, lung, and kidney). Scale bar: 100 μm.