Additional file 1 of Polyethylenimine-CO2 adduct templated CaCO3 nanoparticles as anticancer drug carrier
Creators: name: Luo, Wenli
name: Li, Zhaojian
name: Zhang, Ling
name: Xie, Xingyi
Publisher: name: figshare
Year: 2023
Subjects: subject: Biophysics
subject: Space Science
subject: Medicine
subject: Cell Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Pharmacology
subject: Biotechnology
subject: Chemical Sciences not elsewhere classified
subject: Cancer

description: Additional file 1: Figure S1. The reaction between PEI and CO2 in water. Without water, two amino groups in PEI react with one CO2 molecule forming alkylammonium carbamate zwitterions along the backbone. In the presence of water, some carbamate ions hydrolyze forming bicarbonate groups (shown in red). Water cannot improve CO2 content in the final product. Figure S2. FTIR and 1H NMR spectra of PEG-OTs and PEG-CHO. Figure S3. The XPS analysis of PEI-CO2@CaCO3-PEG-FA. (A) The survey scan showed the presence of C, N, O, and Ca elements. (B) High resolution of the C1S scan displayed a major C=N(C–O) peak at 286.5 eV (from FA) and a C–C peak at 284.5 eV (from PEI and PEG) and C=O peak at 288 eV (from FA). (C) High resolution of the N1S scan displayed a major C–N peak at 399 eV (from PEI and FA) and a minor C=N peak at 401 eV (from both FA and the Schiff base linkage between PEI backbone and PEG side chains). Figure S4. Particle morphology observation (A) and dynamic light scattering analyses (B) of the bare and DOX-loaded CaCO3 nanoparticles. No obvious morphological change before and after DOX loading. Particle size measured by DLS increased while zeta potentials decreased. The PEG grafting further decreased the zeta potential. Figure S5. The Ca2+ release before (A) and after (B) loading of DOX. The loaded drug did not affect the release behavior. Figure S6. The CO2 bubble formation from DOX/PEI@CaCO3-PEG-FA (top) and DOX/PEI -CO2@CaCO3-PEG-FA (bottom). Both are stable at pH 7.4 but decompose at pH 6.5. More bubbles can be observed in the bottom right image. Figure S7. Cell endocytosis of FITC-labeled CaCO3 nanoparticles. Green: CaCO3 particles; blue: nuclei. More particles were endocytosed by HeLa cells. Figure S8. The internalized particles were encapsulated into lysosomes of L929 cells and released Ca2+ ions there. Green: CaCO3 particles or Ca2+ ions; red: lysosomes; blue: nuclei. Figure S9. Histological observation of tumor sections after HE staining. The mice were treated with various nanoparticles for 14 d. A large area with very spare cell nuclei was found in the last two images, showing severe necrosis of tumor tissue in the two circumstances. Figure S10. Histological observation of various organ sections after HE staining. A tumor-like tissue was found in the liver from the saline group. Free DOX group demonstrated organic toxicity, showing small focal necrosis with infiltration of inflammatory cells in the heart, pyknosis and local necrosis in the liver, local necrosis in the spleen, thickened alveolar ducts in the lung, as well as glomeruli fusion with infiltration of inflammatory cells in the kidney. No pathological change was found in the organs from the other groups. Figure S11. FTIR spectra of PEI@CaCO3 particles obtained from a colloidal aqueous solution that had been kept for up to 240 d at room temperature. The characteristic absorption at 745 cm–1 indicates the υ4 CO32– band (in-plane bending) that is typical for vaterite. For calcite, the band is at 712 cm–1, which is absent in the spectra.