Polyethylene glycol peg

Poly (ethylene glycol) (PEG, Alfa Aesar), ε-caprolactone (ε-CL) (Alfa Aesar, Reston, VA), stannous octoate (Sn(Oct)₂), RPMI-1640 and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) were purchased from Sigma (St. Louis, MO), GEF was purchased from Meilun Co., Ltd (Dalian, China). Dimethylsulfoxide (DMSO), anhydrous ethanol, methanol (HPLC grade) and isopropyl alcohol were purchased from KeLong Co., Ltd (Chengdu, China). IL-6 ELISA Kit and TGF-β1 ELISA Kit were purchased from ChengLin Biological Technology (Beijing, China). Hydroxyproline assay kit was purchased from Nanjing Institute of Biological Engineering (Nanjing, China). Ki-67, EGFR and CD31 polyclonal antibody were purchased from Bioworld Technology (Nanjing, China).

Synthesis of NiO_x NPs was performed by adopting the chemical precipitation method from our previous studies^{51 (link)}. 99.999% nickel(II) nitrate hexahydrate (Ni(NO₃)₂ ∙ 6H₂O) was purchased from Sigma-Aldrich, polyethylene glycol (PEG) and sodium hydroxide (NaOH) were purchased from Alfa Aesar and Merck. All solutions were prepared by dissolving them into deionized water (DI) and the entire reaction process was performed at room temperature. Ni(NO₃)₂6H₂O was dispersed in DI water to obtain a dark green solution, and PEG was added during continuous magnetic stirring. Then, NaOH was slowly added dropwise at a rate of about 10 µl per drop. This process was carried out under vigorous stirring until the pH of the solution was adjusted to 10. After the completion of the reaction, the colloidal precipitate was washed with DI water several times to remove residual impurities and chemicals. The colloidal precipitate was then baked at 80 °C for overnight and calcined in a furnace at 285 °C for 2 h to obtain black powder. The produced black powder was pulverized into finer particles through a grinder.

Commercial-grade chitosan powder was obtained from Shandong Chitin Powder Factory (Shandong, China). It has a viscosity-average molecular weight of 600,000 g/mol and a deacetylation degree of 95%. The graphene oxide (GO) powder form was bought from Jiangsu XFNANO Materials Tech Co., Ltd (China). Polyethylene glycol (PEG, molecular weight of 2000 g/mol) was purchased from Alfa Aesar (USA). Methyl orange (MO, molecular weight of 327.33 g/mol) was obtained from CARLO ERBA Reagents s.r.l. Milan, Italy. The remaining reagents were of analytical quality and did not need further purification before use.

Analytical grade reagents gold chloride trihydrate (HAuCl₄·3H₂O), N-hydroxysuccinimide (C₄H₅NO₃), sodium tetrahydroborate (NaBH₄), polyethylene glycol (PEG), bleomycin (BLM) and cysteamine (~95%) were obtained from (Alfa Aesar, China), (1-ethyl-3-(3-dimethylaminopropyl)-carbodimide hydrochloride) (EDC) and ethanol were purchased from (Aladdin Reagent, China). Doxorubicin was purchased from the Iranian Red Crescent Society. All stock solutions were prepared in purified water (Milli-Q Plus 185 Water Purifier, USA) having a resistivity close to 18 MΩ.cm. Experiments were conducted at room temperature. All reagents were used as provided, unless otherwise stated.

N-Methyl-2-pyrrolidone (NMP), potassium chloride (KCl), sodium chloride (NaCl), calcium chloride (CaCl), sodium hydroxide (NaOH) salts, fuming sulfuric acid, bovine serum albumin (BSA), and ACS-grade hydrochloric acid (HCl) were obtained from VWR international (Solon, OH, USA). Polysulfone (PSf) and cellulose acetate at molecular weights (mw) of 40,000 and 100,000 g/mol were obtained from Sigma Aldrich (St. Louis, MI, USA). Polyether ether ketone (PEEK) was obtained from Polysciences Inc. (Warrington, PA, USA). Polyethylene glycol (PEG) at molecular weights of 200, 600, 1000, 4000, 8000, 10,000, and 20,000 g/mol was obtained from Alfa Aesar (Ward Hill, MA, USA).