Dibutyltin oxide

Trans-Ferulic acid (≥99%) (FA), dibutyltin oxide (DBTO), and K₂CO₃ were supplied by Sigma Aldrich (Milan, Italy), H₂ was supplied by Siad, palladium on carbon (10% on carbon, 55% water), and ethylene carbonate were supplied by TCI (Frankfurt, Germany). Poly(butylene succinate adipate), PBSA (BioPBSTM FD92PM), was supplied by PTT MCC Biochem Company (Banchang Town, Thailand) and was previously dehumidified at 50 °C for 5 h before its use. Luperox^®101XL45 was used in this work as a crosslinking peroxide and was supplied by Arkema (Dusseldorf, Germany). This reagent was used for the crosslinking reaction between the PBSA and the oligomer PHEF produced in this work. Irganox^® 1010, as a commercial antioxidant additive, was acquired from BASF (Pontecchio Marconi, Italy).

Vanillin (VL) (99%), ethylene carbonate (EC) (98%), potassium carbonate (K₂CO₃, 99%), sodium sulphate (Na₂SO₄), dibutyltin oxide (DBTO) (>98%), 2‐aminoethanol (>99%), trimethylolpropane tris [poly (propylene glycol), amine terminated] ether (Jefm) (average Mn of 440 g mol⁻¹), trimethylolpropane triglycidyl ether (TMPTGE), 1,2‐dimethylimidazole, and dibutyltin dilaurate (DBTDL) (>95%) were purchased from Sigma‐Aldrich. N,N‐dimethylformamide (DMF, ACS, Reag. Ph. Eur.), ethyl acetate (EtOAc, ACS, Reag. Ph. Eur.), and ethanol (EtOH) were purchased from VWR Chemicals. All chemicals and reagents were used as received.

Poly(ethylene glycol) (PEG, M_n = 2,000), poly(propylene glycol) (PPG, M_n = 2,050), dibutyltin dilaurate (DBT) (95%), 1,6-hexamethylene diisocyanate (HDI) (98%), ω-pentadecalactone (98%), ethylene glycol (99.8%), dibutyltin oxide (DBTO) (98%), 1,6-diphenyl-1,3,5-hexatriene (DPH), Pluronic^® F127 (PEG₁₀₀PPG₇₀PEG₁₀₀ triblock polymer), phosphate buffered saline (PBS), docetaxel (DTX), and doxorubicin (DOX) were purchased from Sigma-Aldrich (Singapore). Organic solvents including anhydrous toluene, diethyl ether, isopropanol (IPA), tetrahydrofuran (THF) and ethanol were of ACS grade and obtained from commercial sources. Dulbecco's modified Eagle's medium (DMEM), penicillin, streptomycin sulfate and fetal bovine serum (FBS) were purchased from Life Technology Co., Ltd. (Waltham, MA, USA). Thiazolyl blue tetrazolium bromide (MTT), hematoxylin and eosin staining kit were purchased from Yeasen Biotechnology Co., Ltd. (Shanghai, China). Dialysis tubing (MWCO 3,500 Da) was purchased from Spectrum Laboratories (USA). PEG, PPG, ω-pentadecalactone and ethylene glycol were dried under vacuum overnight before use. PBS buffer (0.01 M, pH = 7.4) were prepared by dissolving PBS powder in deionized water. Other materials were used as received.