Absolute alcohol

CaO (analytical reagent, AR), H₃PO₄ (AR), H₂O₂ (AR), NaOH (AR), and absolute alcohol (AR) were all purchased from Beijing Chemical Works (Beijing, China); type-I purity collagen was purchased from Collagen Biotechnology Co. Ltd. (Hebei, China); KBr (spectroscopically pure) was purchased from Botianshengda Co. Ltd. (Tianjin, China); phosphate buffer solution (PBS), Dulbecco's Modified Eagle Medium (DMEM), and fetal bovine serum (FBS) were all purchased form Thermo Fisher Scientific (USA); MTT and DMSO were purchased from Sigma (USA); Trizol reagent was purchased from Invitrogen (USA); SYBR Green I and the PrimeScript™ RT reagent Kit was purchased from TaKaRa (Japan); and FITC phalloidin was purchased from Alexis (USA).

All the chemical reagents were directly used without further purification. N, N-dimethyl formamide (DMF), dichloromethane (DCM), PLA, potassium iodide (KI), 1,3- diphenylisobenzofuran (DPBF), and menadione were purchased from Sigma-Aldrich. Absolute alcohol, glutaraldehyde and osmium tetroxide were purchased from Beijing Chemical Reagent Company. An ROS assay kit, JC-1, and one step TUNEL apoptosis assay kit were obtained from the Beyotime Institute of Biotechnology, China. Hypocrellin A (HA, 98%), 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide (XTT) and 3-(N-morpholine) propanesulfonic acid (MOPS) were purchased from Shanghai Yuanye Bio-Technology Co., Ltd.