*2.1. Materials*

Chrysin, 2,2 -azobisisobutyronitrile (AIBN) and acrylamide (AM) were purchased from Shanghai Aladdin Biochemical Technology Co., Ltd. (Shanghai, China). Methyl alcohol and acetic acid were purchased from Chengdu Cologne Chemicals Co., Ltd. (Chengdu, China). Methacrylic acid (MAA) was purchased from Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China). Ethylene glycol dimethacrylate (EGDMA) was purchased from Alfa Aesar (Qingdao, China). Chloramphenicol and oxytetracycline were purchased from Shanghai Maclin Biochemical Technology Co., Ltd. (Chengdu, China).
