Iron 2 chloride tetrahydrate

Iron(II) chloride tetrahydrate (FeCl₂·4H₂O), cobalt chloride hexahydrate (CoCl₂·6H₂O), manganese chloride tetrahydrate (MnCl₂·4H₂O), nickel chloride hexahydrate (NiCl₂·6H₂O), Sodium tungstate dihydrate (Na₂WO₄·2H₂O), hexadecyl trimethyl ammonium Bromide (CTAB), 1,3-diphenylisobenzofuran (DPBF) and 3,3,5,5-Tetramethylbenzidine (TMB) were purchased from Shanghai Macklin Biochemical Co., Ltd. (Shanghai, China). All chemicals were of analytical grade and used without further purification.
The ROS detection kit (S0033S) and propidium iodide (PI) (ST511) were purchased from Beyotime Biotechnology Co., Ltd. (Shanghai, China). The primary antibodies, Anti-GAPDH and anti-AID, were purchased from Abways Technology Co., Ltd. (Shanghai, China). and North American ImmunoWay Biotechnology Company (TX, USA). The ECL Substrate Kit (P0018FS) was obtained from Beyotime Biotechnology Co., Ltd. (Shanghai, China).
Human DLBCL SU-DHL-4 and OCI-LY19 cell lines were purchased from BeNa Culture Collection (BeNa, #BNCC340176, #BNCC338225) (Suzhou, China).

Enzymatic hydrolysis lignin (EHL) was acquired from Hong Kong Laihe Biotechnology Co., Ltd. (Hong Kong, China) The hydroxyl content, the number-average molecular mass, and polydispersity of EHL are 2.67 mmol/g, 1430 g/mol, and 1.22, respectively. Doxorubicin hydrochloride was purchased from Shanghai Macklin Biochemical Co., Ltd. (Shanghai, China) Purity is higher than 98%. Tetrahydrofuran (THF) of analytical-grade purity was provided by Beijing Chemical Reagent Company (Beijing, China). Folic acid was supplied by Chembase Co., Ltd. (Shanghai, China) Iron (II) chloride tetrahydrate and Iron (III) chloride and albumin from bovine serum were purchased from Shanghai Macklin Biochemical Co., Ltd. (Shanghai, China) Poly (dimethyl diallyl ammonium chloride) solution (PDAC, Mw < 100,000, 35 wt.% in water, 100–200 CP (25 °C)) was provided by Shanghai Aladdin Bio-Chem Technology Co., Ltd. (Shanghai, China).

Nickel (II) nitrate hexahydrate (Ni(NO₃)₂·6H₂O; 98%, CAS No. 7791-20-0, Alfa), iron (II) chloride tetrahydrate (FeCl₂·4H₂O; 99.95%, CAS No. 13478-10-9, Macklin), erbium(III) chloride (ErCl₃; 99.9%, CAS No. 10138-41-7, Aladdin), urea (CH₄N₂O; 99%, CAS No. 57-13-6, Aladdin), Nafion solution (5%, CAS No. 31175-20-9, Sigma-Aldrich), hydrochloric acid (HCl; 36%–38%, CAS No. 7647-01-0, Sinopharm Group Chemical Reagent Co., Ltd.), ruthenium (IV) oxide (RuO₂; 99.9%, CAS No. 12036-10-1, Aladdin), and potassium hydroxide (KOH; 90%, CAS No. 1310-58-3, Macklin) were used directly without further purification. The ultrapure water (≥18.25 MΩ cm) used in this work was obtained through the Ulupure UPR-III-10T (Sichuan Ulupure Ultrapure Technology Co., Ltd.) system. Toray carbon paper (CP; TGP-H-060, 5% wet proofing) was purchased from Fuel Cell Earth.