Cisplatin

Polyacrylamide (PAM) with a molecular weight of 5–6 megadaltons (MDa) was purchased from International Laboratory USA (South San Francisco, USA). Iron(iii) chloride hexahydrate (FeCl₃·6H₂O) was obtained from Acros (New Jersey, USA). Trisodium citrate dehydrate, urea, ethylenediamine, (3-mercaptopropyl)trimethoxysilane (MPS), urea, sodium diethyldithiocarbamate (DDTC, ≥99%) and matrix α-cyano-4-hydroxycinnamic acid (CHCA) were ordered from Sigma Aldrich (St. Louis, USA). Cisplatin (≥98%), glutathione (GSH), thioctic acid, carbonyldiimidazole, 1H-pyrazole-1-carboxamidine hydrochloride, tris(2-carboxyethyl)phosphine hydrochloride and triethanolamine were bought from Meryer (Shanghai, China).
For solvents, ethanol (EtOH), acetonitrile (MeCN), methanol (MeOH), and trifluoroacetic acid (TFA, 99%) were provided by VWR International Company (Radnor, Pennsylvania), while acetone (AC), dichloromethane (DCM), dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) were from RCI Labscan Ltd. (Bangkok, Thailand). All chemicals were of high performance liquid chromatography (HPLC) or analytical grade and utilized with no further purification, and distilled water (18.2 MΩ cm) was purified by using a Milli-Q ICW3000 system (Millipore, Billerica, MA) and degassed with nitrogen prior to usage.

Cisplatin was purchased from Meryer (Shanghai) Chemical Technology Co., Ltd. CS and sodium alginate were purchased from Shanghai Macklin Inc. CaCl₂ was purchased from Sun Chemical Technology (Shanghai) Co., Ltd. Gelatin was purchased from Shanghai Haohong Scientific Co., Ltd. Methacrylic anhydride, glacial acetic acid, and tetramethylenediamine were purchased from Meryer (Shanghai) Chemical Technology Co., Ltd. APS was purchased from Guangzhou Chemical Reagent Factory. Phosphate buffer and Duchenne Phosphate buffer were purchased from Beijing Solarbio Science & Technology Co., Ltd. PEGDA was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd. Rabbit anti-γH2AX antibody was purchased from Abcam Plc. 4′,6-Diamidino-2-phenylindole was bought from Sigma. Horseradish peroxidase-labeled goat anti-rabbit IgG antibody and Live & Dead Viability/Cytotoxicity Assay Kit was bought from Invitrogen Trading (Shanghai) Co., Ltd. Cell-CountingCCK-8 was bought from Dojindo Molecular Technologies (Japan). TUNEL apoptosis detection kit was bought from Promega (Beijing) Biotech Co., Ltd. Dulbecco's modified Eagle medium (DMEM), fetal bovine serum, and penicillin–streptomycin mix were purchased from Thermo Fisher Scientific Inc. All the other reagents and materials were used as received.