Hemoglobin

Mannitol (200 mM, Catalog Number: M8140, Solarbio, China), sodium pyruvate (10 mM, Catalog Number: SP0100, Solarbio, China), uric acid (100 μM, Catalog Number: IU0150, Solarbio, China), tiron (20 mM, Catalog Number: T104954, Aladdin, China), hemoglobin (20 μM, Catalog Number: H8020, Solarbio, China), and monopotassium phosphate (1 mM, Catalog Number: P7392, Solarbio, China) were used to quench hydroxyl radical (OH·), hydrogen peroxide (H₂O₂), ozone (O₃), superoxide anion (O₂^·-), nitric oxide (NO·), and electron (e^-), respectively.
After treating cells with CAP for 2 or 4 min followed by incubation for 1 h, the quencher of each CAP component was added, separately. Viruses were added to cells and incubated for 1 h. The medium was refreshed, and cells were cocultured with viruses for additional 46 h prior to subsequent analyses.

Ammonium tetrachloropalladate (II) ((NH₄)₂PdCl₄, 98%) and dl-methionine (C₅H₁₁NO₂S, 99.9%) were obtained from Adamas-Beta (Shanghai, China). Ascorbic acid (C₆H₈O₆, 99.9%), human serum albumin (HSA), ribonuclease A (RNA), cytochrome C, transferrin, bovine serum albumin (BSA), lysozyme, and hemoglobin were obtained from Solarbio (Beijing, China). All competitive metal ions and glucose used for selectivity testing were acquired from Sinopharm Chemical Reagent Co. Ltd. (Shanghai, China). All reagents were used as received without further purification. Ultrapure water (resistivity: 18.2 MΩ⋅cm) was obtained from a Millipore purification system.