24.0 mL of 0.01MH2O2, 24.0 mL of A549 cell sample solution,
24.0 mL of 55 mM ABTS, and 10.0 mL of Fe3O4 MNPs stock
solution were added into 185.0 mL of 0.2 M acetic acid-acetate
buffer solution (pH 4.0) and then the solution was mixed up to
make it uniform