Reactive oxygen species (ROS) scavenging ability of Fe-dihydromyricetin (DMY) nano-coordinated polymer particles (NCPs). (A) Schematic representation of the ROS scavenging process by Fe-DMY NCPs. (B−E) Ultraviolet-visible (UV-vis) spectroscopy absorbance spectra of methylene blue (MB) (B), 2,2′-azinobis (3-ethylbenzothiazoline-6-sulfonic acid ammonium salt) (ABTS) (C), 2,2-diphenyl-1-picrylhydrazyl (containing 10%–20% benzene) (DPPH) (D), and 2-phenyl-4,4,5,5-tetramethylimidazoline-3-oxide-1-oxyl (PTIO) (E) treated with Fe-DMY NCPs at different concentrations. (F) ROS scavenging ratio (%) of Fe-DMY NCPs based on the characteristic peak of MB UV-vis absorption spectrum (664 nm). (G) ABTS radical scavenging ratio (%) of Fe-DMY NCPs based on the characteristic peak of ABTS UV-vis absorption spectrum (734 nm). (H) DPPH radical scavenging ratio (%) of Fe-DMY NCPs based on the characteristic peak of DPPH UV-vis absorption spectrum (519 nm). (I) PTIO radical scavenging ratio (%) of Fe-DMY NCPs based on the characteristic peak of PTIO UV-vis absorption spectrum (557 nm). The inset shows photographs of the ROS scavenging experimental subgroups. Data are presented as the mean ± standard error of mean.