Fig. 2.

Characterization of ROS Nano@Feb-1. (a) Mechanism of drug release from ROS Nano@Feb-1. ROS Nano@Feb-1 consumes ROS and releases Feb-1 by responding to excess ROS after injury. (b) ROS Nano@Feb-1 morphology under scanning electron microscopy. ROS Nano@Feb-1 is a uniform spherical particle with a size of about 105 nm, scale bar = 200 nm. (c) NTA analysis of ROS Nano@Feb-1 particle size distribution. NTA analysis indicates that ROS Nano@Feb-1 particle size is concentrated at 107 nm. (d–e) DLS and Zeta Potential analysis of ROS Nano@Feb-1 (n = 3). (f–g) Drug release rates of ROS Nano@Feb-1 in different solutions (n = 3, one-way ANOVA, Tukey's post hoc tests, ****P < 0.0001). (h–i) Transmission electron microscopy images analysis of ROS nano after 1 h of H₂O₂ oxidation (n = 3, one-way ANOVA, Tukey's post hoc tests, ****P < 0.0001). The particle size increased after the H₂O₂ oxidation treatment, scale bar = 200 nm. (j) Zeta potential analysis of ROS Nano@Feb-1 after incubation with different concentrations of H₂O₂ solution for 1 h (n = 4, one-way ANOVA, Tukey's post hoc tests, **P < 0.01, and ***P < 0.001). (k–l) Tz-A6 peptide could promote the docking of ROS Nano@DID nanoparticles to Huc-MSCs, scale bar = 200 μm. (n = 20, one-way ANOVA, Tukey's post hoc tests, ****P < 0.0001).