The eradication of excess ROS is pivotal for wound healing acceleration, as evidenced by numerous studies [
26]. Despite CGA’s potent antibacterial, antioxidant, and anti-inflammatory properties, its bioactivity often lacks stability [
27]. The microsphere structures of SrC-MPNs, however, are designed to preserve CGA’s bioactivity, thus enhancing wound healing potential. Through the employment of 2′,7′-dichlorodihydrofluorescein diacetate (DCFH-DA) as a ROS probe, the levels of ROS in the culture media were assessed by measuring the intensity of green fluorescence, as depicted in
Fig. 3A. Pronounced green fluorescence was observed when Raw264.7 was exposed to a medium containing 3 mmol/L H
2O
2. However, when Raw264.7 was cultured with various SrC-MPNs concentrations or extracts of MN-PP and SrC-MPNs@MN-PP (with 100 µg/mL SrC-MPNs). A higher concentration of SrC-MPNs results in a reduction of ROS fluorescence intensity when subjected to the same 3 mmol/L H
2O
2 stimulus. Particularly, culturing in SrC-MPNs@MN-PP (with 100 µg/mL SrC-MPNs) medium demonstrated a marked reduction in ROS fluorescence (
Fig. 3B). To quantify the amount of ROS, Raw264.7 cells were stained with the kit and collected for analysis by flow cytometry (
Fig. 3C), and the flow cytometry data were quantified (
Fig. 3D). Collectively, these findings underscore SrC-MPNs@MN-PP’s capability to efficaciously mitigate excess ROS. To further validate the antioxidant potential of SrC-MPNs, fibroblasts were co-cultured with SrC-MPNs and subsequently exposed to 3 mmol/L H
2O
2. An evident positive correlation between SrC-MPNs concentration and fibroblast activity was discerned, corroborated by
Fig. 3E. In the end, after verifying the advantage of SrC-MPNs@MN-PP in reducing ROS, the functionality of SrC-MPNs@MN-PP in inducing phenotypic changes in macrophages was further investigated. Raw264.7 cells were co-cultured with extracts from different treatments for 24 h, using an untreated extract as the control. Through reverse transcription quantitative real-time PCR (RT-qPCR), the mRNA expression of the M2 macrophage marker, Arg-1, was gauged. Notably, SrC-MPNs@MN-PP extract treatment significantly augmented Arg-1 expression levels, suggesting an enhanced M2 repolarization post-treatment (
Fig. 3H). The specific primer sequences employed for RT-qPCR are detailed in Fig. S4 (Supporting information). Collectively, these findings reinforce the notion that SrC-MPNs@MN-PP not only mitigates excess ROS but also catalyzes the shift of M0 macrophages towards the pro-healing M2 phenotype, effectively modulating the inflammatory milieu in diabetic wounds.