Mesoporous polydopamine loaded with silver nanoparticles and quercetin for bacterial keratitis treatment through antibacterial and anti-angiogenic mechanisms.

Bacterial keratitis (BK) is a serious blinding eye disease, with pathological features mainly including corneal stromal opacity, edema, inflammatory response, and corneal neovascularization (CoNV). Timely intervention and treatment are required in clinical practice. In this study, we successfully prepared mesoporous polydopamine (MPDA) using a soft-template method, and further introduced silver nanoparticles (Ag NPs) and quercetin (Que) onto its surface, resulting in the effective preparation of a Q/AMP nanocomposite with dual functions of anti-angiogenesis and antibacterial activity, which is expected to be applied in the prevention and treatment of BK. The experimental results demonstrated that Q/AMP, based on favorable in vitro and in vivo biocompatibility, effectively inhibited the proliferation, migration, and tube formation of human umbilical vein endothelial cells (HUVECs), as well as markedly inhibited CoNV in rats. In the in vitro antibacterial experiment, Q/AMP exhibited broad-spectrum and highly efficient antibacterial activity. In the BK animal model, Q/AMP achieved a 97.0% antibacterial rate, higher than Levofloxacin (LVFX) eye drops (77.4%), and Q/AMP showed a greater therapeutic effect, reducing corneal opacity score from 2.5 with LVFX to 0.8 and effectively alleviating ocular symptoms. Therefore, this study presents a promising new strategy for the treatment of infectious keratitis. Q/AMP has demonstrated strong capabilities in antibacterial, anti-angiogenic, and anti-inflammatory aspects, which may attract more attention to the deeper integration of biomaterials and infectious keratitis research.