Defect engineering synergistically boosts the catalytic activity of Fe-MoO_v for highly efficient breast mesh antitumor therapy.

Abstract

The demand for breast mesh with antitumor properties is critical in post-mastectomy breast reconstruction to prevent local tumor recurrence. Molybdenum-based oxide (MoO_x) exhibits enzyme-like activities by catalyzing endogenous hydrogen peroxide to produce reactive oxygen species for inducing tumor cell apoptosis. However, its catalytic activity is limited by insufficient active sites. Herein, a defect engineering strategy is proposed to create redox nanozymes with multiple enzymatic activities by incorporating Fe into MoO_x (Fe-MoO_v). Fe-MoO_v is subsequently integrated into polycaprolactone (PCL) to fabricate breast meshes for establishing an enzyme-catalyzed antitumor platform. The doping of Fe into MoO_x formed numerous defect sites, including oxygen vacancies (OV) and Fe substitution sites, synergistically boosting the binding capacity and catalytic activity of Fe-MoO_v. Density functional theory calculations demonstrated that the outstanding peroxidase-like catalytic activity of Fe-MoO_v resulted from the synergy between OV and Fe sites. Additionally, OV contributes to the localized surface plasmon resonance effect, enhancing the photothermal capability of the PCL/Fe-MoO_v mesh. Upon near-infrared laser exposure, the catalytic activity of the PCL/Fe-MoO_v mesh is further improved, leading to increased generation of reactive oxygen species and enhanced antitumor efficacy, achieving 86.7% tumor cell mortality, a 264% enhancement compared to the PCL/MoO_x mesh.