Interleaving-twisted nanoarchitectured porous organic polymer synergizes photoactivity enhancement and nanozyme-powered microenvironment remodeling for advanced infected wound therapy
While systemic antibiotics remain the frontline defense against bacterial infections, the global antimicrobial resistance crisis urgently demands non-inducible therapeutic alternatives. Despite the inherent ability of phototherapy to bypass resistance, its efficacy in state-of-the-art porphyrin-based photosensitizers (PSs) is critically limited by aggregation-caused quenching (ACQ) of photoactivity. To overcome this dual challenge, we designed a conformation-adaptive porous organic polymer (DFP-POP). Featuring a spatially interleaving-twisting molecular architecture achieved by linking triazine-porphyrin units (H<sub>2</sub>TDPP, featuring eight amino groups) <i>via</i> Schiff-base polymerization with acetyl-rich bridging ferrocene (possessing a sandwich-staggered structure), DFP-POP synergizes three antimicrobial modalities to realize a cascade mechanism. This unique 3D twisted conformation inherently suppresses ACQ by preventing π-π stacking. It simultaneously facilitates broad-spectrum light absorption through extended conjugation and enables multimodal bioactivity <i>via</i> ferrocene-mediated enzyme-mimetic catalysis. DFP-POP orchestrates a self-enhanced multimodal therapy by manipulating oxygen in the infected microenvironment (IME). Its catalase-like (CAT-like) activity converts endogenous H<sub>2</sub>O<sub>2</sub> to O<sub>2</sub>, alleviating hypoxia to enable self-sustaining photodynamic therapy (PDT). Additionally, its pH-responsive peroxidase-like (POD-like) activity precisely generates bactericidal ˙OH specifically within the weakly acidic IME. Consequently, DFP-POP operates through a synergistic cascade characterized by photothermal membrane disruption, hypoxia-alleviated <sup>1</sup>O<sub>2</sub> production, and enzyme-amplified ˙OH generation. In murine wound models, DFP-POP treatment achieved near-complete epithelialization by day 9, significantly outperforming controls. This work pioneers the integration of molecular conformation engineering with microenvironment-responsive catalytic cascades in porous organic polymer design, establishing a new paradigm for combating drug-resistant infections. The synergy between physical phototherapy and biochemical catalysis provides a blueprint for developing advanced smart therapeutic materials.
Authors
- Minggang Du (ORCID: https://orcid.org/0000-0002-4155-8591)
- Feng Gao (ORCID: https://orcid.org/0000-0003-3173-1650)
- Zhifu Zhang (ORCID: https://orcid.org/0000-0002-9709-7851)
- Peng Sun (ORCID: https://orcid.org/0009-0008-0218-6343)
- Fei Gao (ORCID: https://orcid.org/0000-0003-2496-3701)
- Yanli Qin (ORCID: https://orcid.org/0000-0001-7003-0430)
Institutions
- Weifang Medical University (CN)
- Second Hospital of Shandong University (CN)
- Weifang Chinese Medicine Hospital (CN)
- Weifang University (CN)
Publication Details
- Journal
- RSC Advances
- Published
- 2025-01-01
- DOI
- https://doi.org/10.1039/d5ra07169k
- Primary Topic
- Nanoplatforms for cancer theranostics
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Natural Science Foundation of Shandong Province