Inverse Opal Photonic Hydrogels for Blue‐Edge Slow Photon‐Enhanced Photodynamic Antibacterial Therapy

Abstract

Photodynamic therapy is promising for combating bacteria by reactive oxygen species. However, the therapeutic efficiency of photodynamic antibacterial therapy (PDAT) is largely hindered by limited photon absorption and the low quantum yield of photosensitizers. Herein, a novel light‐harvesting platform is designed by decorating photosensitizer chlorine e6 (Ce6) into an inverse opal photonic hydrogel (Ce6/IOPG) framework for efficient light utilization to enhance PDAT. It is shown that the generating efficiency of singlet oxygen (1O2) can be tuned by the relative positions of the photonic bandgap (PBG) of IOPG and the absorption band of Ce6. The coupling of the slow photon effect with the efficient dispersion of Ce6 allows for a maximum generation of 1O2 of approximately 69.5‐fold and markedly enhances PDAT activity upon low light irradiation when the blue edge of PBG overlaps with the absorption band of Ce6. Particularly, slow photons at the blue edge show advantages in improving 1O2 generation compared to those at the red edge. The variation in 1O2 generation by altering the incident angle of light provides direct evidence for the slow photon effect in Ce6/IOPG. This work provides insights into blue‐edge slow photons in photodynamic enhancement and offers an advisable design principle for efficient antibacterial therapy.

Construction of Inverse–Opal ZnIn2S4 with Well–Defined 3D Porous Structure for Enhancing Photocatalytic H2 Production

“…Then, a periodic ordered structure makes it produce a photonic bandgap and can slow the photon propagation in photonic crystals (i.e., a slow light effect), which can be absorbed effectively by photonic crystals, thus producing more photo-induced carriers [15]. Therefore, the 3DOM photocatalyst also exhibits a superior carriers' separation and mass transfer, except for a unique light absorption capacity [16][17][18][19][20][21][22][23][24]. It is foreseeable that the 3DOM semiconductor is a promising kind of photocatalyst.…”

Spatiotemporally Controllable Bifunctional Micellar-Carbon Dot Supernanoparticles for Wounds Healing

“…The indiscriminate use of antibiotics contributes to a relentless surge in bacterial resistance, potentially pushing humanity into a scenario where “no drugs are available”, thereby intensifying the challenges of treating infected wounds. − Antibacterial photodynamic therapy (aPDT) has garnered increasing attention as a light-controllable, rapid, efficient, noninvasive, and broad-spectrum antimicrobial strategy for addressing infected wounds. ,− In the aPDT process, photosensitizers activated by specific wavelengths swiftly produce a multitude of reactive oxygen species (ROS), − capable of directly impairing bacterial cell walls, membranes, lipids, and nucleic acids, thereby accomplishing antimicrobial effects. ,− This antibiotic-free therapy notably mitigates the likelihood of antibiotic-resistant bacteria. ,, However, despite the potent bactericidal efficacy demonstrated by aPDT through the induction of ROS generation, its side effect of localized ROS overdose, resulting in increased inflammation and tissue damage, has not been adequately addressed. , …”

Self-Healing Dynamic Hydrogel Microparticles with Structural Color for Wound Management

“…To enhance the multifunctionality of wound dressings, innovative structural designs have been incorporated into hydrogel systems [ 14 – 17 ]. A representative example is inverse opal hydrogel patches, whose periodic porous architecture gives rise to structural colors [ 18 – 20 ]. Inverse opal-based patches can not only carry various therapeutic agents, such as antimicrobial peptides (AMPs) and vascular endothelial growth factor (VEGF), but also utilize their structural color features for reporting the drug release progress [ 21 – 23 ].…”