A gallium-porphyrin metal–organic framework that functions as an all-in-one theranostic platform by simultaneously delivering high-flux singlet oxygen and controlled Ga3+ release is reported, establishing a single-material theranostic paradigm that conjoins mechanistic diagnostics with potent antibacterial therapy.
Photodynamic therapy (PDT) efficacy is severely compromised by tumor hypoxia and the scarcity of efficient type-I photosensitizers, necessitating multimodal therapeutic strategies. Herein, we report a porphyrin-Cu (II) covalent organic framework (TBCOF) with intrinsic bifunctional photodynamic and chemodynamic activities. Sequential DOX encapsulation and hyaluronic acid (HA) surface functionalization afford HA-TBCOF@DOX, a tumor-targeted nanoplatform integrating four synergistic therapeutic modalities. Under 660 nm laser irradiation, the nanoplatform generates ROS signatures consistent with both type-I and type-II pathways for PDT, while the intrinsic Cu2+ centers are proposed to catalyze a Fenton-like reaction consistent with •OH generation for CDT. Concurrently, observations of O2 evolution suggest catalase-like activity that may decompose endogenous H2O2 into O2, alleviating hypoxia and potentiating oxygen-dependent PDT. Efficient photothermal conversion and pH-triggered DOX release contribute to photothermal and chemotherapeutic effects, respectively, while HA-mediated CD44 targeting enhances cellular uptake and therapeutic specificity. In vitro and in vivo studies demonstrate that laser-activated HA-TBCOF@DOX effectively suppresses tumor growth, induces apoptosis, and exhibits no apparent systemic toxicity under the tested experimental conditions. This work establishes a multifunctional COF-based nanoplatform that addresses PDT limitations observed in this study by integrating intrinsic PDT and CDT, providing a robust strategy for synergistic multimodal cancer therapy.
Yongjie Mo, Jie Hou, Hong-Li Li et al.· Materials Today Bio· 0 citations
The worldwide escalation of antimicrobial resistance poses an urgent threat to global health, prompting the pursuit of alternative treatments. In this study, we report the synthesis and characterization of an innovative photosensitizer nanoconjugate comprising monosubstituted 3‐[4‐(sodium sulfonate)phenoxy] zinc phthalocyanine (ZnSTPc) and nitrogen‐doped graphene quantum dots (NGQDs) for antimicrobial photodynamic therapy (aPDT). Electron paramagnetic resonance measurements showed that NGQDs‐ZnSTPc generated significantly higher levels of singlet oxygen and hydroxyl radicals than either component alone. This enhancement was associated with FRET, with a calculated efficiency of 37.19%. In vitro photodynamic antibacterial assays demonstrated that NGQDs‐ZnSTPc reduced
Escherichia coli
survival to 0.09% at 200 µg/mL, while no viable
Staphylococcus aureus
were detected at 50 µg/mL within the of assay under 680 nm light irradiation (200 mW/cm
2
, 20 min). These results underscore the potential of NGQDs‐ZnSTPc as an effective antimicrobial photosensitizer, offering advantages of lower irradiation intensity and shorter treatment time compared with existing systems.
Metal-free photoactive nanomaterials offer a promising strategy to address antimicrobial resistance, yet strategies enabling tuneable and efficient activity remain limited. Here, we introduce a materials-led approach to antibacterial photodynamic therapy by engineering carbon dots (CDs) with a strained dibenzocyclooctyne (DBCO) surface motif. Direct installation of the strained alkyne yields photoresponsive DBCO-CDs that exhibit potent, selective light-activated antibacterial activity. Under low-energy LED irradiation (395–405 nm), DBCO-CDs achieve >99.9% inactivation of Gram-positive bacteria, including Staphylococcus aureus, while remaining inactive in the dark and against Gram-negative bacteria. Mechanistic studies reveal that the intact strained alkyne is essential for activity, with non-strained-featuring analogues showing no efficacy. Reactive oxygen species (ROS)-trapping experiments implicate H2O2-mediated oxidative stress, while sub-cellular fluctuation imaging demonstrates rapid collapse of intracellular dynamics, consistent with metabolic failure. Notably, DBCO-CDs disrupt established biofilms, reducing biomass by 57% upon irradiation. Collectively, our findings establish strained-alkyne surface engineering as a powerful and modular strategy for imparting photodynamic functionality to carbon nanomaterials, advancing next-generation antimicrobial and antibiofilm technologies.
Cristina Santi, A. Eley, Yuiko Takebayashi et al.· Nanoscale· 0 citations
Managing pneumonia caused by multidrug-resistant (MDR) bacteria presents significant clinical challenges. The near-infrared II (NIR-II) laser irradiance exhibits strong photothermal conversion capabilities, making it a promising candidate for photothermal and chemodynamic therapies as non-antibiotic strategies. However, traditional methods are often hindered by issues such as the uncontrollable production of reactive oxygen species and the low efficiency associated with NIR-II photothermal therapy. This underscores the necessity for precisely regulated and highly effective synergistic therapies. To address these limitations, we have innovatively developed a defect/interface dual-engineered nanozyme (PtPb@SbO3-x) and comprehensively characterized its atomic-scale structure and catalytic mechanisms using density functional theory calculations and synchrotron radiation techniques. In vitro experiments demonstrated that PtPb@SbO3-x could efficiently eliminate drug-resistant bacteria and disrupt biofilm structures under low-concentration hydrogen peroxide and NIR-II irradiation while exhibiting excellent biocompatibility. In pneumonia models, the nanozyme enabled rapid infection clearance and significantly reduced inflammatory responses via synergistic photothermal and chemodynamic therapy effects. Furthermore, integrated multi-omics analyses-including metabolomics, transcriptomics, and proteomics-systematically uncovered the molecular mechanisms driving its therapeutic efficacy. This study successfully establishes a non-antibiotic nanozyme-based therapeutic strategy that is efficient, low in toxicity, and non-invasive for treating MDR bacterial infections. It also provides a solid theoretical basis and technical framework for the rational design of defect/interface dual-engineered nanoplatforms.
Z. Qiu, Danyan Wang, Zijun Jin et al.· Materials Today Bio· 0 citations
PCNZnCy adapts to the wound's specific microenvironment, enabling it to kill bacteria, reduce oxidative stress, and promote tissue regeneration, and makes it a strong candidate for multifactorial, complex wound pathologies, in which multiple complications overlap.
Yipeng Pang, F. M. Amona, Hanyuan Liu et al.· Theranostics· 0 citations
For visual anticounterfeiting and drug sensing, a novel rubidium-based organic framework material (named Rb-CMNDI) has been synthesized. Using N, N'-bis(carboxymethyl)-1,4,5,8-naphthalenedicarboximide (H2CMNDI) as the organic linker, a thermally stable metal-organic framework (MOF) with photothermal stimulus response properties was successfully constructed. Upon UV irradiation, Rb-CMNDI darkens, then turns red upon heating. Combined DFT calculations and experimental studies reveal that UV irradiation generates NDI* radical, subsequent thermal activation drives their assembly into π-stacked dimers, narrowing the bandgap from 2.72 to 1.27 eV and resulting in the emergence of a red phase and this finding uncovers a photothermal cooperative radical to dimer transformation mechanism. This unique color evolution behavior was further applied to the collaborative construction of anticounterfeiting labels with transition metal MOF, achieving visual and multilevel anticounterfeiting functions. Additionally, this MOF can also be used as a highly sensitive fluorescent sensor for the detection of the urinary tract infection nitrofurantoin, with a limit of detection (LOD) of 0.36 μM while maintaining good specificity. This work provides a novel strategy for designing alkali-metal MOFs with photothermal responsive properties, promising for intelligent encryption and antibiotic residue monitoring.
Chao Zhang, Zixiao Liu, Zhe Gong et al.· Inorganic Chemistry· 0 citations
