Photodynamic therapy (PDT) faces significant challenges in treating solid tumors due to the hypoxic tumor microenvironment and high degree of tumor heterogeneity. To address this issue, this study employed a strategy of acceptor planarization coupled with tunable terminal aryl modulation to design and synthesize a series of type I photosensitizers (DPP‐1–DPP‐3) with systematically tuned push–pull character and electronic structures. Among them, DPP‐3 exhibits outstanding near‐infrared emission and hypoxia‐tolerant reactive oxygen species generation. Building on this core module, we integrated a biomarker‐responsive unit into DPP‐3 to construct an intelligent theranostic probe, DPP‐CE. This probe retains high photodynamic activity both before and after activation, ensuring reliable therapeutic efficacy independent of local activation efficiency, while its near‐infrared fluorescence signal is specifically activated only within the tumor microenvironment, enabling imaging‐guided precise treatment. Both in vitro and in vivo experiments demonstrate that DPP‐CE allows high‐contrast fluorescence imaging of tumors and effectively inhibits tumor growth under both normoxic and hypoxic conditions, while showing good biosafety. This work not only provides a new strategy for developing high‐performance type I photosensitizers, but also offers a modular approach that integrates a therapeutic core with a biomarker‐responsive unit, paving the way toward programmable theranostic platforms adaptable to tumor heterogeneity.
Xuemei Dong, Lingan Zeng, Yunlong Liu et al.· Advanced Healthcare Material...· 0 citations
The clinical efficacy of photodynamic therapy (PDT) is fundamentally limited by the scarcity of efficient photosensitizers (PSs) and the oxygen dependence of singlet-oxygen-mediated cytotoxicity. Here we report pentaperylene decaimide selenide (PPD-Se), a nanographene-derived photoelectronic material that functions as a high-performance Type-II photosensitizer. PPD-Se exhibits broadband absorption (300-650 nm), enhanced intersystem crossing enabled by a selenium-induced heavy-atom effect, a small ΔEST (0.50 eV), and a high 1O2 quantum yield (ΦΔ = 0.40). To address hypoxia-limited PDT, PPD-Se nanoparticles were covalently integrated with microalgae to construct an algae@PPD-Se biohybrid, in which PPD-Se is shielded from premature activation yet undergoes glutathione (GSH)-triggered release in the tumor microenvironment. Cleavage of disulfide linkages restores the photosynthetic activity of algae, enabling light-driven O2 production that alleviates local hypoxia and simultaneously boosts PPD-Se-mediated ROS generation. The biohybrid exhibits enhanced intracellular uptake, amplified ROS production, and potent apoptosis induction under white light-emitting diode (LED) irradiation (400-700 nm, 1 mW·cm-2). In vivo, algae@PPD-Se significantly downregulates HIF-1α, restores intra-tumoral oxygenation, and achieves marked tumor growth inhibition without observable systemic toxicity. This study introduces a dual-functional optoelectronic-biological PDT platform that couples a newly designed nanographene photosensitizer with photosynthetic oxygenation, offering a mechanistically driven strategy to overcome the oxygen dependency of PDT.
Gongcheng Ma, Nan Zhang, Hongrong Shi et al.· Advanced Healthcare Material...· 0 citations
In an era marked by increasing demand for advanced anticounterfeiting measures, we introduce a four-dimensional (4D) dynamic physical unclonable function that uses defect-engineered photoluminescence blinking in all-inorganic CsPbBr3 perovskite quantum dots (QDs) embedded within a polymethylmethacrylate matrix. Even within a single z-axis layer, this system achieves an unprecedented theoretical encoding capacity of more than 10216,742, while each device can generate up to 25 billion distinct codes. The QDs exhibit stochastic transitions between emissive and nonemissive states, enabling binary encoding across both spatial and temporal dimensions. The mechanism reveals that surface lead interstitials predominantly mediate nonradiative Auger recombination, whereas cesium vacancies act as effective Shockley-Read-Hall recombination centers, jointly governing the blinking of CsPbBr3. Alkali metal doping modulates this blinking behavior, providing precise control over the emission dynamics. Practical utility is demonstrated through a dual-mode authentication strategy that enables rapid field verification via standard smartphones while retaining high-security 4D verification via microscopy. We further establish a spatial-temporal dual-model authentication framework that integrates convolutional neural network (CNN)–based spatial matching with a temporal-branch dynamic check and decision-fusion assessment. The framework resists 14 adversarial attacks spanning replay, impersonation, temporal and local manipulation, Z-stack modification, projection forgery, and synthetic forgery attack, showing robust sequence-level security beyond frame-level CNN recognition. This work transforms what was once considered a detrimental phenomenon—QD blinking—into a valuable asset for dynamic, high-capacity encryption, opening new avenues for ultrasecure cryptographic systems.
