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Intracellular bacterial (ICB) infection is one of the most life‐threatening cases of drug resistance, and photodynamic therapy (PDT) is challenged by limited light penetration into tissues and unspecific toxicity to host cells. Herein, theranostic nanoparticles (NPs) are developed to facilitate on‐demand activation of photosensitizers inside ICBs and persistent PDT of deep‐tissue ICB infections. Mechanoluminescent SrAl2O4:Eu2+ and persistence luminescent CaS:Eu2+ are sequentially deposited on mesoporous silica to prepare mSC, followed by encapsulation by bacterial membranes with loaded nitroreductase (NTR)‐activatable methylene blue (nMB) to obtain mSC‐nMB@BM NPs. The fluorescence quenching of nMB with mSC offers few cytotoxicities even under ultrasonication, and bacterial membrane coatings mediate the specific NP internalization into ICB‐infected macrophages. Bacterial pore‐forming toxins trigger nMB release from NPs, and intrabacterial NTR rejuvenates methylene blue probes from nMB for real‐time imaging of ICB infections. Ultrasonication of NPs continuously excites the rejuvenated methylene blue to generate reactive oxidative species and reduce viable ICBs by 3.54 log magnitude folds. NP treatment on ICB‐infected mice exhibits full survival and restores viscera functions without any pathological abnormality. Therefore, this concise NP design demonstrates capabilities of bacterial membrane‐mediated specific internalization, bacterial toxin‐triggered release and intrabacterial NTR‐rejuvenation of fluorescent probes, and persistent internal light‐illumination for ICB theranostics. [ABSTRACT FROM AUTHOR]

Thrombus therapy is challenged by potential bleeding risk of thrombolytic agents, and external irradiation is usually needed in thrombus imaging. Herein, highly efficient theranostic platforms are designed for piezoelectric‐Fenton‐photodynamic thrombolysis and endogenous thrombus imaging in response to the elevated shear stress at the thrombus site. Piezoelectric tetragonal barium titanate (tBT) nanoparticles (NPs) are coated with Fe3+‐coordinated metal‐organic frameworks (MOFs), followed by inoculation of chlorin e6‐luminol conjugates and heparin absorption to obtain theranostic tBT@MOFCL/Hep NPs. Shear stress‐induced piezopotential on NPs accelerates Fe3+/Fe2+ transformation to deplete MOF layers, activates Fenton reaction and produces reactive oxidative species (ROS) for non‐pharmacological thrombolysis. In the meantime, the site‐specific ROS generation oxidizes luminol and the chemiluminescent resonance energy transfer with chlorin e6 generates red fluorescence for thrombus imaging without using external light irradiation. After intravenous injection into a carotid artery thrombosis model, the heparin‐mediated thrombus targeting yields 6.5‐fold higher luminescent intensity at the thrombus site. Thrombi in the carotid arteries are almost completely dissolved with integration of piezoelectric dynamic therapy, piezopotential‐enhanced Fenton reaction, and chemiluminescence‐excited photodynamic therapy, while causing no haematologic and histopathologic abnormality. This study demonstrates a concise strategy to generate shear stress‐responsive built‐in piezoelectric potentials, site‐specific non‐pharmacological thrombolysis, self‐illuminating, and stenosis degree‐adaptable thrombus imaging. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) has evolved as an essential method for infection control, but is confronted with challenges in terms of low oxygen supply, possible toxicity during light irradiation, and nonpersistent action. Herein, to address these limitations, black phosphorus (BP) is used as a photosensitizer and decorated with Pt nanoparticles and aminobenzyl-2-pyridone (APy) moieties to obtain BP@APy-Pt. The stability of BP is improved through the capture and occupation of lone-pair electrons after reductive deposition of Pt nanoparticles and covalent conjugation of APy. Pt nanoparticles on BP@APy-Pt catalyze the decomposition of endogenous H 2 O 2 to produce oxygen for consecutive cycles with a stable production capacity. The light exposure to BP@APy-Pt generates significantly higher 1 O 2 levels than those of BP/light, and the generated 1 O 2 is partially captured by APy moieties. The captured 1 O 2 during 20 min of illumination shows a constant release for 24 h in the dark. The cycled storage and release feature eliminates the toxicity of 1 O 2 at high levels during illumination and leads to efficient destruction of S. aureus and P. aeruginosa. Compared to the healing rates after treatment with BP/light (57.6%), BP@Pt/light (64.8%), BP@APy/light (77.8%), and BP@APy-Pt (48.5%), the skin wounds with infected S. aureus are fully healed after BP@APy-Pt/light treatment. Blood vessels and hair follicles are regenerated to resemble those of normal skin. Thus, this study expands the PDT strategy through integration with oxygen generation, 1 O 2 storage, and persistent release to promote bactericidal efficacy and eliminate side effects.