The development of efficient photosensitizers is vital for advancing photodynamic therapy (PDT), a non-invasive cancer treatment. Although zinc phthalocyanine (ZnPc) has garnered significant attention as a photosensitizer in preclinical studies, its clinical application is hindered by poor solubility and a tendency to aggregate, despite its high absorption coefficient and low dark toxicity. To address these challenges, we developed a novel ZnPc-conjugated periodic mesoporous organosilica (PMO) nanoparticle, which enhances the photosensitizer's solubility, photostability, and biodegradability. The PMO nanoparticles retained the characteristic mesoporous structure, exhibited strong fluorescence emission, and effectively generated singlet oxygen. In vitro studies using 4T1 cells, along with in vivo experiments on a tumor-bearing mouse model, demonstrated that under 675nm laser irradiation, the ZnPc-PMO nanophotosensitizer induced reactive oxygen species, leading to significant inhibition of tumor growth. This ZnPc-bridged PMO nanophotosensitizer holds great promise for enhancing PDT efficacy and biocompatibility, offering a potential platform for multimodal phototherapeutic strategies.
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