Ciaftalan zinc

The determination of the Stern-Volmer constant (KSV) for photosensitizers, a key parameter for characterizing energy transfer efficiency to oxygen, enables the understanding and optimization of photosensitizer functionality.In this study, a strategy was proposed for determining the KSV by replacing the anal. of the oxygen-dependent behavior of fluorescence intensity with a direct correlation between singlet oxygen quantum yield (ΦΔ) and mol. oxygen.Zinc phthalocyanine (ZnPc) was selected for this work due to its promising photosensitizing properties.Through theor. anal. using the rate equation model and exptl. absorption measurements, the KSV of ZnPc was found to be 2.4(2) μM^-1.To verify the accuracy of the KSV, an oxygen-varying correlated fluorescence methodol. was applied, reinforcing the reliability of the results.In addition, the determination of the KSV is achievable even in the absence of specific ΦΔ values and without the use of a standard reference

Photothermal therapy/photodynamic therapy (PTT/PDT), as a noninvasive therapeutic modality, has been extensively applied in superficial tumor treatment. However, their curative effects were largely weakened due to hypoxia and an elevated glutathione (GSH) microenvironment. Herein, zinc phthalocyanine (ZnPc) and sulfasalazine (SAS) coloaded nanoaggregates (Z-S@B NAs) with Prussian blue (PB) functionalization (PB/Z-S@B NAs) were fabricated via self-assembly and using an in situ oxidative polymerization method for tumor PTT/PDT sensitization. The designed PB/Z-S@B NAs were capable of triggering local hyperthermia and generating substantial reactive oxygen species (ROS) under 660- and 808-nm laser irradiation. Notably, the PB/Z-S@B NAs exhibited favorable catalase-like (CAT-like) activity that decomposed hydrogen peroxide into oxygen, which further enhanced tumor cell sensitivity to PTT/PDT. Moreover, SAS from the PB/Z-S@B NAs remarkably decreased the antioxidant GSH level, resulting in a synergetic tumor-killing effect. Collectively, this study provides a versatile nanoplatform to overcome intrinsic antitumor effect and enhance tumor sensitivity to PTT/PDT.