Enhancement of zinc (II) phthalocyanine photophysical properties in water by sulfonatocalix[4]arene‐based micelles

Abstract

Zinc phthalocyanines have demonstrated a wide range of applications as photosensitisers, particularly in organic synthesis, photocatalysis and photodynamic therapy. Although the introduction of ionic groups on the macrocycle periphery increases their water solubility, aggregation phenomena remain as a significant drawback for their application. In this study, amphiphilic sulfonatocalix[4]arene-based micelles were used to promote the monomerization of a cationic phthalocyanine through host–guest interactions. A comprehensive spectroscopic characterization was conducted, varying the concentration of sulfonatocalix[4]arene, and binding parameters were calculated to determine the optimal conditions for complete monomerization of the photosensitizer in water. Under these conditions, the combination of sulfonatocalix[4]arene and the photosensitizer activated its photophysical activity in aqueous media, showing significant singlet oxygen photoproduction, photocatalytic capability and photostability.