Photoproperties, PVP formulation and 19F NMR of a Zn phthalocyanine with 24 magnetically pseudo-equivalent fluorine atoms

Abstract

In an attempt to investigate its potential as a PDT [Formula: see text]F MRI molecular theranostic, a Zn phthalocyanine with 24 pseudo-equivalent fluorine atoms was designed and prepared. Compared to its H analogues, the fluorinated derivative has a much higher generation of singlet oxygen. [Formula: see text]F NMR signals in CDCl3 showed that all the fluorine atoms are magnetically pseudo-equivalent with only two close fluorine signals. Formulation in PVP (polyvinylpyrrolidone), a FDA-approved additive, enabled water-solubilization of the phthalocyanines but no satisfying [Formula: see text]F NMR signal could be obtained, probably due to self-quenching caused by aggregation.

Probing the Interactions of Porphyrins with Macromolecules Using NMR Spectroscopy Techniques

“…For this purpose, the synthesis of a Zn-phthalocyanine (ZnPc) was reported with 24 fluorine substituents that gave rise to two proximate intense 19 F NMR signals from the magnetically pseudo-equivalent fluorine atoms of the isomeric mixture. PVP formulation of this hydrophobic F-substituted ZnPc, however, lead to a collapse of the intense 19 F resonance into a low-intensity very broad signal, which indicated that the ZnPc exists as aggregates in the PVP environment [ 168 ].…”