A study of the photophysicochemical and antimicrobial properties of two zinc phthalocyanine-silver nanoparticle conjugates

摘要

This work reports conjugation of two mono carboxy substituted zinc phthalocyanines with glutathione capped silver nanopartides (GSH-AgNPs). The photophysicochemical behaviour of the novel phthalocyanines-silver nanoparticle conjugates was investigated together with simple mixtures of the silver nanopartides with low symmetry phthalocyanines (i,e. with no direct chemical bond formation). It was observed that upon conjugation of the phthalocyanines to the silver nanopartides, a blue shifting of the Q band was induced. The triplet lifetimes and quantum yields improved upon conjugation as compared to the phthalocyanines alone. Fluorescence lifetimes and quantum yields decreased for conjugates compared to the phthalocyanines alone due to quenching caused by the silver nanopartides. The low symmetry phthalocyanines and their conjugates showed antimicrobial activity against Escherichia coli in the presence and absence of light.