A gold–chitosan composite with low symmetry zinc phthalocyanine for enhanced singlet oxygen generation and improved photodynamic therapy activity. (24th May 2018)

• Record Type: Journal Article
• Authors: Dube, Edith; Oluwole, David O.; Prinsloo, Earl; Nyokong, Tebello
• Is Part Of: New journal of chemistry. Volume 42:Number 12(2018)
• Page Start: 10214
• Page End: 10225
• Publication Date: 2018-05-24
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/c8nj00801a
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : A gold–chitosan composite with low symmetry zinc phthalocyanine showed no dark cytotoxicity activity and improved photodynamic therapy compared to that of the phthalocyanine alone. Abstract : Novel zinc(ii ) 3-(4-((3, 17, 23-tris(4-(benzo[ d ]thiazol-2-yl)phenoxy)phthalocyanine-9-yl)oxy)phenyl)propanoic acid (complex3 ) was synthesised. Complex3 was subsequently reacted with gold nanoparticles (AuNPs), chitosan (CT) and a gold–chitosan (AuCT) hybrid to form3 -AuNPs, 3 -CT and3 -AuCT, respectively. The conjugates afforded a decrease in fluorescence quantum yield with a corresponding increase in the triplet and singlet quantum yields compared to complex3 . The in vitro dark cytotoxicity and photodynamic therapy activity (PDT) of complex3 and3 -AuCT composites were investigated against epithelial breast cancer cells (MCF-7) with both the samples showing minimum dark cytotoxicity. They both accounted for a cell viability of ≥90% at a concentration of ≤59.2 μg mL −1 .3 -AuCT showed better PDT activity (compared to3 alone) with less than 50% viable cells at a concentration of ≥29.6 μg mL −1 making it potentially applicable for PDT. On the other hand, AuCT displayed some activity against cancer cells, probably due to photothermal activity since gold is a light absorber, however it had more than 50% viable cells at a concentration of ≤59.2 μg mL −1 .