Photophysical studies of meso-tetrakis(4-nitrophenyl) and meso-tetrakis(4-sulfophenyl) gallium porphyrins loaded into Pluronic F127 polymeric micelles

摘要

5,10,15,20-Tetra(4-nitrophenyl) porphyrinato gallium chloride (CIGaTNPP) and 5,10,15,20-tetra(4-sulfophenyl) porphyrinato gallium chloride (CIGaTSPP) and their metal free derivatives were successfully synthesised and were added to Pluronic F127 polymeric micelles to form CIGaTNPP-F127 (or H(2)TNPPF127) and CIGaTSPP-F127 (or H2TSPP-F127), respectively. The fluorescence and singlet oxygen generating behaviour of the porphyrins were investigated following incorporation. The fluorescence lifetimes were short-lived upon incorporation into the polymer, compared to the porphyrin alone; suggesting the quenching of the lifetimes of the porphyrin by the polymers. Singlet oxygen quantum yields were determined to be 0.55 and 0.59 for CIGaTSPP and CIGaTSPP-F127, respectively. Thus there is an increase in singlet oxygen quantum yields in the presence of Pluronic F127 compared to the porphyrin alone. CIGaTSPP-F127 (or H2TSPP-F127) showed higher values of the binding constant (Kb) as well as high values of the Stern-Volmer constant (K-sv) compared to CIGaTNPP-F127 (or H2TNPP-F127). (C) 2017 Elsevier B.V. All rights reserved.