Transformation of H-aggregates and J-dimers of water-soluble Tetrakis (4-carboxyphenyl) porphyrin in polyion complex micelles

Abstract

Tetrakis (4-carboxyphenyl) porphyrin (TCPP) and polyelectrolyte poly(N-methyl-2- vinylpyridinium iodide)-b-poly(ethylene oxide) (PMVP41-b-PEO205) can self-aggregate into polyion complex (PIC) micelles in alkaline aqueous solution. UV-vis spectroscopy, fluorescence spectroscopy, transmission electron microscope, and dynamic light scattering were carried out to study PIC micelles. Density functional theory (DFT) calculation method was applied to study the interaction of TCPP and PMVP41-b-PEO205. We found that the H-aggregates and J-dimers of anionic TCPP transformed in PIC micelles. H-aggregates of TCPP formed at the charge ratio of TCPP/PMVP41-b-PEO205 1:2 and J-dimer species at the charge ratio above 1:4, respectively. It is worth noting that the transformation from H-aggregates to J-dimer species of TCPP occurred just by adjusting the ratio of polymer and TCPP rather than by changing other factors such as pH, temperature, and ions.