ABSTRACT
The interaction of a cationic water-soluble porphyrin, 5,10,15,20-tetrakis [4-(3-pyridiniumpropoxy)phenyl]porphyrin tetrakisbromide (TPPOC3Py), with anionic surfactant, sodium dodecyl sulfate (SDS), in aqueous solution has been studied by means of UV-vis, (1)H NMR, fluorescence, circular dichroism (CD) spectra and dynamic laser light scattering (DLLS), and it reveals that TPPOC3Py forms porphyrin-surfactant complexes (aggregates), including ordered structures J- and H-aggregates, induced by association with surfactant monomers below the SDS critical micelle concentration (cmc), and forms micellized monomer upon the cmc, respectively. The position of TPPOC3Py in the micelle is determined, which is not in the micelle core instead of intercalated among the SDS chains, most likely with the pyridinium group extending into the polar headgroup region of the micelle.
Subject(s)
Porphyrins/chemistry , Surface-Active Agents/chemistry , Water/chemistry , Circular Dichroism , Light , Magnetic Resonance Spectroscopy , Protons , Scattering, Radiation , Sodium Dodecyl Sulfate/chemistry , Solubility , Solutions , Spectrometry, Fluorescence , Spectrophotometry, UltravioletABSTRACT
The interaction of a cationic water-soluble porphyrin, 5,10,15,20-tetrakis[4-(3-pyridiniumpropoxy)phenyl]prophyrin tetrakisbromide (TPPOC3Py), with beta-CD and HP-beta-CD in aqueous solution has been studied by UV-vis, 1H NMR, 2D-NOESY and MALDI-TOF MS, and it reveals that a stable 1:1 inclusion complex between TPPOC3Py and HP-beta-CD or beta-CD has formed, in which one of the meso substituents of porphyrin ring has deeply penetrated through the cavity of HP-beta-CD from secondary face. The inclusion constants of the complexes of TPPOC3Py-beta-CD and TPPOC3Py-HP-beta-CD are (1.6+/-0.2)x10(3) M-1 and (8.9+/-0.4)x10(4) M-1, respectively.
