Interactions of charged porphyrins with nonionic triblock copolymer hosts in aqueous solutions
The extent and locus of solubilization of guest and self-assembling surfactant host molecules in aqueous solutions are influenced by a variety of hydrophobic and hydrophilic interactions, as well as by more specific interactions between the various species present. By using a combination of two-dime...
| Publié dans: | Langmuir : the ACS journal of surfaces and colloids. - 1991. - 20(2004), 24 vom: 23. Nov., Seite 10399-412 |
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| Auteur principal: | |
| Autres auteurs: | , |
| Format: | Article |
| Langue: | English |
| Publié: |
2004
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| Accès à la collection: | Langmuir : the ACS journal of surfaces and colloids |
| Sujets: | Journal Article Research Support, U.S. Gov't, Non-P.H.S. Micelles PEO-PPO-PEO Polymers Porphyrins Propylene Glycols Solutions tetra(4-sulfonatophenyl)porphyrin Water plus... |
| Résumé: | The extent and locus of solubilization of guest and self-assembling surfactant host molecules in aqueous solutions are influenced by a variety of hydrophobic and hydrophilic interactions, as well as by more specific interactions between the various species present. By using a combination of two-dimensional heteronuclear 13C[1H] NMR correlation experiments with pulsed-gradient NMR diffusion and proton cross-relaxation measurements, the locations and distributions of porphyrin guest molecules have been established unambiguously with respect to the hydrophobic and hydrophilic moieties of a triblock copolymer species in solution. The interactions of tetra(4-sulfonatophenyl)porphyrin with the poly(propylene oxide) (PPO) and the poly(ethylene oxide) (PEO) segments of amphiphilic PEO-PPO-PEO triblock copolymer species have been measured as functions of solution conditions, including temperature and pH. The porphyrin/PEO-PPO-PEO interactions are established to be selective and adjustable according to the different temperature-dependent hydrophilicities or hydrophobicities of the PEO and PPO triblock copolymer components. Furthermore, such interactions influence the self-assembly properties of the block-copolymer amphiphiles in solution by stabilizing molecular porphyrin/PEO-PPO-PEO complexes well above the critical micellization temperature of the triblock copolymer species under otherwise identical conditions |
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| Description: | Date Completed 24.04.2006 Date Revised 01.12.2018 published: Print Citation Status MEDLINE |
| ISSN: | 0743-7463 |