pH-controlled self-assembling of meso-tetrakis(4-sulfonatophenyl)porphyrin-chitosan complexes.
Solid meso-tetrakis(4-sulfonatophenyl)porphyrin (TPPS(4))-chitosan supramolecular complexes were prepared by addition of porphyrin to an aqueous solution of chitosan at pH values. The precipitates obtained were assigned as 1 (pH 6.8) and 2 (pH 2.5) and characterized by spectroscopic, thermal, and microscopic methods. Spectroscopic investigation confirmed the presence of TPPS(4) and chitosan in both products and that the porphyrin is highly self-associated. H-type (stacked) of TPPS(4) aggregation was proposed for 1 and J-type (tilted) for 2. Thermal analysis revealed different pyrolysis routes of the complexes depending on their structural diversity. Light microscopic analysis indicated fibrous and lamellar microstructures, respectively, for 1 and 2. SEM and AFM analysis showed that both complexes consist of compact nanostructures; their size and interconnection is different for 1 and 2. Based on structural inferences, self-assembling hierarchy models were proposed for both of the TPPS(4)-chitosan supramolecular complexes.
Synytsya
Alla
A
Department of Analytical Chemistry, Institute of Chemical Technology, Prague 16628, Czech Republic. sinical@vscht.cz
Synytsya
Andriy
A
Blafková
Petra
P
Ederová
Jana
J
Spevacek
Jiri
J
Slepicka
Petr
P
Král
Vladimír
V
Volka
Karel
K
D048271:Chitosan / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D018625:Microscopy, Atomic Force; D015394:Molecular Structure; D049329:Nanostructures / Q000737:chemistry; D010316:Particle Size; D011166:Porphyrins / Q000737:chemistry*; D019265:Spectroscopy, Near-Infrared; D013499:Surface Properties; D013696:Temperature
D011166:Porphyrins; C092400:meso-tetrakis(4-sulfonatophenyl)porphyrin; D048271:Chitosan