Abstract

Aromatic-aromatic interactions are found between the cationic molecule 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) and the molecule poly(sodium 4-styrenesulfonate) (PSS) which makes the overall interaction of TTC with PSS more intense than the interaction with other polyanions containing sulfonate groups and produces a decrease on the redox ability of ITC. Diafiltration was used to compare the binding of TTC to PSS, poly(sodium vinylsulfonate) (PVS), and the more hydrophobic poly(sodium 2-(N-acrylamido)-2-methylpropanesulfonate) (PAMPS). The UV-vis spectrum of TTC is changed in the presence of the aromatic polyanion. The 1H NMR signals of TTC are broadened and shifted in the presence of PSS, suggesting the occurrence of π-π interactions. Moreover, nuclear Overhauser effects (NOE) between the TTC and PSS protons are found. Possible structures for the complex are proposed. © 2007 American Chemical Society.