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Published on: August 20, 2012
Complex formation between rhodamine B and poly(sodium 4-styrenesulfonate) studied by 1H-NMR
Ignacio Moreno-Villoslada1, Rodrigo Gonzalez, Susan Hess
1Instituto de Química, Facultad de Ciencias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile. imorenovilloslada@uach.cl
Abstract:
A 1H NMR study is presented for the binding of rhodamine B (RB) to the polyanion containing aromatic groups poly(sodium 4-styrenesulfonate) (PSS), which is also evidenced by diafiltration. 1H NMR spectra showed an accentuated upfield shift of proton H6' of the benzoic ring of RB at pH 7, indicating the stacking of RB onto PSS. The corresponding structure is proposed which is in accordance to Hunter and Sanders rules. At pH 2, an upfield shift of the xanthene protons of RB would indicate a highly condensed state for this molecule.
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