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Continuous variation data: 1:1 or 2:2 weak complexes?

Ana Sayago·Maravillas Boccio·Agustin G Asuero
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Abstract

An attempt to distinguish between 1:1 and 2: 2 weak complexes from continuous variation data is given. A modification of the Heller and Schwarzenbach's method which involves the use of the absorbance ratio y=A/A(lim) (once the limiting absorbance, A(lim) is known) may be applied to 1:1 weak complexes. This allows checking if the slope obtained is close to the theoretical value of -0.25. A curvature appears and the residuals have a pattern when a wrong 1:1 model is selected for a true 2:2 stoichiometry.

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Ana Sayago, Maravillas Boccio, Agustin G Asuero. 2005-05-13. Continuous variation data: 1:1 or 2:2 weak complexes?. https://doi.org/10.1016/j.ijpharm.2005.01.038

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