*3.3. Continuous Variation Method*

The continuous variation method reported by Job [34] provides an estimate of the preferred stoichiometry in solution based on the measured changes in a physical parameter (in the present case, the chemical shift of sample protons). A series of solutions were prepared using as solvent a 1:1 mixture of deuterated water and deuterated methanol. In each solution, the ratio of host and guest, *r*, varied in steps of 0.1 while their sum (γ-CD]<sup>0</sup> + [EFV]0) was kept constant, at a value of 0.01 M. For the host, γ-CD, *r* is thus defined as:

$$
\tau\_{\gamma \text{-CD}} = [\gamma \text{-CD}]\_0 / \langle [\gamma \text{-CD}]\_0 + [\text{EFV}]\_0 \rangle \tag{1}
$$
