Fig. 2: Influence of the nature of cyclodextrin on the Na₂S₅/cyclodextrin host-guest interaction.

a Experimental Job’s plot obtained following H₃ shift for α-cyclodextrins, β-cyclodextrins, and γ-cyclodextrins in presence of Na₂S₅ (respectively, top-down). Second order polynomial fitting whose maximum is obtained for the stoichiometric ratio, ∑, (see “Methods” section) matches with the stoichiometry of the complex. b ¹H NMR titration plots for the inclusion of Na₂S₅ in the different cyclodextrins cavities and fitted binding isotherms determined from H₃ signal for α-cyclodextrins, β-cyclodextrins, γ-cyclodextrin with indication of the resulting association constants K_α5, K_β5, and K_γ5 for the corresponding 1:1 inclusion complex. The statistic error relative to the chemical shift measurement was obtained by the calculation of the standard deviation of 10 similar and independent points and is estimated to 9%. The plotted error bars were calculated considering the uncertainties propagation (see “Methods” section).