Interactions of D-cellobiose with selected chloride salts: A ¹³C NMR and FT-IR study

The interactions of cellulose model compound d-cellobiose with chloride salts of Zn(2+), Ca(2+), Li(+), Sn(2+), La(3+), Mg(2+), K(+) and NH4(+) were evaluated by measuring the (13)C NMR chemical shift changes (Δδ) of the disaccharide due to the addition of salts in D2O. The KCl and NH4Cl showed similar Δδ changes due to interactions only with the Cl(-) anion. Whereas other chloride salts showed interactions with both cation and anion. Among these salts the total interactions are in the order: Zn(2+)>Sn(2+)>Li(+)>Ca(2+)~La(3+)>Mg(2+). The FT-IR spectra of D-cellobiose-chloride salt 1:2 mixtures also indicate that KCl and NH4Cl interacts similarly with D-cellobiose in the solid state.