Characteristics of the complexing of chitosan with sodium dodecyl sulfate, according to IR spectroscopy data and quantum-chemical calculations

Resumo

The complexing of protonated chitosan with dodecyl sulfate ions in water solutions is studied using IR spectroscopy data and quantum-chemical calculations. It is established that the electrostatic interaction between the protonated amino groups of chitosan and dodecyl sulfate ions is apparent in the IR spectrum as a band at 833 cm⁻¹. The need to consider the effect the solvent has on the formation of hydrogen-bound ion pairs [CTS⁺ ⋅ C₁₂H₂₅O₃^-] is shown via a quantum-chemical simulation of the equilibrium geometry and the energy characteristics of complexing and hydration.