Complexation of Lignin Dimers with β-Cyclodextrin and Binding Stability Analysis by ESI-MS, Isothermal Titration Calorimetry, and Molecular Dynamics Simulations

• DOI: 10.1021/acs.jpcb.1c09190
• Publication Date: 2022-02-17T17:14:37Z
• Authors: Kimberly R. Dean; Brian Novak; Mahsa Moradipour; Xinjie Tong; Dorel Moldovan; Barbara L. Knutson; Stephen E. Rankin; Bert C. Lynn
• Keywords: Isothermal Titration Calorimetry; Lignocellulosic Biomass

Lignin derived from lignocellulosic biomass is the largest source of renewable bioaromatics present on earth and requires environmentally sustainable separation strategies to selectively obtain high-value degradation products. Applications supramolecular interactions have potential isolate lignin compounds fractions by formation variable inclusion complexes with cyclodextrins (CDs). CDs are commonly used as selective adsorbents for many applications can capture guest molecules in their internal hydrophobic cavity. The strength between model that represent products be characterized assessing thermodynamics binding stability. Consequently, β-CD G-(β-O-4′)-G, G-(β-O-4′)-truncG (guaiacylglycerol-β-guaiacyl ether), G-(β–β′)-G (pinoresinol) were investigated empirically electrospray ionization mass spectrometry isothermal titration calorimetry, complemented molecular dynamics (MD) simulations. Empirical results indicate there substantial differences stability dependent linkage type. β–β′ dimer showed more bound states including 1:1, 2:1, 1:2 (guest:host) complexation and, based determinations, was consistently most energetically favorable guest. supported MD simulations reveal promising a 66% probability being compared 88% (unbiased distance trajectory explicit counting states). These outcomes material assist separations oligomers heterogeneous mixtures development isolations fractions.