Effects of ligand density on hydrophobic charge induction chromatography: molecular dynamics simulation.

摘要: High ligand density is usually required in hydrophobic charge induction chromatography (HCIC) for high adsorption capacity. However, it not clear to what extent the alters and desorption behaviors, or if this leads protein conformational transition within adsorbent pores. In present study, molecular dynamics simulation performed examine effects of HCIC using a 46-bead beta-barrel coarse-grained model pore established our earlier work. Four densities (1.474, 1.769, 2.212, 2.949 micromol/m(2)) are simulated at 298.15 K. The simulations indicate that both capacity irreversibility increase with density. found fastest occurs 2.212 micromol/m(2) rather than highest studied. Analyses trajectories, protein-ligand interaction energy, free energy map there repulsion when unfavorable contacts ligands occur. There an enhanced micromol/m(2), which increases barrier region reduces opportunities get stable adsorption, thus leading decreased rate. At however, mild coverage provides abundant causes maximum unfolding. following simulations, complete irreversible observed all densities, agreement easy pH-induced elution behavior experimentally. It suitable balance between attraction electrostatic slowest kinetics Moreover, analysis unfolded distribution indicates unfolding mainly on surface desorption. behaviors have been comprehensively elucidated by thermodynamic analyses.