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Hydrophobic charge induction displacement chromatography (HCIDC) will override the mode of operation used in hydrophobic charge induction chromatography , separation and purification of the antibody has unparalleled advantages , but its process and mechanism is unknown , the impact of its industrial application . In this paper, the coarse-grained molecular dynamics analog the microscopic study HCIDC dynamic process , to examine its impact factors and parses its mechanism of action . Flat analog chromatography matrix by first uniformly distributed spherical particles of a regular hexagon , on which the coupling ligand 5 - amino- indole . Two parallel plate analog connection ligand chromatography bore lysozyme target solute selected the tributyl four decyl chloride , naphthalene ( TC ) , cetyl dimethyl benzyl ammonium chloride (CC) and benzyl cable chloride (BC) displacer , coarse-grained model were constructed in principle in accordance with the simplification of the Martini coarse-grained force field . On this basis , to chromatography orifices as the object of study, a detailed examination of the modes of interaction between lysozyme adsorption and replacement process , the ligand and the replacement agent , contact sites and energy of lysozyme conformational change process , lysozyme initial conformation and ligand density on the adsorption process , the type and concentration of the displacer displacement effect . The study results showed that the adsorption before , lysozyme constantly adjust its conformation and orientation in order to form the lowest energy ligand contact ; adsorption process , lysozyme in a natural state - partially unfolded state of dynamic change , and hydrophobic interactions with group , wherein residue Leu , No. 129, key adsorbed residue . High ligand density , a strong adsorption of lysozyme , but itself conformational changes are more obvious . The replacement process , the replacement agent and the ligand of the hydrophobic interaction is stronger than the lysozyme, and there aggregation - dispersion homeostasis , can promote the lysozyme in the matrix plane . The displacer BC belongs to the chemical selective displacer , and TC replacement is better than CC . The better effect of the replacement of the replacement of high concentrations of agent , while the high ligand density may cause the the substitution agent with the ligand-binding too firmly eluting . The study explains the molecular mechanism of HCIDC ligand density , the type and concentration of the displacer impact on the performance of the chromatographic separation , help guidance chromatography process optimization as well as the rational design of ligand and displacer .
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