Abstract:

This study presents a molecular dynamics simulation of protein separation by reverse phase liquid chromatography（RPLC）at all-atom level，using silica gel surface with C₄ compounds and cytochrome C as representative adsorbent and protein，respectively. The conformational transition of cytochrome C was monitored during the aqueous adsorption onto the adsorbent and elution with methanol. It was shown that during the adsorption，in which protein was attracted to the adsorbent surface，a simultaneous exclusion of water molecules occurred both at the adsorbent surface and the protein. A conformational transition of the protein conformation that led to the exposure of the hydrophobic amino acid residues，as compared to its native conformation in aqueous phase，was also displayed. During the elution by methanol，the replacement of water molecule by methanol occurred on both the surface of adsorbent and the adsorbed protein. As a result，the adsorbed protein was replaced by methanol. Above-mentioned simulation results reproduced the preferential hydration mechanism of the adsorption by RPLC and provided a molecular insight into the interaction among protein，adsorbent and the solvents at all-atom level，which is helpful for the design of new adsorbent and the optimization of RPLC process.