{Reference Type}: Journal Article
{Title}: Binding modes identification through molecular dynamic simulations: A case study with carnosine enantiomers and the Teicoplanin A2-2-based chiral stationary phase.
{Author}: Sardella R;Ianni F;Cossignani L;Aldini G;Carotti A;
{Journal}: J Sep Sci
{Volume}: 43
{Issue}: 9
{Year}: May 2020
{Factor}: 3.614
{DOI}: 10.1002/jssc.202000092
{Abstract}: In the present study, an in silico methodology able to define the binding modes adopted by carnosine enantiomers in the setting of the chiral recognition process is described. The inter- and intramolecular forces involved in the enantioseparation process with the Teicoplanin A2-2 chiral selector and carnosine as model compound are successfully identified. This approach fully rationalizes, at a molecular level, the (S) < (R) enantiomeric elution order obtained under reversed-phase conditions. Consistent explanations were achieved by managing molecular dynamics results with advanced techniques of data analysis. As a result, the time-dependent identification of all the interactions simultaneously occurring in the chiral selector-enantiomeric analyte binding process was obtained. Accordingly, it was found that only (R)-carnosine is able to engage a stabilizing charge-charge interaction through its ionized imidazole ring with the carboxylate counter-part on the chiral selector. Instead, (S)-carnosine establishes intramolecular contacts between its ionized functional groups, that limit its conformational freedom and impair the association with the chiral selector unit.