MasterNanosciences, nanotechnologies

Many biologically-active compounds such as drugs, agrochemicals or food additives, have chiral structures and their physiological properties usually depend on this chirality. Hence, chiral resolution by HPLC has significantly been developed and a variety of chiral columns packed with polysaccharidic chiral selectors are commercialized. It has been assumed that the chiral recognition by these chiral selectors was due to specific interactions with enantiomers through hydrogen bonding, dipole-dipole interaction, or p–p stacking. However, the molecular mechanisms remain poorly understood. To approach this question, this project aims at combining experimental study (crystallographic analysis) and theoretical approach (molecular modeling) of polysaccharidic chiral selectors such as cellulose/amylose dimethylphenycarbamates to elucidate the mechanism of chiral resolution.

The polysaccharidic chiral selectors will be crystalized with/without chiral active molecules and their crystal structures will be analyzed by imaging techniques (e.g. confocal and transmission electron microscopy) and electron/X-ray diffraction (cf. Figure 1). GROMACS software will be used for the modeling. The internship involves:
1) rational choice of force field,
2) construction of molecule description file
3) running simulation with the polysaccharidic chiral selectors
4) analysis of trajectory files, typically extracting statistics of conformation, residence time of the small molecule in different loci etc.