title: Adsorption of aqueous organic mixtures on a chiral stationary phase with bound antibiotic eremomycin.
abstract: The adsorption of two typical hydro-organic mobile phases, with methanol and acetonitrile as the organic component, on an antibiotic based chiral stationary phase (CSP) Nautilus-E was studied by the minor perturbation method. In both cases, the excess adsorption of water was positive over a wide range of concentrations from 0 to ∼75 or 90 mol% for MeOH or MeCN containing mobile phases, respectively. Such hydrophilic properties of the CSP were attributed to multiple polar functional groups of the chiral ligand and to the residual silanol groups of the silica support. The adsorbed phase was found to be thinner for H₂O-MeOH (∼1.1Å) and thicker for H₂O-MeCN (∼9.4Å). The measurements of the column hold-up volume by different methods allowed us to suggest a model of the adsorbed phase consisting of the volume between bound chiral selectors inaccessible to large size molecules and of the stagnant layer of the mobile phase adsorbed on the external surface of the chiral selectors.
authors.affiliation: Perm National Research Polytechnic University, 29 Komsomolski Al., Perm 614990, Russia.
authors.forename: Yuliya K
authors.initials: YK
authors.lastname: Nikitina
authors.affiliation: Jamia Millia Islamia (Central University), Jamia Nagar, New Delhi 110025, India.
authors.forename: Imran
authors.initials: I
authors.lastname: Ali
authors.affiliation: Perm National Research Polytechnic University, 29 Komsomolski Al., Perm 614990, Russia. Electronic address: asninld@mail.ru.
authors.forename: Leonid D
authors.initials: LD
authors.lastname: Asnin
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D000327:Adsorption; D000900:Anti-Bacterial Agents / Q000737:chemistry*; D006020:Glycopeptides / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D000432:Methanol / Q000737:chemistry; D012822:Silicon Dioxide; D013237:Stereoisomerism; D014867:Water / Q000737:chemistry
chemical_list: D000097:Acetonitriles; D000900:Anti-Bacterial Agents; D006020:Glycopeptides; D014867:Water; C053759:eremomycin; D012822:Silicon Dioxide; D000432:Methanol; C032159:acetonitrile
keywords: Adsorption thermodynamics; Chiral stationary phase; Eremomycin; Excess adsorption