title: Evaluation of ionic liquids-coated carbon nanotubes modified chiral separation system with chondroitin sulfate E as chiral selector in capillary electrophoresis.
abstract: Nanoparticles (NPs) and ionic liquids (ILs) have been extensively studied and have aroused considerable interest in separation science; however, the employment of ILs-dispersed NPs as buffer modifiers for CE chiral separation has not been previously studied. In this work, we describe a new CE method using ILs dispersed multi-walled carbon nanotubes (ILs-MWNTs) as a modifier for enantioseparation with a polysaccharide, chondroitin sulfate E (CSE), as the chiral selector. As observed, significantly improved separations, including better enantioselectivity and improved peak shapes, were obtained in the ILs-MWNTs modified separation system for all drug enantiomers compared to the single CSE system. Several parameters affecting the enantioseparation, such as the choice of ILs and carbon nanoparticles, ILs-MWNTs concentration, chiral selector concentration, buffer pH and applied voltage, were systematically investigated. Satisfactory separations were achieved when 2.4μg/mL ILs-MWNTs were introduced into the 20mM Tris/H3PO4 buffer solution containing 2.5% CSE at pH 2.8-3.4 with a 15kV applied voltage. A brief mechanism of the enhanced enantioseparation capability of the ILs-MWNTs modified chiral separation system was also discussed.
authors.affiliation: Department of Analytical Chemistry, China Pharmaceutical University, Nanjing 210009, PR China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Analytical Chemistry, China Pharmaceutical University, Nanjing 210009, PR China; Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), China Pharmaceutical University, Nanjing 210009, PR China; State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, PR China. Electronic address: du_yingxiang@126.com.
authors.forename: Yingxiang
authors.initials: Y
authors.lastname: Du
authors.affiliation: College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, PR China.
authors.forename: Shuaijing
authors.initials: S
authors.lastname: Du
mesh_terms: D002021:Buffers; D002809:Chondroitin Sulfates / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D052578:Ionic Liquids; D037742:Nanotubes, Carbon; D004364:Pharmaceutical Preparations / Q000737:chemistry / Q000302:isolation & purification; D013237:Stereoisomerism
chemical_list: D002021:Buffers; D052578:Ionic Liquids; D037742:Nanotubes, Carbon; D004364:Pharmaceutical Preparations; D002809:Chondroitin Sulfates
keywords: Capillary electrophoresis; Carbon nanotubes; Chondroitin sulfate E; Enantioseparation; Ionic liquids; Ionic liquids-coated carbon nanotubes