title: Effect of polymer containing a naphthyl-alanine derivative on the separation selectivity for aromatic compounds in temperature-responsive chromatography.
abstract: A novel polymer-grafted stationary phase of high-performance liquid chromatography (HPLC) was developed, utilizing a temperature-responsive polymer containing an aromatic moiety. Firstly, we synthesized novel functional polymer poly(N-isopropylacrylamide-co-N-acryloyl-3-(2-naphthyl)-L-alanine methyl ester) [poly(NIPAAm-co-Nap)], which has temperature-responsiveness and selective retention of aromatic compounds by an intermolecular π-π interaction. The polymer exhibited a significant reversible phase transition from hydrophilic to hydrophobic in the vicinity of its lower critical solution temperature. Employing the developed polymer-grafted silica column, temperature-responsive chromatography was conducted using water as a sole mobile phase. A comparison with a conventional ODS column or a homogeneous PNIPAAm-grafted silica column showed that the retention of aromatic compounds was dramatically increased on the poly(NIPAAm-co-Nap)-grafted stationary phase. Introducing the naphthyl-alanine derivative caused a significant effect on the retention selectivity for aromatic compounds.
authors.affiliation: Faculty of Pharmacy, Keio University, 1-5-30 Shibakoen, Minato-ku, Tokyo 105-8512, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Nishio
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Kanazashi
authors.forename: Akari
authors.initials: A
authors.lastname: Nojima
authors.forename: Hideko
authors.initials: H
authors.lastname: Kanazawa
authors.forename: Teruo
authors.initials: T
authors.lastname: Okano
mesh_terms: D000178:Acrylamides / Q000737:chemistry*; D000180:Acrylic Resins; D000409:Alanine / Q000031:analogs & derivatives* / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation* / Q000379:methods; D006841:Hydrocarbons, Aromatic / Q000302:isolation & purification*; D057927:Hydrophobic and Hydrophilic Interactions; D009281:Naphthalenes / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D013256:Steroids / Q000302:isolation & purification*; D013696:Temperature
chemical_list: D000178:Acrylamides; D000180:Acrylic Resins; D006841:Hydrocarbons, Aromatic; D009281:Naphthalenes; D011108:Polymers; D013256:Steroids; C052970:poly-N-isopropylacrylamide; D000409:Alanine; C513002:2-naphthylalanine