title: Analysis of melatonin using a pH- and temperature-responsive aqueous chromatography system.
abstract: A new method for the qualitative and quantitative analysis of an intracerebral hormone, such as melatonin, has been proposed, utilizing newly designed copolymers that include ion-exchange groups. These copolymers responded to both the temperature and the pH, and the copolymers were modified with cross-linked hydrogel applied onto aminopropyl silica beads. The products were evaluated as HPLC packing materials for a pH- and temperature-responsive chromatography. The property of the surface of the stationary phase was altered from hydrophilic to hydrophobic, and from charged to non-charged by changes in both the temperature and the pH. In the chromatographic system, we investigated how to change the retention of melatonin by varying the temperature. A pH- and temperature-responsive chromatography is expected to be useful for the separation of pharmaceuticals and biomolecules.
authors.affiliation: Department of Physical Pharmaceutical Chemistry, Kyoritsu University of Pharmacy, Tokyo, Japan.
authors.forename: Eri
authors.initials: E
authors.lastname: Ayano
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Masahito
authors.initials: M
authors.lastname: Kanezawa
authors.forename: Chikako
authors.initials: C
authors.lastname: Sakamoto
authors.forename: Yuko
authors.initials: Y
authors.lastname: Morita-Murase
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Nagata
authors.forename: Hideko
authors.initials: H
authors.lastname: Kanazawa
authors.forename: Akihiko
authors.initials: A
authors.lastname: Kikuchi
authors.forename: Teruo
authors.initials: T
authors.lastname: Okano
mesh_terms: D000180:Acrylic Resins; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D007475:Ion Exchange Resins; D008550:Melatonin / Q000032:analysis*; D012701:Serotonin / Q000031:analogs & derivatives / Q000302:isolation & purification; D013696:Temperature; D014364:Tryptophan / Q000302:isolation & purification
chemical_list: D000180:Acrylic Resins; D007475:Ion Exchange Resins; C052970:poly-N-isopropylacrylamide; D012701:Serotonin; D014364:Tryptophan; D008550:Melatonin; C006389:N-acetylserotonin