title: Chiral HPLC Separation and Modeling of Four Stereomers of DL-Leucine-DL-Tryptophan Dipeptide on Amylose Chiral Column.
abstract: Chiral high-performance liquid chromatography (HPLC) separation and modeling of four stereomers of DL-leucine-tryptophan DL-dipeptide on AmyCoat-RP column are described. The mobile phase applied was ammonium acetate (10 mM)-methanol-acetonitrile (50:5:45, v/v). The flow rate of the mobile phases was 0.8 mL/min with UV detection at 230 nm. The values of retention factors for LL-, DD-, DL-, and LD- stereomers were 2.25, 3.60, 5.00, and 6.50, respectively. The values of separation and resolution factors were 1.60, 1.39, and 1.30 and 7.76, 8.05, and 7.19. The limits of detection and quantitation were ranging from 1.0-2.3 and 5.6-14.0 μg/mL. The simulation studies established the elution orders and the mechanism of chiral recognition. It was seen that π-π connections and hydrogen bondings were the main forces for enantiomeric resolution. The reported chiral HPLC method may be applied for the enantiomeric separation of DL-leucine-DL-tryptophan in unknown matrices. Chirality 28:642-648, 2016. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Department of Pharmacognosy, College of Pharmacy, King Saud University, Riyadh, Kingdom of Saudi Arabia.
authors.forename: Mohammed F
authors.initials: MF
authors.lastname: Alajmi
authors.affiliation: Department of Pharmacognosy, College of Pharmacy, King Saud University, Riyadh, Kingdom of Saudi Arabia.
authors.forename: Afzal
authors.initials: A
authors.lastname: Hussain
authors.affiliation: Department of Chemistry, Jamia Millia Islamia, New Delhi, India.
authors.forename: Mohd
authors.initials: M
authors.lastname: Suhail
authors.affiliation: Department of Chemistry, Jamia Millia Islamia, New Delhi, India.
authors.forename: Sofi Danish
authors.initials: SD
authors.lastname: Mukhtar
authors.affiliation: Department of Chemistry, Jamia Millia Islamia, New Delhi, India.
authors.forename: Dibya Ranjan
authors.initials: DR
authors.lastname: Sahoo
authors.affiliation: Perm National Research Polytechnic University, Perm, Russia.
authors.forename: Leonid
authors.initials: L
authors.lastname: Asnin
authors.affiliation: Department of Chemistry, Jamia Millia Islamia, New Delhi, India.
authors.forename: Imran
authors.initials: I
authors.lastname: Ali
mesh_terms: D000688:Amylose / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D004151:Dipeptides / Q000737:chemistry / Q000302:isolation & purification*; D007930:Leucine / Q000737:chemistry / Q000302:isolation & purification*; D057230:Limit of Detection; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013237:Stereoisomerism; D014364:Tryptophan / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D004151:Dipeptides; D014364:Tryptophan; D000688:Amylose; D007930:Leucine
keywords: AmyCoat-RP; DL-Leucine-DL-tryptophan; HPLC; chiral resolution; dipeptide; modeling studies