title: Simplex optimization of ion-pair reversed-phase high performance liquid chromatographic analysis of some heavy metals.
abstract: The sequential simplex algorithm was used to optimize the ion-pair reversed phase high performance liquid chromatographic (IP-RPHPLC) analysis of 4-(2-pyridylazo)resorcinol (PAR) chelates of Co(II), Ni(II) and Cr(III). A chromatographic response function (CRF) which included the number of peaks, the resolution between adjacent peaks, a specified analysis time, and the individual retention times relative to a minimum retention time, was calculated to evaluate the quality of the individual chromatograms. The optimum conditions for the three experimental parameters were 28.6% acetonitrile in the mobile phase, 3.0 mmol l(-1) concentration of acetate buffer at pH 6.0, and 5.2 mmol l(-1) tetrabutylammonium bromide (TBABr). Optimum conditions were achieved in only 19 experiments. The order of elution was Co(II)PAR, Cr(III)PAR and Ni(II)PAR, respectively, with an analysis time of 15 min.
authors.affiliation: Department of Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand.
authors.forename: Supalax
authors.initials: S
authors.lastname: Srijaranai
authors.forename: Rodjana
authors.initials: R
authors.lastname: Burakham
authors.forename: Richard L
authors.initials: RL
authors.lastname: Deming
authors.forename: Tipwan
authors.initials: T
authors.lastname: Khammeng