title: Program for the interpretive optimization of two-dimensional resolution.
abstract: The challenge of fully optimizing LC×LC separations is horrendous. Yet, it is essential to address this challenge if sophisticated LC×LC instruments are to be utilized to their full potential in an efficient manner. Currently, lengthy method development is a major obstacle to the proliferation of the technique, especially in industry. A program was developed for the rigorous optimization of LC×LC separations, using gradient-elution in both dimensions. The program establishes two linear retention models (one for each dimension) based on just two LC×LC experiments. It predicts LC×LC chromatograms using a simple van-Deemter model to generalize band-broadening. Various objectives (analysis time, resolution, orthogonality) can be implemented in a Pareto-optimization framework to establish the optimal conditions. The program was successfully applied to a separation of a complex mixture of 54 aged, authentic synthetic dyestuffs, separated by ion-exchange chromatography and ion pair chromatography. The main limitation experienced was the retention-time stability in the first (ion-exchange) dimension. Using the PIOTR program LC×LC method development can be greatly accelerated, typically from a few months to a few days.
authors.affiliation: University of Amsterdam, van't Hoff Institute for Molecular Sciences, Analytical-Chemistry Group, Science Park 904, 1098 XH Amsterdam, The Netherlands; TI-COAST, Science Park 904, 1098 XH Amsterdam, The Netherlands. Electronic address: B.W.J.Pirok@uva.nl.
authors.forename: Bob W J
authors.initials: BW
authors.lastname: Pirok
authors.affiliation: University of Amsterdam, van't Hoff Institute for Molecular Sciences, Analytical-Chemistry Group, Science Park 904, 1098 XH Amsterdam, The Netherlands; Departament de Química Analítica, Universitat de València, c/Dr. Moliner 50, Burjassot 46100, Spain.
authors.forename: Sandra
authors.initials: S
authors.lastname: Pous-Torres
authors.affiliation: University of Amsterdam, van't Hoff Institute for Molecular Sciences, Analytical-Chemistry Group, Science Park 904, 1098 XH Amsterdam, The Netherlands; Departament de Química Analítica, Universitat de València, c/Dr. Moliner 50, Burjassot 46100, Spain.
authors.forename: Cassandra
authors.initials: C
authors.lastname: Ortiz-Bolsico
authors.affiliation: University of Amsterdam, van't Hoff Institute for Molecular Sciences, Analytical-Chemistry Group, Science Park 904, 1098 XH Amsterdam, The Netherlands.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Vivó-Truyols
authors.affiliation: University of Amsterdam, van't Hoff Institute for Molecular Sciences, Analytical-Chemistry Group, Science Park 904, 1098 XH Amsterdam, The Netherlands.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Schoenmakers
mesh_terms: D002852:Chromatography, Ion Exchange / Q000379:methods* / Q000592:standards*; D004396:Coloring Agents / Q000302:isolation & purification; D012984:Software; D013997:Time Factors
chemical_list: D004396:Coloring Agents
keywords: LC×LC; Pareto-optimality; interpretive optimization; method development; retention prediction; synthetic dyes