Computer simulation of isocratic retentions of alkylketones using gradient data

Computerized design of separation strategies by reversed-phase liquid chromatography: development of DryLab software

The development of DryLab software is a special achievement in analytical HPLC which took place in the last 16 years. This paper tries to collect some of the historical mile stones and concepts. DryLab, being always subject to change according to the needs of the user, never stopped being developed. Under the influence of an ever changing science market, the DryLab development team had to consider not just scientific improvements, but also new technological achievements, such as the introduction of Windows 1.0 and 3.1, and later Windows NT and 2000. The recent availability of new 32-bit programming tools allowed calculations of chromatograms to be completed more quickly so as to show peak movements which result for example from slight changes in eluent pH. DryLab is a great success of interdisciplinary and intercontinental cooperation by many scientists.

Combined use of temperature and solvent strength in reversed-phase gradient elution. I. Predicting separation as a function of temperature and gradient conditions

It has been shown previously that computer simulation based on two initial experiments can predict separation in reversed-phase gradient elution as a function of gradient conditions (gradient steepness, gradient range and gradient shape) and column conditions (column length, flow-rate and particle size). The present study extends this capability for changes in temperature. Four initial experiments (two different gradient times, two different temperatures) provide input data that allow predictions of separation as a function of temperature as well as gradient and column conditions. A semi-empirical relationship, tR = a + bT, is able to relate gradient retention time tR to column temperature T (other conditions constant). The accuracy of this approach has been evaluated for 102 solutes and a variety of experimental conditions, including the use of five different HPLC instruments (four different models).