LAUSR

In HPLC today, separation tasks are getting more and more complex. Often very heterogeneous mixtures containing hundreds of components have to be separated. If samples have such a complexity it is not possible to separate via standard HPLC or UHPLC alone. In these cases, peak capacity needs to be increased drastically. The typical and best approach to handle peak capacity issues is multidimensional HPLC and in-depth optimization of selectivity. However, this approach is an excellent choice only if the developed methods are used over a long period of time. If samples of extreme complexity only need to be separated once, method development for a multidimensional HPLC is too time consuming and expensive. An easy one-dimensional approach, creating peak capacity far beyond UHPLC is, therefore, presented in the current publication. Several strategies for the separation of complex mixtures are illustrated and some typical examples are shown. In addition to very long columns packed with conventional 5 μm superficial porous materials, shorter columns with circular flow (recycling chromatography) are investigated.Graphical Abstract