New developments in automated PrepLCMS extends the robustness and utility of the method for compound library analysis and purification

New developments in the high throughput purification of combinatorial libraries by automated preparative LC-MS is presented. To facilitate high speed purifications at the multimilligram level, short columns operated at ultra high flow rates were incorporated. In order to match the linear velocity of the short analytical columns for high speed separations (operated at 4.0 mL/min), it was required to operate the preparative columns at flow rates in excess of 70 mL/min. For chromatographically well-behaved compounds, analytical LC-MS analyses and preparative LC-MS analyses could be achieved in as little as 5 min. For compounds exhibiting poor chromatographic peak shapes and/or for compound mixtures requiring higher resolution separations, slightly longer preparative LC-MS analysis times were required (8-10 min/sample).