Performance limits and kinetic optimization of parallel and serially connected multi-column systems spanning a wide range of efficiencies for liquid chromatography

► The possibilities of multi-column systems to cover a range of efficiencies are investigated. ► Serially-connected and parallel-connected column systems are compared. ► The serial connection mode offers a better compromise between average speed and total required column length than the parallel connection. ► The best possible serial connection system can get within 15-25% of the Knox & Saleem-speed limit at 1200 bar. ► The construction of wide-efficiency range systems is one of the application areas wherein the advantages of UHPLC-conditions will be most fully realized.