There is an increasing need for fast and ultra-fast separation methods with good efficiency and resolution. Ultra performance liquid chromatography (UPLC) has become a widely used technique,
which takes full advantages of chromatographic principles to perform separation, using short columns packed with smaller particles (sub-2 lm). This has led to a shorter analysis time, improved peak efficiency (peak width), better resolution and decreased use of solvents compared with conventional high-performance
liquid chromatography (HPLC). Moreover, the UPLC system enables the detection of analytes at very low concentrations because of the improved signal-to-noise ratio. The injection volume in UPLC can be significantly reduced without loss of sensitivity. However, the use of short columns (50–100 mm), packed with sub-2 lm particles in conventional liquid chromatography (LC), are limited by increased column back-pressure (>40 MPa) which is not compatible with conventional instrumentation. The necessity of
using instrumentation dedicated to UPLC is a limitation of this technique.