Active Flow Technology (AFT) is the term that encompasses a range of new
chromatography columns that are designed to eliminate wall effects, minimise solute
band broadening due to radial heterogeneity and decrease the peak volume of eluting
components. This is achieved through the use of novel endfittings which separate the
peripheral flow from the central flow. These endfittings have been used in two different
configurations, namely with the endfitting solely at the outlet of the column, referred to as
parallel segmented flow (PSF), or with the endiftting placed at both the outlet and the inlet
of the column, referred to as curtain flow (CF). Figure 1 shows a diagram of the endfitting
and the two possible configurations.