PhyNexus’ proprietary Dual Flow Chromatography (DFC) results in molecular separations by use of bi-directional flow (back-and-forth) of a mobile phase across a stationary phase.  Basic chromatographic principals control the separations, however, the bi-directional flow drives interactions to high loading equilibrium regardless of kinetic rate constants (linear and absolute fluid flow rates, column bed diameter, length and geometry, packing uniformity or column channeling, column dead volumes, or amount of stationary phase in the column). Interactions (reactions within the column) can be controlled and equilibrium shifted by controlling reagent concentrations while limiting reagent volumes.


DFC offers distinct advantages over spin columns, magnetic beads, plates and other unidirectional technologies:  reactions got to completion which means DFC is to scale, is more reproducible, can operate easily in parallel, etc.

Reproducible, high recovery

DFC is extremely well-suited for small sample sizes, driving quickly to high loading equilibrium.  Very high concentrations of recovered protein can be achieved from very small sample sizes (as small as 5 μL) due to column design, software control and bi-directional versus unidirectional flow.   Increased time of interaction (bi-directional flow) compensates for slow reaction kinetics and results in capture at high loading equilibrium.


DFC is extremely efficient in the use of reagents, creating additional benefits.  Very small molar excess of reagents is needed to achieve high loading equilibrium, even when using small liquid volumes.  Efficient use of reagents in small volumes allows for multivariate control of purifications, and reaction equilibriums can be easily shifted toward product with less reagent.


On-column derivatization reactions can be done to functionalize columns to perform efficient affinity pull down or enzyme reactions.


DFC is uniquely suited for high-throughput automation due to the high yields from small sample sizes and compatibility with existing robotic liquid handling systems.  Due to its ability to yield high concentrations from small sample sizes, DFC is plug-and-play for virtually all major 8-, 12- or 96-column robotic liquid handling system;

Separation condition optimization

DFC can dramatically reduce the time and labor required to perform rapid method development, design of experiments (DOE), quality by design (QbD), or high-throughput chromatographic purification. 12-column parallel robotic pipette head operating with a 96-well plate can evaluate, for example, 8 conditions (sample loading, column wash, elution, etc.) or 16 conditions with two plates. Parallel optimization experiments can be performed in hours versus weeks or months for unidirectional and non-parallel flow processes.

Scale up for preparation separation or manufacturing

DFC columns accurately predict the performance of preparative and manufacturing columns.  The increased time of interaction of DFC accurately mimics and predicts the selectivity at high loading equilibrium of large diameter preparative and manufacturing columns, including Continuous Chromatography