Technical Information

Overview of method development for isolation/purification Analytical scale conditions Loading Scale-up Preparative separation conditions Effective preparative separation technique Examples of preparative purification


4. Method optimization on the preparative scale

Preparative separation conditions are optimized with analytical scale column packed with the selected particle size.

Separation method optimization

When the particle size used in the preparative separation is larger than that used in the analytical scale, the required separation may not be achieved due to lower column efficiencies. The separation may be improved by adjusting the mobile phase composition or reducing the linear velocity. If the separation still doesn’t improve, the column length or the particle size needs to be changed.

Mobile phase condition optimization

Loading study (300 X 10 mmI.D.)

Preparative system evaluation

It is essential to make sure that the required flow rate and pressure are suitable for the specifications of the preparative LC system. The same linear velocity used in analytical scale should be used to achieve the same resolution on the preparative column. Under the same linear velocity, operating pressure on the preparative column is as almost same as that on the analysis column. If the column pressure exceeds the limit of the system, the flow rate or column length needs to be reduced.

Performing preparative separation

A preparative separation should be performed and the recovery and purity are evaluated.