kogason2010 Lab

Scale a method to a new column

Moving to a different column diameter or length? Keep the same linear velocity and these are the numbers that change.

Flow scales with the square of the diameter. For the same load relative to column volume, injection volume scales with diameter² × length. At the same linear velocity, run time and backpressure scale with length, and resolution with its square root. Real columns differ in particle size and chemistry, so treat these as starting points.

Typical separation

The same water sample, run once on an anion-exchange column and once on a cation-exchange column.

Illustrative chromatogram showing a typical elution order. Actual retention times depend on the column, eluent and conditions.