Patent ID: 8117901

Claim:
A method of determining the concentration of a chromatographic medium in a liquid slurry, comprising: providing a column ( 1 ) having a top end ( 3 ) and a bottom end ( 2 ) and adapted to retain a chromatographic medium therein; introducing a defined volume of the slurry ( 15 ) into the column ( 1 ); providing a liquid flow through the column ( 1 ) from the top end to the bottom end of the column to settle the chromatographic medium in the column; measuring the bed height of the consolidated chromatographic medium or a value related thereto; and determining from the measured bed height or value related thereto the concentration, or a value related to the concentration of the chromatographic medium in the slurry; wherein prior to settling the chromatographic medium, the medium is subjected to a wash step in the column ( 1 ).