Carbon cartridges and their use as a purification step in pharmaceutical API processes

Carbon cartridges from two suppliers have been tested in two pharmaceutical API processes. In process 1, the aim was to reduce an impurity (A) from ∼3% to at least less than 2%. In process 2, the aim was to reduce an unidentified low-level, red coloured impurity (B) to such levels that the Active Pharmaceutical Ingredient (API) would be white to off-white in colour.