This case study discusses two approaches taken when different clients had a requirement for determination of the level of known process impurities in multiple batches of Active Pharmaceutical Ingredient (API).

In both cases the detection of the process impurity presented technical challenges due to the inability of most common specific techniques (Liquid Chromatography Mass Spectrometry, Gas Chromatography Mass Spectrometry or Inductively Coupled Plasma Mass Spectrometry) to adequately detect the impurity.