According to ICH Q6B guidelines [3], impurities in biological products can be classified as process-related and product-related. Process-related impurities include those that are derived from the manufacturing process (e.g., cell substrates, cell culture media components, or downstream processing); product-related impurities in the drug substance are molecular variants with properties different from those of the desired product formed during manufacture and/or storage. The general approach to the characterization of these impurities is to isolate sufficient quantity and then apply commonly used techniques for characterization. SSCI offers a full complement of analytical techniques for the isolation and characterization of process and product-related impurities:
- Isolation and purification by LC: Reversed-phase, Ion exchange, Size exclusion
- Identification: Mass Spectrometry (ESI-Triple Quad, MALDI-TOF, Q-TOF), NMR (1D and 2D), FTIR, Raman, and UV-Vis spectroscopy, N-terminal Edman sequencing, LC-MS/MS de novo sequencing, peptide mapping, disulfide bond mapping, amino acid analysis
