Sometimes an impurity has to be isolated to carry out some studies requiring the availability of the pure chemical compound:
• When additional structural analysis are required to confirm a hypothesized chemical structure of an unidentified impurity, such as NMR, GC-MS, or FTIR.
• A standard of the impurity required for QC analytical methods for impurity monitoring after drug manufacturing.
• Or when a new impurity must be biologically qualified because it is present at concentrations reaching 0.15% in the drug substance or pharmaceutical product.
Automated Preparative Liquid Chromatography allows the chromatographic fractionation to isolate the impurity in sufficient quantities reaching high purity values.