HPLC IMPURITY PROFILE ANALYSES OF PHARMACEUTICAL SUBSTANCES USING UV PHOTODIODE-ARRAY DETECTION

High performance liquid chromatography (HPLC) is routinely used for de termination of both assay and impurities in both bulk active and formu lated drug products. Impurity profile analyses are required to demonst rate the ability to detect a wide range of impurities which may occur in pharmaceuticals. However, most impurity profile methods do not addr ess the potential of co-elution of impurities with product peaks. UV p hotodiode array detection (PDA) evaluates the UV and/or the UV/VIS spe ctrum of an eluting species to determine spectral homogeneity. If vari ations in tile spectrum are observed, the possibility of a co-eluting impurity must be addressed. By establishing consistent evaluations HPL C-PDA can be used to more accurately assess impurity levels and provid e analyses with much higher informational content.