Punit M Patel

As per ICH guideline impurity may be defined as any component of drug product that is not the drug substance or an excipient. Now a day apart from purity profile there are an increasing essentiality of impurity profile by regulatory agency. Different regulatory agencies like ICH,USFDA, TGA, etc. work on control and identification of impurities in pharmaceutical dosage forms. To identify and characterize impurities are essential for establishing the biological safety of an pharmaceutical dosage forms. The various pharmacopoeias like IP, BP, USP, etc. were allowed certain limits of impurities in pharmaceutical dosage forms. This review article mainly focuses on various methods available to identify and characterize impurities in pharmaceutical dosage forms. Among all, the most specific techniques are NMR, MASS, GC-MS, LC-MS, HPLC-DAD-MS, LC-MS-MS, HPLC-DAD-NMR-MASS, Capillary electrophoresis, Mass and Flash chromatography. Key words: Impurities, identification, HPLC-DAD-MS.