Identification in drug quality control and drug research

• Identification of bulk drugs and the active ingredients in formulations.
• Identification is based on IR and UV spectroscopies, HPLC and TLC.
• Impurities and degradants are identified by HPLC-UV, HPLC-MS and NMR spectroscopy.
• Identification in drug research and the fight against counterfeit drugs.

Identification is an important step in the quality control of drugs and the research for new drugs. First, this review discusses the identification of bulk drugs and the active ingredients in formulations, based mainly on pharmacopoeial tests. The most important methods for this purpose are infrared (IR) and, to a lesser extent, ultraviolet (UV) spectroscopy, as well as retention matching with standards using high-performance liquid chromatography (HPLC) and thin-layer chromatography (TLC). The identification of impurities and degradants is based mainly on HPLC-UV, HPLC-mass spectrometry (HPLC-MS) and nuclear magnetic resonance (NMR) spectroscopies. The above methods are also used for identification purposes in drug research. The use of MS and NMR in the research for large-molecule drugs of biotechnological origin and natural products, mainly of plant origin, with special respect to traditional Chinese (and Indian) medicines is also discussed. The review concludes with the identification aspects of the fight against counterfeit drugs.