Recent advances in the determination of elemental impurities in pharmaceuticals - Status, challenges and moving frontiers

Elemental impurities have been regulated in pharmaceutical products for many decades. Metal impurities such as As, Cd, Cu, Pb, Hg, V and Pt in pharmaceuticals and drugs are known to originate from sources like raw materials, catalysts, metal reagents and even manufacturing equipments. An account of the recent changes implemented by the European Pharmacopoeia (EP), the United States Pharmacopoeia (USP) and other International regulatory bodies for constraining inorganic impurities in pharmaceutical and drug products coupled with new strategies to be adopted for heavy metal analyses is presented. Rapid methods of screening during quality control operations, and a brief account of classical spectrophotometry and the role of instrumental techniques such as atomic absorption spectrometry (AAS), X-ray fluorescence spectrometry (XRF), instrumental neutron activation analysis (INAA), inductively coupled plasma atomic emission spectrometry (ICP-AES) and the inductively coupled plasma mass spectrometry (ICP-MS) for the accurate determination of inorganic impurities in pharmaceutical materials are presented.