Energy Dispersive X-ray Fluorescence Spectroscopy

Control of Elemental Impurities in Pharmaceuticals In the pharmaceutical industry, the analysis of elemental impurities is necessary to ensure the safety of pharmaceuticals. In December 2014, the "Guideline for Elemental Impurities" (Q3D) was issued by the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH), consisting of representatives from Europe, the U.S. and Japan. In Japan, the "Guideline for Elemental Impurities in Drug Products" (PFSB/ELD Notification 0930 #4 from the Ministry of Health, Labour and Welfare) was issued, and will be applied to new drug products submitted for approval after April 1 2017. For 24 elements categorized in Class 1 to Class 3, residual quantities in pharmaceutical drug products must be controlled within permissible limits. Although ICP-AES and ICP-MS are used for precise analysis of elemental impurities, X-ray fluorescence spectrometers can be used as an alternative analysis method. This is because they can quantitatively and qualitatively analyze a variety of elements nondestructively, and without chemical pretreatment, unlike ICP-AES and ICP-MS systems. The X-ray fluorescence spectrometry has been adopted as a general method of analysis in the U.S Pharmacopeia and the European Pharmacopoeia. (USP<735>, Ph.Eur.2.2.37)