Measurement of Elemental Impurities in Pharmaceutical Products by ICP-AES and ETAAS

Introduction

Electrothermal atomic absorption spectrometry (ETAAS) and inductively coupled plasma atomic emission spectroscopy (ICP-AES) are widely used as trace metal analytical methods. In addition, they are also effective for analysis of metallic impurities in pharmaceutical products and their raw materials. In Japan, the guidelines for impurities in new drug substances (Notification No. 1216001, issued by Evaluation and Licensing Division, Pharmaceutical and Food Safety Bureau; revised December 16, 2002) specify that residual metallic catalysts are to be analyzed according to the test method specified in the Japanese Pharmacopoeia or another appropriate method, and that evaluation be conducted in the development stage. Furthermore, the first revision of the 16th Japanese Pharmacopoeia (September 27, 2012) includes inductively coupled plasma atomic emission spectroscopy (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS) as analytical methods under the general test methods. In addition, The United States Pharmacopeia (USP) added the general chapter <232> Elemental Impurities – Limits, which sets the permissible limits for the so- called Big Four elements (lead, cadmium, arsenic, mercury). Also, the preparation procedures and analytical methods specified in USP <233> Elemental Impurities – Procedures include those for ICP-MS and ICP-AES, respectively. Here we introduce examples of analysis of metallic impurities in the commonly used anti-inflammatory analgesic acetylsalicylic acid (aspirin) using ICP-AES and ETAAS.

March 18, 2013 GMT