Determination of tungsten in bulk drug substance and intermediates by ICP-AES and ICP-MS

A quick and sensitive method has been developed and validated for the deter mination of tungsten in bulk drug substance and intermediates using either Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) or Induct ively Coupled Plasma Mass Spectrometry (ICP-MS). Sample preparation is by d irect dissolution with a 80:20 (v/v) concentrated nitric acid:deionized wat er mixture and avoids labor intensive and potentially hazardous digestion t echniques. Excellent agreement was found between ICP-AES and ICP-MII result s and between Merck results and Microwave Induced Plasma Mass Spectrometry (MIP-MS) results provided by an independent raw material vendor. (C) 1999 E lsevier Science B.V. All rights reserved.