Application Editorial

How to Measure Moisture Content in Pharmaceuticals

Application Editorial

Guidance on How to Measure the Moisture Content in Pharmaceuticals Using a Halogen Moisture Analyzer

How to Calibrate a Moisture Analyzer Video

Moisture Content in Pharmaceuticals Quality Control
Moisture Analyzer Methods for Pharmaceutical Industry
HX204 Moisture Analyzer


1. Can a Halogen Moisture Analyzer replace the drying oven for measurement of moisture content in pharmaceuticals?

Yes, as long as the results obtained by the two methods are comparable. This means that it is necessary to show evidence that the results are equivalent within specific tolerances. A measurement method tailored to the sample is critical. Changing from a drying oven to a halogen moisture analyzer can significantly speed up and simplify the process of moisture analysis in pharmaceuticals.


2. Do USP and EP allow the use of a moisture analyzer for the measurement of moisture content in pharmaceuticals? Under which conditions?

Both USP and EP allow alternative methods to the drying oven for moisture analysis (see USP ch. 6 "General Notes", USP ch. 1010 and EP 2.2.32), as long as the results do not differ by an amount deemed important (USP) and the alternative method, in this case the moisture analyzer, is deemed fit for purpose. In practice, this means that the user has to show that the results are comparable within certain tolerances, and that the moisture analyzer delivers repeatable and dependable results.


3. How do I develop a method to measure moisture in pharma excipients, and why is it important?

A moisture method describes the settings used on a moisture analyzer for analyzing a specific substance. The moisture method used is important in order to obtain results that are comparable with the reference method (typically the drying oven). If there is no reference method, then the aim is to have good repeatability.

METTLER TOLEDO has developed methods for a wide range of pharmaceutical excipients that are available as a method collection. The parameters for each method are an excellent starting point to fine-tune the method to achieve results that accurately and consistently match those from the drying oven process.