Author(s)

Paul Matejtschuk¹, Chinwe Duru¹, Kiran Malik¹, Ernest Ezeajughi¹, Elaine Gray², Sanj Raut², Fatme Mawas³

¹Standardization Science, National Institute for Biological Standards & Control (NIBSC), Hertfordshire, UK.
²Biotherapeutics Division, National Institute for Biological Standards & Control (NIBSC), Hertfordshire, UK.
³Bacteriology Division, National Institute for Biological Standards & Control (NIBSC), Hertfordshire, UK.

Residual moisture is a key quality control parameter for lyophilized biologicals, as high moisture can correlate with poor stability. Coulometric Karl Fischer titration is the most widely used technology to determine residual water content; some chemicals are known to cause problems with Karl Fischer titration, but these chemicals do not usually occur in biologics. Three biological samples, of fibrinogen, heparin and Haemophilus influenza b polysaccharide, have caused particular issue in our hands by routine Karl Fischer analysis, illustrating different limitations with this method. The use of thermogravimetric analysis, with evolved gas mass spectrometric monitoring, is described here as a successful alternative for moisture analysis in these materials.

Thermogravimetric Analysis, Freeze Dried, Moisture Determination, Karl Fischer Titration

Matejtschuk, P. , Duru, C. , Malik, K. , Ezeajughi, E. , Gray, E. , Raut, S. and Mawas, F. (2016) Use of Thermogravimetric Analysis for Moisture Determination in Difficult Lyophilized Biological Samples. American Journal of Analytical Chemistry, 7, 260-265. doi: 10.4236/ajac.2016.73023.