Practical Considerations in the Measurement of the Internal Relative Humidity of Pharmaceutical Packages with Data Loggers
- 150 Downloads
The utility of temperature/humidity data loggers are evaluated as a low-cost approach to enrich practical understanding of the actual time dependent humidity that a pharmaceutical product is exposed to. While this approach is found to have significant utility in general, small systematic biases in the measurements due to the presence of the data logger are observed. Taking these biases into account enables more productive extrapolation of measured time/humidity profiles.
KEY WORDSdata logger humidity moisture stability water activity
Dr. Rajiv Mahajan and Dr. Rey Chern are thanked for many hours of helpful discussion of the underlying technical significance of water activity and packaging science. Prof. Carl Nelson is thanked for thoughtful feedback and input into the theoretical background discussed in this manuscript.
- 3.Chern RT, Mahajan R, Juang RH, Forster R. Prediction of water activity in primary packages for pharmaceutical solids. Polym Prepr. 2004;45:3–4.Google Scholar
- 4.Chern RT, Mahajan R, Juang RH, Forster R. Prediction of water activity in primary packages for pharmaceutical solids. PMSE Prepr. 2003;89:25–6.Google Scholar
- 6.Barry J, Bergum J, Chen Y, Chern R, Hollander R, Klein D, et al. Basis for using moisture vapor transmission rate per unit product in the evaluation of moisture-barrier equivalence of primary packages for solid oral dosage forms. Pharmacopeial Forum. 2005;31(1):262–9.Google Scholar
- 7.For other examples see: Y. Li, Y. D. Sanzgiri, and Y. Chen, A Study on Moisture Isotherms of Formulations: the Use of Polynomial Equations to Predict the Moisture Isotherms of Tablet Products, AAPS PharmSciTech 2006;4(4). Article 59 (http://www.aapspharmscitech.org).