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Published on: May 8, 2015
Quantitative analysis of diphenhydramine hydrochloride in pharmaceutical wafers using near infrared and Raman
Maren Haag1, Michael Brüning, Karl Molt
1Analytical Development, Bayer Schering Pharma AG, Müllerstrasse 178, 13353 Berlin, Germany. maren.haag@bayerhealthcare.com
Abstract:
Wafers with varying concentrations of diphenhydramine hydrochloride (DPH-HCl) as active pharmaceutical ingredient (API) were prepared and their near infrared (NIR) and Raman spectra recorded. The purpose of this study was to compare the suitability of these two vibrational spectroscopic techniques for the quantification of DPH-HCl in pharmaceutical wafers. Partial least squares (PLS1) calibration models with different data pretreatments were tested. Both NIR and Raman spectroscopy proved to be suitable to predict DPH-HCl contents at lower concentration ranges. At higher concentrations, interference by crystallization processes was observed. For investigating the general applicability of the quantification methods, two commercially available products were examined.
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