Non-destructive analysis of drug content in polymer coatings with Raman spectroscopy : Current Directions in Biomedical Engineering

摘要

The analysis of device drug content typically is carried out by means of chromatographic methods such as high performance liquid chromatography (HPLC) or liquid chromatography-mass spectrometry (LCMS). These approved methods are particularly fast, cost-efficient and ubiquitous in chemical-analytical laboratories. However, these quantitative methods necessitate the drug being eluted, which represents a destructive process. A novel alternative to these well-established methods [1, 2] is the Raman spectroscopy, which is fast and cost-efficient, as well [3]. Additionally, it offers the advantage of nondestructive analysis without the need for a special sample preparation. Within the current investigation we applied Raman spectroscopy for the qualitative and quantitative analysis of dexamethasone (DMS), a glucocorticoid, incorporated in a silicone matrix. The investigation was conducted in a rectangular area on the sample surface. The required number of measuring points (spectra) was determined. Calibration was performed with samples containing different amounts of DMS. The evaluation of Raman spectra is based on the analysis of the peak areas of the bands at 795 rel. cm-1(silicone) and 1,663 rel. cm-1(DMS). Remarkably, next to a precise overview of DMS distribution, an exact and reproducible quantification of incorporated DMS could be obtained.