Content uniformity (CU) is a key analytical parameter in pharmaceutical testing, particularly in quality control of dosage form tablets. The U.S. Food and Drug Administration (FDA) upholds content uniformity testing as an “important assessment of unit dosage form performance”. This extends to both official and non-official United States Pharmacopeia (USP) products; non-official goods are also required to meet regulatory standards with respect to their as-marketed potency and quality. Furthermore, it is not enough to rely on clinical responses as an indicator of content uniformity performance, given the complex nature of pharmacological responses.
Raman spectroscopy can meet the needs of unit dosage content uniformity testing in-line with current good manufacturing practice (cGMP). It is one of the few technologies capable of non-destructively assaying tablet content to measure uniformity; others include near-infrared (NIR) spectroscopy and weight variation (WV) testing. In this post, B&W Tek explores the use of Raman spectroscopy in content uniformity testing in greater depth.
Outlining Content Uniformity
The USP defines content uniformity as the degree of uniformity in the amount of the drug substance among dosage units. It essentially tests whether the concentration of the active pharmaceutical ingredient (API) in the dosage form product falls within acceptable limits for consumer safety. Deviation from the average concentration range in more than one unit in a sample may result in non-compliance. Raman spectroscopy provides rapid, quantitative content uniformity testing to ensure that API concentration is consistent with the intended level to meet both market and regulatory quality standards.
Testing Tablets with Raman Spectroscopy
The immediate benefit of using Raman spectroscopy for content uniformity testing is the non-destructive nature of the technology. Tablets are not consumed during mandatory quality-control tests, limiting the cost burden of USP compliance with respect to uniformity of dosage units.
Using laser light as an excitation source, Raman spectrometers measure the light scattered from a sample to determine its chemical composition at the atomic scale. By using transmission Raman, the measurement transverses the sample volume, as opposed to measuring just the surface, which is not representative of the assay in the solid dosage unit. This spectral fingerprint is used to determine tablet content and API concentration relative to an acceptable margin of uniformity. Solid dosage content uniformity testing with transmission Raman spectroscopy can even quantify sample composition and API concentration through tablet coatings.
B&W Tek: Raman Spectroscopy Solutions
B&W Tek is one of the industry-leading suppliers of quality control solutions for pharmaceutical manufacturers. We have powered our portable QTRam spectrometer with our patented ST Raman technology in a transmission, for rapid, quantitative analysis of solid dosages in blend and content uniformity applications. This compact one-system tool can quantify several constituents in just one scan for at-line screening and quality control testing of solid dose pharmaceuticals.