Portable Transmission Raman Spectroscopy for At-Line Content Uniformity Testing of Pharmaceutical Tablets

Význam tématu

Content uniformity testing is a critical quality requirement in pharmaceutical production to verify that each tablet contains the correct dose of active pharmaceutical ingredient. Traditional high performance liquid chromatography methods are sensitive but time-consuming, destructive, and resource-intensive. Fast, noninvasive strategies that require minimal sample preparation can improve manufacturing throughput and reduce delays.

Cíle a přehled studie / článku

This article evaluates a portable transmission Raman spectroscopy system for at-line content uniformity analysis of tablets containing acetaminophen and lactose. A proof-of-concept study demonstrates method development, validation, and prediction workflows using chemometric models to quantify tablet composition rapidly and nondestructively.

Použitá metodika a instrumentace

The following instrumentation and workflow were employed:

• QTRam portable Raman spectrometer equipped with a 785 nm laser (max 340 mW) and ~4 mm spot size
• Transmission Raman optics (STRaman technology) to illuminate one tablet side and collect signal from the opposite side
• BWAnalyst software for data acquisition, method construction, and compliance reporting
• BWIQ chemometric software for model building (adaptive iteratively reweighted penalized least squares background correction, multiplicative scatter correction, Savitzky-Golay first derivative, partial least squares regression)
• Gamlen tablet press to compress blends into 6 mm diameter, 4.5 mm thick tablets (~140 mg each)

The study prepared five blends with acetaminophen content ranging from 10 to 18% w/w and lactose content from 10.8 to 28.7% w/w. Ten tablets per blend were measured on both sides with 20 second integration at full laser power.

Hlavní výsledky a diskuse

Chemometric models were built using spectra from seven tablets per blend (105 spectra). Key spectral regions for acetaminophen (1190–1300 and 1530–1700 cm–1) and lactose (285–500 and 840–890 cm–1) were selected. Preprocessing removed background variability and corrected scattering effects. Partial least squares regression yielded high calibration performance (R2 > 0.99) and low root mean square error (RMSE of 0.23% w/w for acetaminophen, 0.53% w/w for lactose).

Validation on independent tablets produced standard deviations below 0.2% w/w for acetaminophen and below 0.4% w/w for lactose. Method acceptance criteria (acetaminophen 10–14% w/w, lactose 18–30% w/w) resulted in clear pass/fail calls using BWAnalyst. Prediction of new samples demonstrated agreement within acceptance limits for one blend and appropriate fail outcomes for others.

Přínosy a praktické využití metody

• Rapid at-line results in less than one minute per tablet
• Non-destructive analysis with no solvent or consumables requirement
• Full-volume sampling that penetrates tablet coatings
• Simple pass/fail workflow suitable for routine quality control
• Flexibility to assess blend uniformity and detect counterfeit formulations

Budoucí trendy a možnosti využití

Ongoing advances in portable Raman instrumentation and chemometric algorithms may extend this approach to multicomponent formulations with lower API loads. Integration with manufacturing execution systems can enable real-time process monitoring. Future work may focus on automated sampling accessories, expanded spectral libraries, and machine learning models for enhanced robustness under varying environmental conditions.

Závěr

This study establishes portable transmission Raman spectroscopy combined with chemometric modeling as a viable at-line tool for rapid, accurate, noninvasive content uniformity testing of pharmaceutical tablets. The approach eliminates solvent use, reduces analysis time, and delivers representative full-volume measurements suitable for quality assurance in production environments.

Reference

• No external references were provided in the original document