Fully automated sample preparation for the content determination of tablets

Significance of the Topic

In pharmaceutical quality control, verifying the active ingredient content in each tablet is essential to ensure dosage accuracy and patient safety. Automated sample preparation combined with rapid titrimetric analysis offers a streamlined approach to maintain consistency, boost throughput, and reduce human error.

Objectives and Study Overview

This study aimed to develop a fully automated workflow for determining benzbromaron content in tablets by:

• Automating sample homogenization and dilution steps.
• Integrating titration for quantitation of benzbromaron, a uricosuric drug.
• Comparing single-tablet and multi-tablet analysis for precision and speed.

Methodology and Instrumentation

Samples of one or three benzbromaron tablets were processed in an automated system within 8 minutes total analysis time. Key steps included:

• Automated weighing and identification using tiamo™ software.
• High-frequency homogenization: one tablet in 90 s or three tablets in 120 s with 25 000 rpm Polytron homogenizer in methanol.
• Dilution with water and automated transfer to titration vessel.
• Titration with 1 mol/L NaOH on an 809 Titrando equipped with a Solvotrode; endpoint detection and in-line rinsing completed automatically.

Key Results and Discussion

Ten replicate analyses produced:

• Single-tablet content: mean 99.2 mg, RSD 1.36 % (target approx. 100 mg/tablet).
• Three-tablet content: mean 98.7 mg, RSD 0.88 % (improved precision).

Increasing the batch size to three tablets reduced relative standard deviation, demonstrating enhanced reproducibility. The automated workflow eliminated manual handling variability and delivered results in under 8 minutes per run.

Benefits and Practical Applications

The combined homogenization–titration automation offers multiple advantages:

• High throughput: multiple samples processed sequentially with minimal user intervention.
• Improved reproducibility and accuracy compared to manual methods.
• Enhanced laboratory safety via reduced solvent exposure and handling.
• Flexibility: adaptable to other pharmaceutical compounds and analytical techniques (IC, HPLC, ICP, voltammetry).

Future Trends and Opportunities

Advances in robotic sample processors may enable:

• Integration with chromatography and mass spectrometry workflows for comprehensive multi‐parameter analysis.
• Adaptation to solid‐phase extraction and microfluidic platforms for trace‐level quantitation.
• AI-driven method optimization to further reduce analysis time and reagent consumption.

Conclusion

The fully automated sample preparation and titration method for benzbromaron in tablets offers rapid, accurate, and reproducible content determination. Scaling from one to three tablets improves precision while maintaining short cycle times, making it a valuable tool for routine pharmaceutical quality assurance.