Impurities test for Mefenamic Acid (EP- method)

Significance of the Topic

The reliable detection of impurities in Mefenamic acid is critical to ensure product safety and compliance with pharmacopeial standards. This method addresses the need for precise identification and quantification of trace-level contaminants in pharmaceutical quality control.

Objectives and Overview of the Study

The objective of this study is to implement the European Pharmacopoeia (EP) method for impurity profiling of Mefenamic acid. The approach involves preparing test and reference solutions, optimizing chromatographic separation, and validating system suitability parameters to meet regulatory criteria.

Methodology

• Sample Preparation: Description of test and four reference solutions, including dilution schemes for impurities A, C, and D.
• Chromatographic Conditions: Isocratic separation on a Hypersil Gold column (4.6×250 mm, 5 µm) at 25 °C, using a mobile phase composed of tetrahydrofuran, phosphate buffer (pH 5.0) and acetonitrile. Flow rate 1.0 mL/min; injection volume 10 µL; UV detection at 254 nm; run time 35 min.

Used Instrumentation

• HPLC System: UltiMate 3000 LC.
• Column: Hypersil Gold (p/n 25005-254630).

Main Results and Discussion

System suitability data demonstrated robust performance: resolution between impurities C and D exceeded the EP requirement (4.5 vs. 3.0), and the retention time of Mefenamic acid was consistent (8.155 min). Relative retention times for impurities A, C and D were within expected ranges, confirming effective separation and method specificity.

Benefits and Practical Applications

• The method offers high resolution of critical impurities under isocratic conditions, facilitating routine quality control in pharmaceutical laboratories.
• It ensures compliance with European Pharmacopoeia standards, supporting regulatory approval.
• Simplicity of sample preparation and stable chromatographic conditions enhance reproducibility and throughput.

Future Trends and Potential Applications

Advancements may include integration with UHPLC for reduced run times, coupling to mass spectrometry for improved sensitivity, adoption of greener solvents to comply with sustainability goals, and automation of sample preparation to increase laboratory efficiency.

Conclusion

The EP method for impurity testing of Mefenamic acid is validated as a reliable, specific, and reproducible approach for detecting impurities at trace levels. It fulfills pharmacopeial requirements and supports quality assurance in pharmaceutical production.