Impurities test for Tranexamic Acid (EP method)

Importance of the Topic

• The control of impurities in pharmaceutical compounds is critical to ensure drug safety and efficacy.
• Tranexamic acid is widely used as an antifibrinolytic agent, making reliable impurity testing essential for quality assurance.

Objectives and Study Overview

• Present a validated European Pharmacopeia (EP) method for identifying and quantifying impurities in tranexamic acid.
• Describe sample preparation, chromatographic conditions, and system suitability criteria.
• Demonstrate method performance through resolution and relative retention time measurements.

Methodology and Instrumentation

• Sample Preparation
  
  • Test solution: 0.2 g tranexamic acid dissolved in water and diluted to 20 mL.
  • Reference solution A: 5 mL test solution diluted to 100 mL, then 1 mL of that to 10 mL.
  • Reference solution B: 20 mg tranexamic acid impurity C in water to 2 mL.
  • Reference solution C: 12 mg impurity D to 100 mL, further dilutions to achieve final volume.
• Chromatographic Conditions
  
  • Instrument: UltiMate 3000 LC.
  • Column: Hypersil GOLD, 4.6×250 mm, 5 μm.
  • Mobile phase: phosphate buffer with triethylamine and sodium lauryl sulfate, pH 2.5, mixed with methanol (60:40).
  • Mode: isocratic, flow rate 0.9 mL/min, column temperature 25 °C.
  • Detection: UV at 220 nm, injection volume 20 μL, run time 40 min.
• System Suitability Criteria
  
  • Resolution between tranexamic acid and impurity C >= 1.5.
  • Relative retention times (RRT) for impurities compared to the main peak.

Main Results and Discussion

• Resolution achieved between tranexamic acid and impurity C was 3.48, exceeding the EP requirement of 1.5.
• Observed RRT values:
  
  • Impurity C: 1.15 (target ~1.1).
  • Impurity D: 1.22 (target ~1.3).
  • Impurity B: 1.54 (target ~1.5).
• Chromatograms confirmed clear separation of all identified impurities within a 40 min runtime.
• Method demonstrates high specificity, suitable for routine quality control.

Benefits and Practical Applications

• Provides a robust assay for impurity profiling in tranexamic acid batches.
• Supports regulatory compliance by meeting EP standards.
• Enables laboratories to reliably monitor critical impurities in production and stability studies.

Future Trends and Applications

• Integration with advanced detectors, such as mass spectrometry, for structural confirmation of unknown impurities.
• Adoption of shorter columns and faster gradients to reduce analysis time.
• Implementation of automated data processing and digital workflows for enhanced throughput.

Conclusion

• The EP method for tranexamic acid impurity testing is validated, specific, and reliable for quality control laboratories.
• System suitability results exceed required criteria, ensuring accurate detection and quantification of related substances.
• The approach supports pharmaceutical manufacturers in maintaining product purity and safety.

References

• No external references cited in this summary.