Seamless transfer of a compendial LC method for impurity analysis of chlorhexidine from an UltiMate 3000 Standard HPLC system to a Vanquish Core HPLC system

Significance of the topic

Seamless transfer of validated HPLC methods across different instrument platforms ensures consistent impurity profiling, regulatory compliance, and efficient workload distribution in pharmaceutical analysis. The impurity assessment of chlorhexidine—an essential antiseptic listed in pharmacopoeias—exemplifies the need for robust method transfer.

Objectives and overview of the study

• Demonstrate the direct transfer of the European Pharmacopoeia monograph HPLC method for chlorhexidine impurity analysis from a Thermo Scientific UltiMate 3000 Standard HPLC system to a Thermo Scientific Vanquish Core HPLC system.
• Compare chromatographic performance metrics, including resolution, retention time stability, and precision of peak area measurements, between the two systems.

Methodology and instrumentation

The EP monograph method employed a Hypersil GOLD C18 column (4.6 × 250 mm, 5 µm) with mobile phase A (0.1% TFA in water/acetonitrile 80/20 v/v) and mobile phase B (0.1% TFA in water/acetonitrile 10/90 v/v). A linear gradient from 0% to 30% B over 47 min at 1.0 mL/min and column temperature of 30 °C was used. Detection was at 254 nm (4 nm bandwidth), data acquired at 5 Hz.

• UltiMate 3000 SD Quaternary HPLC: SR-3000 solvent rack, LPG-3400SD pump, WPS-3000TSL autosampler, TCC-3000SD column compartment (no pre-heater), DAD-3000 detector (10 mm, 13 µL flow cell).
• Vanquish Core Quaternary HPLC: VC-S01-A-02 system base, VC-P20-A-01 pump, VC-A12-A-02 autosampler, VC-C10-A-03 column compartment with passive pre-heater, VC-D11-A-01 diode array detector (10 mm, 11 µL flow cell).
• Sample: EP reference standard of chlorhexidine digluconate with specified impurities at 5 mg/mL in mobile phase A. Data handled in Chromeleon 7.3 software.

Main results and discussion

Both systems generated highly comparable chromatograms: retention times differed by less than 1.2% and peak areas by under 3%. The Vanquish Core system delivered slightly higher resolution—attributable to its lower dispersion volume—and significantly improved retention time repeatability, with RSD ≤ 0.03% versus up to 0.16% on the UltiMate 3000 SD. Peak area RSD values were below 0.5% on both systems. System suitability criteria (resolution ≥ 3 for impurities L/G and peak-to-valley ≥ 2 for impurity B) were met easily on both instruments.

Benefits and practical applications

• Enables reliable distribution of analytical workloads within and between laboratories without revalidation.
• Maintains pharmacopoeial compliance while improving chromatographic resolution and retention stability.
• Supports high-throughput impurity profiling in quality control environments.

Future trends and applications

Advances in HPLC design—such as integrated pre-heating, reduced system dispersion, and enhanced gradient accuracy—will further streamline method transfers. Adoption of UHPLC and real-time data analytics will enable faster, more sensitive impurity characterization and facilitate remote method deployment across global laboratory networks.

Conclusion

The study successfully demonstrated a seamless transfer of the EP chlorhexidine impurity analysis method between UltiMate 3000 SD and Vanquish Core HPLC systems. Equivalent chromatographic performance was achieved, with the Vanquish Core providing enhanced resolution and superior retention time precision.

References

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