Ultra-Fast Analysis of Nitrosamines Using SPE-QQQ

Importance of the Topic

Rapid and reliable quantitation of nitrosamine impurities is critical in pharmaceutical quality control due to the potential carcinogenicity of these compounds. High-throughput screening reduces analytical bottlenecks in regulated and industrial laboratories and ensures product safety while controlling costs.

Objectives and Study Overview

This work aimed to reproduce a US FDA RapidFire SPE-QQQ method for nitrosamine analysis and to evaluate the feasibility of expanding the analyte panel to include additional nitrosamines. The study focused on achieving sub-15-second injection cycles without sacrificing precision or linearity.

Methodology

The workflow combined online solid phase extraction (SPE) with triple quadrupole mass spectrometry (QQQ MS). Key steps included:

• Automated trap, wash and elution cycle optimized for a total analysis time of under 15 seconds per injection
• Graphitic carbon SPE cartridge to remove salts and large matrix components
• Use of aqueous (0.1% formic acid in water) and organic (0.1% formic acid in methanol) buffers for sample loading, washing and elution
• Calibration curves established from low ng/mL to 100 ng/mL to assess linearity and sensitivity

Used Instrumentation

• Agilent RapidFire 400 high-throughput mass spectrometry system
• Agilent Ultivo triple quadrupole LC/MS
• Graphitic carbon SPE cartridges (Type D G9206A)

Main Results and Discussion

An injection rate of approximately 12.5 seconds per sample was achieved, enabling 72 analyses in under 15 minutes with intermittent blank injections to monitor carryover. Precision was demonstrated by coefficients of variation between 4.5% and 9.0% across triplicate injections. Calibration curves for four target nitrosamines showed excellent linearity (R2 values from 0.997 to 0.999) over the tested concentration ranges. Blank runs confirmed minimal carryover, supporting robust routine operation.

Benefits and Practical Applications

• High throughput: sub-15-second cycle times reduce backlog in screening laboratories
• Reproducibility and accuracy comparable to conventional LC-MS methods
• Flexible panel expansion: additional nitrosamines integrated without major method changes
• Efficient matrix removal via SPE improves overall analytical fidelity

Future Trends and Opportunities

The approach can be extended to other trace-level impurities and drug matrices. Potential developments include automated data processing, integration with laboratory information management systems (LIMS), and coupling with high-resolution MS for broader screening. Continued instrument miniaturization and AI-driven method optimization may further enhance throughput and ease of use.

Conclusion

The SPE-QQQ method replicates the FDA rapid nitrosamine screening approach while delivering consistent precision, high linearity and sub-15-second analysis times. Its modular design supports straightforward expansion of analyte panels, making it a powerful tool for routine, high-throughput impurity monitoring.

References

• FDA Updates and Press Announcements on Angiotensin II Receptor Blocker (ARB) Recalls
• Development and Validation of a RapidFire-MS/MS Method for Screening of Nitrosamine Carcinogen Impurities in ARB Drugs
• Information about Nitrosamine Impurities in Medications