Demonstration of the USP Quetiapine Fumarate Impurities Method Across a Wide Range of Liquid Chromatographic Systems

Significance of the Topic

The control of impurities in quetiapine fumarate formulations is essential to ensure patient safety and product quality. The United States Pharmacopeia (USP) method provides critical guidelines for the detection and quantification of related substances. Demonstrating the method across different liquid chromatography platforms highlights its versatility and confirms compliance with regulatory standards in pharmaceutical testing.

Objectives and Study Overview

This application note evaluates the USP quetiapine fumarate impurity method on three chromatography systems: Alliance HPLC, ACQUITY Arc UHPLC, and ACQUITY UPLC H-Class PLUS. Key goals include verifying system suitability, comparing chromatographic performance, and quantifying impurities in an unknown sample.

Methodology and Instrumentation

Sample Preparation:

• System suitability, standard, and identification solutions prepared per USP monograph in acetonitrile/buffer diluent.
• Concentrations: 1.0 mg/mL (system suitability and sample), 0.001 mg/mL (standard), and specific µg/mL levels for impurity identification.

Chromatographic Conditions:

• Column: XBridge BEH C8, 3.5 µm, 4.6×150 mm.
• Gradient: 0–25 min at 100% A (acetonitrile/buffer), 25–60 min to 70.7% B (acetonitrile), return to initial by 68 min.
• Flow rate: 1.5 mL/min; column temp: 45 °C; detection: PDA at 250 nm.

Instrumentation:

• Alliance e2695 HPLC with 2998 PDA detector.
• ACQUITY Arc UHPLC with active solvent preheating and 2998 PDA.
• ACQUITY UPLC H-Class PLUS with 50 µL loop and UPLC PDA detector.
• Data acquisition: Empower 3 software.

Main Results and Discussion

System Suitability:

• Resolution between critical pairs met USP criteria (desethoxy vs. quetiapine ≥6.6; compound B vs. G ≥11.0) on all systems.
• Dispersion values decreased from 44.5 µL (HPLC) to 9.6 µL (UPLC), yielding narrower peaks and 2–3× higher peak heights.

Peak Shape and Precision:

• Tailing factors ≤1.1 and %RSDs for retention time and area below 1.2% on all platforms, satisfying USP limits.

Impurity Quantification:

• Quetiapine desethoxy and an unknown impurity were detected in the sample at 0.10–0.13% and 0.07–0.08% respectively, all below USP thresholds.
• Results were consistent across HPLC, UHPLC, and UPLC systems.

Benefits and Practical Applications

The ability to implement the USP method on varied chromatographic platforms provides laboratories with flexibility in instrument selection. Lower dispersion systems (UHPLC/UPLC) enhance sensitivity and throughput without compromising method compliance. This fosters efficient impurity profiling in quality control and R&D settings.

Future Trends and Opportunities

• Integration with high-resolution mass spectrometry for structural confirmation.
• Adoption of shorter columns and faster gradients to further reduce run times.
• Implementation of greener solvents and automation to improve sustainability and reproducibility.

Conclusion

The USP quetiapine fumarate impurity method successfully transfers across HPLC, UHPLC, and UPLC platforms, meeting all system suitability and impurity acceptance criteria. Consistent quantification and enhanced sensitivity on lower dispersion systems support robust impurity analysis in pharmaceutical laboratories.

References

1. USP 40–NF35 S1 Monograph, Quetiapine Fumarate, United States Pharmacopeia and National Formulary, 2017.
2. Hong P., McConville P. ‘‘Dwell Volume and Extra-Column Volume: What Are They and How Do They Impact Method Transfer,’’ Waters White Paper 720005723EN, 2016.
3. Snyder L.R., Kirkland J., Dolan J.W. Introduction to Liquid Chromatography, 3rd Edition, Wiley, 2010.
4. USP <621> Chromatography, United States Pharmacopeia and National Formulary, 2017.