Fast, Quantitative SPE LC-MS/MS Analysis of Montelukast in Human Plasma

Significance of the Topic

Montelukast, a leukotriene receptor antagonist used in asthma maintenance therapy, requires sensitive and rapid bioanalytical methods to support pharmacokinetic and clinical research. High-throughput laboratories benefit from workflows that offer speed, reproducibility, and low solvent consumption.

Objectives and Study Overview

This study demonstrates a fast and quantitative method for extracting and analyzing montelukast in human plasma. The approach utilizes a Thermo Scientific SOLA SAX SPE 96-well plate for sample cleanup and an Accucore C8 UHPLC column coupled to a TSQ Vantage mass spectrometer, achieving analysis times under 1.5 minutes and a linear range from 1 to 1000 ng/mL.

Methodology and Instrumentation

Sample preparation begins with protein precipitation in methanol, followed by SOLA SAX solid phase extraction to remove matrix interferences. Eluates are diluted and sonicated prior to analysis.

Instrumentation:

• SPE: Thermo Scientific SOLA SAX 10 mg 96-well plate
• HPLC: Thermo Scientific Dionex UltiMate 3000 RSLC with Accucore C8 (50 × 2.1 mm) column and guard
• MS: Thermo Scientific TSQ Vantage triple quadrupole with heated electrospray ionization (HESI)
• Software: Thermo Scientific LCQUAN version 2.6

Main Results and Discussion

The method delivers a calibration curve with R2 = 0.9901 over 1–1000 ng/mL and a limit of quantitation of 1 ng/mL. Intra-batch precision (RSD) ranged from 2.5% to 10.6% across QC levels (30, 300, 600 ng/mL). Extraction recoveries averaged 89% (84–93%). Chromatography efficiently resolves montelukast isomers and the deuterated internal standard in under 1.5 minutes.

Benefits and Practical Applications

• High-throughput analysis with run times under 1.5 minutes
• Excellent accuracy, precision, and recovery
• Low solvent and elution volume requirements
• Robust performance suitable for pharmacokinetic and clinical studies

Future Trends and Opportunities

Advances may include automation of SPE workflows, integration with ultrahigh-pressure LC for even faster separations, expansion to related leukotriene inhibitors, and enhanced data processing tools for pharmacokinetic modeling.

Conclusion

The combination of SOLA SAX SPE technology and Accucore C8 UHPLC-MS/MS provides a rapid, sensitive, and reliable method for montelukast quantification in human plasma, addressing the needs of modern bioanalytical laboratories.

Reference

• Merck Sharp & Dohme Corp. Singulair (montelukast) Product Monograph. 2012.
• U.S. National Library of Medicine. DailyMed: Montelukast Information. 2012.
• Wikipedia. Montelukast Skeletal Structure. 2012.
• Wishart DS. DrugBank Online. DB00471: Montelukast. Updated 2012.