Development of a High Sensitivity, Sub-Picogram SPE LC-MS Method for Quantification of Mometasone from Human Plasma

Significance of the Topic

Precise quantification of inhaled corticosteroids such as mometasone furoate at sub-picogram levels in human plasma is critical to pharmacokinetic profiling and therapeutic monitoring. The low bioavailability and minimal circulating concentrations challenge conventional analytical methods.

Objectives and Study Overview

This study aimed to develop and validate a highly sensitive, selective, and robust solid-phase extraction (SPE) LC-MS/MS method capable of quantifying mometasone furoate from human plasma down to 0.5 pg/mL.

Methodology and Used Instrumentation

Sample preparation involved spiking 600 µL of human plasma with mometasone furoate and an internal standard (mometasone-d3), followed by SPE using Oasis HLB 1 cc cartridges. The extract was dried and reconstituted for analysis.

• Chromatography: ACQUITY UPLC I-Class FTN system with an ACQUITY BEH Phenyl 1.7 µm, 2.1×100 mm column operated at 50 °C. Gradient elution with 0.1 % formic acid in water (5 mM ammonium formate) and methanol at 0.4 mL/min.
• Mass spectrometry: Xevo TQ-XS triple quadrupole with UniSpray ionization in positive mode. Key MRM transitions: m/z 521.16→355.05 for mometasone furoate and 524.08→355.05 for the deuterated ISTD.
• Data processing: MassLynx for acquisition and TargetLynx for quantification.

Main Results and Discussion

• Extraction recovery of mometasone furoate was approximately 85 %.
• The method achieved a lower limit of quantitation (LLOQ) of 0.5 pg/mL with a signal-to-noise ratio of 19.7.
• Calibration curves were linear over 0.5–60 pg/mL (r2>0.9959) with accuracies within 85–115 % and precision (CV) <15 %.
• Quality control samples at multiple levels demonstrated consistent accuracy and precision, meeting bioanalytical guidelines.

Benefits and Practical Applications

• Supports pharmacokinetic and bioequivalence studies by enabling reliable measurement of low-dose inhaled corticosteroids.
• Enhances throughput and reproducibility using automated SPE and UPLC separation.
• Provides a fit-for-purpose assay for drug discovery, clinical research, and therapeutic monitoring.

Future Trends and Potential Applications

• Integration of microflow LC and high-resolution mass spectrometry to further improve sensitivity and specificity.
• Expansion to multiplexed bioanalysis for simultaneous quantification of multiple inhaled therapies.
• Advancements in SPE sorbent chemistry and ionization techniques to reduce sample volume and processing time.

Conclusion

The described SPE LC-MS/MS method combines targeted sample preparation, high-resolution UPLC separation, and UniSpray MS detection to deliver robust quantification of mometasone furoate at sub-picogram levels, fulfilling stringent bioanalytical requirements for low-level corticosteroid measurement.

References

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4. Srinivasarao et al. Validated Method Development for Estimation of Formoterol Fumarate and Mometasone Furoate in Metered Dose Inhalation Form by HPLC.