LC-MS/MS Method for the Determination of Paclitaxel in Human Serum

Importance of the Topic

Quantification of paclitaxel in human serum is critical for therapeutic drug monitoring, pharmacokinetic profiling and ensuring effective and safe dosing in oncology patients.

Objectives and Study Overview

This work describes the development of a rapid, sensitive and reproducible LC-MS/MS method for paclitaxel analysis in human serum. The method combines Thermo Scientific SOLA solid-phase extraction (SPE) with Accucore RP-MS core–shell chromatography to achieve a 2-minute cycle time.

Methodology

• Sample Pretreatment: Blank human serum (200 µL) spiked with paclitaxel standard and docetaxel internal standard, vortexed and centrifuged.
• SPE Cleanup: Thermo Scientific SOLA 10 mg/2 mL cartridges conditioned with methanol and water, sample applied at ~1 mL/min, washed with 70:30 water/acetonitrile, eluted with acetonitrile + 1% ammonia, dried under nitrogen, reconstituted in 50:50 water/acetonitrile with sodium acetate.
• Chromatographic Separation: Thermo Scientific Dionex UltiMate 3000 RSLC system with Accucore RP-MS 2.6 µm, 50×2.1 mm column; gradient 60–70% methanol (0.1% formic acid) over 2 min, flow rate 0.6 mL/min, column temp 30 °C, injection volume 2.5 µL.
• Mass Spectrometry: Thermo Scientific TSQ Vantage with HESI in positive mode; transitions m/z 876.3→308.3 for paclitaxel and m/z 830.3→549.2 for docetaxel, optimized collision energy and S-lens voltages.
• Data Processing: Thermo Scientific LC QUAN software for quantification.

Used Instrumentation

• Thermo Scientific SOLA SPE cartridges (10 mg/2 mL)
• Thermo Scientific Dionex UltiMate 3000 RSLC HPLC system
• Accucore RP-MS 2.6 µm, 50×2.1 mm column
• Thermo Scientific TSQ Vantage mass spectrometer

Main Results and Discussion

• Excellent linearity from 0.1 to 10 ng/mL (r²=0.9982).
• LLOQ achieved at 0.1 ng/mL with clear chromatographic peak shape.
• Precision at QC levels (0.3, 1.5, 6 ng/mL) was ≤6.6% CV.
• Extraction recovery determined at 116% using post-extraction overspikes.

Benefits and Practical Applications

This method delivers high throughput analysis with minimal solvent consumption, robust recoveries and reproducible results, making it suitable for clinical bioanalysis, pharmacokinetic studies and quality control workflows.

Future Trends and Potential Applications

Emerging core–shell column technologies and SPE sorbents may further reduce analysis times and improve sensitivity. Automation and multiplexed assays could broaden applications in personalized medicine and high-throughput screening.

Conclusion

The combined SOLA SPE and Accucore RP-MS LC-MS/MS approach provides a fast, sensitive and reliable method for paclitaxel quantitation in human serum, demonstrating strong linearity, precision and recovery.

References

• Jones J, Denbigh J. LC-MS/MS Method for the Determination of Paclitaxel in Human Serum. Thermo Fisher Scientific Application Note 20704; 2013.