Quantitative Analysis of Mevalonate in Plasma Using LC-MS/MS

Quantitative Analysis of Mevalonate in Plasma Using LC-MS/MS

Význam tématu

Cholesterol biosynthesis is a vital metabolic pathway, with mevalonate serving as the key intermediate. Measuring plasmatic mevalonate provides an indirect assessment of in vivo cholesterol production and supports evaluation of lipid-lowering therapies such as statins in clinical research and quality-control environments.

Cíle a přehled studie

This work aimed to establish a rapid, reliable, and sensitive liquid chromatography–tandem mass spectrometry assay for quantifying mevalonate in human plasma. Emphasis was placed on streamlined sample preparation and a short analysis time compatible with high-throughput pharmacological studies.

Použitá metodika a instrumentace

• Sample preparation: 500 µL plasma spiked with 20 ng mevalonate-D7, acidified to convert mevalonate into its lactone form, followed by solid-phase extraction (SPE). Dried extracts were reconstituted in 0.2% ammonium hydroxide and 10 µL injected.
• Chromatography: Thermo Scientific Surveyor autosampler and pump with BioBasic AX column (150 × 2.1 mm, 5 µm). Gradient elution using 10 mM ammonium formate (pH 8) and acetonitrile at 200 µL/min.
• Mass spectrometry: Thermo LTQ linear ion trap with electrospray ionization in negative mode. Monitored transitions: m/z 147→59 for mevalonate and m/z 154→59 for mevalonate-D7. Key settings: spray voltage 2 kV, sheath/auxiliary gas nitrogen, ion transfer tube at 300 °C, collision energy 30%.

Hlavní výsledky a diskuse

• Linearity: Calibration range 2.5–250 ng/mL with correlation coefficient r2 > 0.9993 (1/x weighting).
• Precision: Intraday coefficient of variation between 0.5% and 4% (n=3).
• Sensitivity: Limit of detection 2 pg; limit of quantification 2.5 ng/mL.
• Run time: Total analysis completed in 10 minutes, analyte elution between 3.0 and 6.5 minutes.
• Validation: Successful quantification of mevalonate in a healthy volunteer sample (24 ng/mL).

Přínosy a praktické využití metody

• High throughput capability suitable for pharmacokinetic and clinical investigations.
• SPE cleanup reduces matrix effects and simplifies sample handling.
• Use of stable isotope internal standard ensures accurate quantification across diverse plasma matrices.

Budoucí trendy a možnosti využití

Future developments may include automated sample preparation workflows, miniaturized LC-MS platforms for bedside monitoring, and expanded multiplex assays profiling additional cholesterol pathway intermediates. Coupling with high-resolution mass spectrometry could further enhance specificity and broaden metabolite coverage.

Závěr

A robust, 10-minute LC-MS/MS method has been validated for sensitive and precise quantification of mevalonate in plasma. This protocol offers a valuable tool for clinical pharmacology and research into cholesterol metabolism.