Ultrafast Analysis of Selective Serotonin Reuptake Inhibitors (SSRIs) in Human Serum by the Agilent RapidFire High-Throughput Triple Quadrupole Mass Spectrometry System

Význam tématu

Selective serotonin reuptake inhibitors (SSRIs) are among the most commonly prescribed psychotropic medications. Accurate quantification of these drugs in human serum supports therapeutic drug monitoring, pharmacokinetic studies, and drug–drug interaction assessments. Traditional liquid chromatography–mass spectrometry (LC–MS/MS) methods can be time-consuming and limit throughput in clinical research and high-volume laboratories.

Cíle a přehled studie / článku

This application note describes the development and validation of an ultrafast method for simultaneous quantification of six SSRIs (citalopram, N-desmethyl citalopram, fluoxetine, norfluoxetine, sertraline, paroxetine) in human serum. The method employs an Agilent RapidFire High-Throughput SPE coupled with a 6490 Triple Quadrupole Mass Spectrometer to achieve sample cycle times of 13 seconds and throughputs exceeding 250 samples per hour.

Použitá metodika a instrumentace

Samples underwent protein crash with zinc sulfate and acetonitrile containing an internal standard (citalopram-d6), followed by 1:10 dilution in 0.1% formic acid. Automated solid-phase extraction was performed on an Agilent RapidFire C18 cartridge.

• Injection volume: 10 µL
• Buffers: water + 0.1% formic acid (Pump 1, 1.5 mL/min); acetonitrile + 0.1% formic acid (Pumps 2 & 3, 1.25 mL/min)
• SPE cycle times (four RF states between 500–7,000 ms)

Použitá instrumentace

• Agilent RapidFire 360 High Throughput Mass Spectrometry System
• Agilent 6490 Triple Quadrupole Mass Spectrometer
• Agilent MassHunter Qualitative Analysis B.05.00
• Agilent MassHunter Quantitative Analysis B.05.00

Hlavní výsledky a diskuse

The method displayed linear calibration curves for all six SSRIs over 10–500 ng/mL with R2 values >0.99. Limits of detection were below 5 ng/mL. Intra- and interday accuracy remained within ±10% and precision (CV) within 10% across all concentrations. Representative data showed no significant carryover when injecting a blank after the highest calibrator. The system achieved a consistent 13-second cycle per sample, equivalent to >250 injections per hour, representing a >10-fold increase in throughput compared to conventional LC–MS/MS.

Přínosy a praktické využití metody

This ultrafast SPE/MS/MS approach offers:

• High throughput compatible with large clinical cohorts or high-volume QC laboratories
• Robust quantification with validated accuracy and precision
• Minimal carryover and simplified sample preparation
• Direct integration into existing MassHunter data workflows

Budoucí trendy a možnosti využití

Future developments may include expanding the analyte panel to additional antidepressants or metabolites, incorporating automated sample handling for fully walk-away operation, and coupling with data analytics or machine-learning tools for real-time quality control. The RapidFire platform could also be adapted for other high-value therapeutic or toxicology applications.

Závěr

The Agilent RapidFire High-Throughput SPE coupled with a 6490 Triple Quadrupole MS enables ultrafast, accurate, and precise quantification of SSRIs in human serum. With sample cycle times of 13 seconds and throughput exceeding 250 samples per hour, this methodology significantly accelerates routine and research applications compared to traditional LC–MS/MS methods.

Reference

1. Barlow, D. H.; Durand, V. M. Mood Disorders and Suicide. In Abnormal Psychology: An Integrative Approach; Wadsworth Cengage Learning, 2009, p 239.
2. Preskorn, S. H.; Ross, R.; Stanga, C. Y. Selective Serotonin Reuptake Inhibitors. In Antidepressants: Past, Present and Future; Springer, 2004, pp 241–262.