Development and Validation of a Method for Quantification of 28 Psychotropic Drugs in Postmortem Blood Samples by...

Area of Science:

• Analytical Toxicology
• Forensic Chemistry
• Pharmacology

Background:

• Growing need for rapid, automated, and eco-friendly sample preparation in analytical toxicology.
• QuEChERS (Quick, Easy, Cheap, Rugged, and Efficient) offers cleaner extracts and easier phase separation than traditional methods.
• Limited studies exist on miniaturized QuEChERS for forensic toxicology, particularly in postmortem analysis.

Purpose of the Study:

• To develop and validate a modified micro-QuEChERS method coupled with LC-MS-MS for quantifying antidepressants and antipsychotics in postmortem blood.
• To assess the method's efficiency, accuracy, and applicability to real-world forensic samples.

Main Methods:

• Developed a modified micro-QuEChERS procedure using a small blood volume (100 µL).
• Utilized Liquid Chromatography-Tandem Mass Spectrometry (LC-MS-MS) for quantification.
• Validated the assay for linearity, precision, bias, and interferences, analyzing six weighting factors for calibration curves.

Main Results:

• Achieved linear calibration curves (r > 0.99) from 1 to 500 ng/mL for 26 substances.
• Quantification within ±15% of target (±20% at LOQ of 1 ng/mL).
• Demonstrated low method imprecision (<19.0%) and bias (<19.7%), with no observed interferences. Method run time was 8.5 minutes.

Conclusions:

• The developed micro-QuEChERS and LC-MS-MS assay is a robust and efficient method for analyzing antidepressants and antipsychotics in postmortem blood.
• The method's advantages include minimal sample volume, simplified preparation, and rapid analysis.
• Successfully applied to 100 authentic postmortem samples, demonstrating its practical utility in forensic toxicology.