Quantification of Drugs in Brain Samples.

Area of Science:

• Forensic Toxicology
• Analytical Chemistry
• Biochemistry

Background:

• Reliable quantification in complex postmortem matrices is challenging due to the lack of certified reference materials.
• Standard addition methods are viable but require highly reproducible extraction procedures.
• Automated solid-phase extraction (SPE) offers a potential solution for consistent sample preparation.

Purpose of the Study:

• To validate an automated solid-phase extraction (SPE) screening procedure for postmortem analyses.
• To assess the method's suitability for standard addition quantification in complex matrices.
• To evaluate the impact of initial concentration estimates on calibration curve accuracy.

Main Methods:

• Validation of an automated SPE method using fortified pig brain samples.
• Inclusion of nine representative compounds to simulate realistic postmortem conditions.
• Assessment of validation parameters: linearity, repeatability, reproducibility, and recovery.

Main Results:

• The automated SPE method demonstrated satisfactory performance across all tested validation parameters.
• The method proved suitable for standard addition experiments, despite not being optimized for the specific compounds.
• Accurate concentration estimation is critical for calibration curve reliability; underestimation is preferable to overestimation.

Conclusions:

• A validated automated SPE method can be effectively employed for standard addition quantification in postmortem samples.
• The accuracy of the initial concentration estimate significantly influences the reliability of the final quantification.
• This validated method facilitates further research into optimizing standard addition protocols in forensic analysis.