Expanding fentanyl analog testing to include brain specimens: method validation and homogenate stability assessment

Area of Science:

• Forensic Toxicology
• Analytical Chemistry
• Neuroscience

Background:

• Fentanyl analogs are potent synthetic opioids with significant public health implications.
• Limited research exists on detecting fentanyl analogs in brain tissue.
• Brain tissue offers unique advantages for drug analysis due to lower metabolic activity.

Purpose of the Study:

• To develop and validate a method for testing fentanyl analogs in brain tissue.
• To assess the stability of fentanyl analogs in brain homogenates under various storage conditions.
• To contribute data to the limited literature on brain toxicology for fentanyl analogs.

Main Methods:

• Developed and validated a solid phase extraction and liquid chromatography-tandem mass spectrometry (LC-MS/MS) method.
• Assessed method performance including LOD, LOQ, calibration, bias, precision, and interferences.
• Investigated brain homogenate stability over 90 days at different temperatures (room temp, refrigerated, frozen) and freeze-thaw cycles.

Main Results:

• The LC-MS/MS method successfully quantified fentanyl analogs in brain tissue.
• Carfentanil, fentanyl, furanyl fentanyl, and methoxyacetyl fentanyl met quantitative criteria.
• Frozen brain homogenates remained stable for 90 days and withstood three freeze-thaw cycles for several analogs, with 1% sodium fluoride showing no adverse impact.

Conclusions:

• The developed method is feasible for testing fentanyl analogs in brain samples.
• Frozen storage up to 90 days is suitable for preserving fentanyl analogs in brain homogenates.
• This study provides crucial data on fentanyl analog stability in brain tissue for forensic applications.