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Data-Independent Screening Method for 14 Fentanyl Analogs in Whole Blood and Oral Fluid Using LC-QTOF-MS

NCJ Number
Forensic Science International Volume: 297 Dated: April 2019 Pages: 189-197
Date Published
April 2019
9 pages

This project developed and validated a data-independent screening method for 14 fentanyl analogs in whole blood and oral fluid, using liquid chromatography-quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS).


Recently, fentanyl analogs have accounted for a significant number of opioid deaths in the United States. Routine forensic analyses are often unable to detect and differentiate these analogs due to low concentrations and presence of structural isomers. In the current project, data were acquired using Time of Flight (TOF) and All Ions Fragmentation (AIF) modes. The limits of detection (LOD) in blood were 0.1-1.0ng/mL and 0.1-1.0ng/mL in TOF and AIF modes, respectively. In oral fluid, the LODs were 0.25ng/mL and 0.25-2.5ng/mL in TOF and AIF modes, respectively. Matrix effects in blood were acceptable for most analytes (1-14.4 percent), while the nor-metabolites exhibited ion suppression >25 percent. Matrix effects in oral fluid were 11.7 to 13.3 percent. Stability was assessed after 24h in the autosampler (4 degrees C) and refrigerator (4 degrees C). Processed blood and oral fluid samples were considered stable with 14.6 to 4.6 percent and 10.1 to 2.3 percent bias, respectively. For refrigerated stability, bias was 23.3 to 8.2 percent (blood) and 20.1 to 20.0 percent (oral fluid). Remifentanil exhibited >20 percent loss in both matrices. For proof of applicability, postmortem blood (n=30) and oral fluid samples (n=20) were analyzed. As a result, six fentanyl analogs were detected in the blood samples with furanyl fentanyl and 4-ANPP being the most prevalent. No fentanyl analogs were detected in the oral fluid samples. This study presents a validated screening technique for fentanyl analogs in whole blood and oral fluid using LC-QTOF-MS with low limits of detection. (publisher abstract modified)

Date Published: April 1, 2019