Understanding the Method and Results from the Analysis of Fentanyl in Postmortem Blood Using Biocompatible Solid-Phase Microextraction

The use of the Biocompatible Solid-Phase Microextraction (BioSPME) fiber in Grant et al. original work was to create an analysis method that is faster and simpler in identifying fentanyl in postmortem blood than current analysis methods.  While the study was able to demonstrate that fentanyl was able to be absorbed onto the fiber and analyzed through the use of GC-MS and LC-MS-MS, the data reported was beyond the sensitivity for both instruments.  The purpose of this communication is to provide more information regarding the methodology and sensitivity for both instruments and to reinterpret the data when comparing to the results from Health Network Laboratories.  Based on the reinterpreted data, this current method was consistent with the results from Health Network Laboratories in identifying fentanyl in postmortem blood concentration equal to or greater than 21.4 ng/mL.