Unique Structural/Stereo-Isomer and Isobar Analysis of Novel Fentanyl Analogues in Postmortem and DUID Whole Blood by UHPLC-MS-MS.

The presented analytical method enabled the Toxicology Department at the Cuyahoga County Medical Examiner's Office to identify 26 and quantitatively report 24 compounds in 500 µL of whole blood, including fentanyl analogues (fentalogues) such as methoxyacetyl fentanyl (MeOAF) and cyclopropyl fentanyl (CPF). This second-generation method (FG2) was developed with the objective to improve the existing analysis (FG1) by decreasing sample size, lowering limits of detection (LOD) and lower limit of quantitation, minimizing ion suppression and resolving chromatographic interferences. Interferences may occur in the analysis of fentanyl, MeOAF, CPF, 3-methylfentanyl (3MF), butyryl fentanyl and isobutyryl fentanyl due to isobars and structural or geometric isomerism with another analogue or metabolite. The isomeric and isobaric fentalogues were grouped into three sets. The LOD established for Set 1 [MeOAF, para-methoxyacetyl fentanyl, para-fluoro acryl fentanyl (isobar), fentanyl carbamate], 2-furanyl fentanyl, Set 2 [CPF, (E)-crotonyl fentanyl] and carfentanil was 0.0125 ng/mL. The LOD established for N-methyl norfentanyl, norfentanyl, norcarfentanil, despropionyl fentanyl (4-ANPP), acetyl fentanyl, ß-hydroxy fentanyl, benzyl fentanyl, acryl fentanyl, alfentanil, fentanyl, para-fluoro fentanyl, Set 3 [(±)-trans-3MF, (±)-cis-3MF, isobutyryl and butyryl fentanyl], para-fluoroisobutyryl fentanyl, sufentanil, phenyl fentanyl and cyclopentenyl fentanyl was 0.0625 ng/mL. Seven-point linear calibration curves were established between 0.025 and 4.0 ng/mL for the 8 analytes with the lower LOD and 0.125 and 20 ng/mL for the 18 analytes with the higher LOD. 4-ANPP and cyclopentenyl fentanyl met qualitative reporting criteria only. The results for five postmortem and two driving under the influence of drugs authentic case samples are presented. To the authors' knowledge, FG2 is the first published method that achieved baseline resolution of the nine structural/stereo isomers and one isobar by ultra-high performance liquid chromatography-MS-MS and provided quantitative validation data for nine compounds. FG2 may be used as the new baseline for future isomers that need to be chromatographically separated.

Long-term stability of ethanol solutions for breath-alcohol tests.

Aqueous alcohol solutions in conjunction with a simulator are used commonly to calibrate and check the operation of breath-alcohol instruments. In Ohio, these solutions expire one year from the date of manufacture. This study was undertaken to review and report the stability of several batches of solution that had been manufactured from 2003 to 2007 and were statutorily expired. Eight batches of solution, each with a theoretical breath-alcohol target value of 0.100 g/210 L, were tested on paired Intoxilyzer 8000s using Guth model 590 simulators. This model of simulator required only 250 mL of solution per simulator. Therefore, each batch was evaluated by testing a single bottle of solution that had remained sealed since its manufacture. Five tests were performed on each instrument, and the acceptable criterion was limited to +/- 0.005 g/210 L of the established target value. A current batch of solution was also examined to verify the performance of the instrument before study sample testing commenced and at the completion of testing. All batches and bottles produced acceptable results within the acceptable limit for each target value. It can be concluded that the stability of the wet bath solution packaged in high-density polyethylene bottles with a theoretical concentration of 0.100 g/210 L is in excess of five years and surpasses the statutory expiration term of one year from the date of manufacture when stored at normal room temperatures.