Frances Carroll (Presenter)
Restek Corporation
Authorship: Frances Carroll, Sharon Lupo, Shun-Hsin Liang, Ty Kahler, Paul Connolly
Restek Corporation, 110 Benner Circle Bellefonte, PA 16823
| Short Abstract The determination of psychoactive drugs and their metabolites has become routine in many forensic toxicology laboratories. The optimization of analysis time, resolution between metabolites, method robustness, and the ability to add emerging compounds is of ultimate importance when developing an efficient method for validation. The Raptor™ Biphenyl column combines the speed of superficially porous particles (SPP) with the resolution of highly selective USLC® technology to give the analyst the ability to produce fast dilute and shoot methods while staying current with the ever changing landscape of illegal drugs. |
Long Abstract
Background/Introduction:
The determination of psychoactive drugs and their metabolites has become routine in many forensic toxicology laboratories. The optimization of analysis time, resolution between metabolites, method robustness, and the ability to add emerging compounds is of ultimate importance when developing an efficient method for validation. The Raptor™ Biphenyl column combines the speed of superficially porous particles (SPP) with the resolution of highly selective USLC® technology to give the analyst the ability to produce fast dilute and shoot methods while staying current with the ever changing landscape of illegal drugs.
Objective:
Provide an expanded method for the fast and easy analysis of 22 synthetic cannabinoids, 12 metabolites, and salvinorin A resulting in complete resolution of isobars and separation from matrix interferences in diluted human urine.
Methods:
The method investigations were performed on a Waters Acquity I-class equipped with a Xevo TQ-S and a Shimadzu Nexera equipped with a SCIEX 4500. Both systems utilized electrospray ionization in positive ion mode. Standards were prepared in human urine and were diluted 3x in a 0.2 μm PVDF Thomson SINGLE StEP® Filter Vial with 50:50 water:methanol prior to analysis. Data was collected with MRM windows of approximately ± 30 seconds. Chromatographic optimization resulted in complete resolution of isobars and separation from major matrix interferences of a representative pooled urine sample. Water and acetonitrile mobile phases modified with 0.1% formic acid were used under gradient conditions on a Restek Raptor™ Biphenyl 2.7µm, 50 x 3.0mm column equipped with a Raptor™ Biphenyl EXP 2.7µm, 5 x 3.0mm guard.
Results:
Chromatographic separation is essential for analyzing synthetic cannabinoids JWH-018 and JWH-073 and their metabolites due to the presence of multiple positional isomers among the mono-hydroxylated metabolites. Since these positional isomers have identical molecular weights and very similar fragmentation patterns, they are indistinguishable by MS/MS detectors and chromatographic resolution is required for positive identification.
Previously a method was presented for the comprehensive screen of 17 synthetic cannabinoids, 12 metabolites and 5 internal standards with a cycle time of 5 minutes. All positional isomers were resolved on the Raptor™ Biphenyl column making it possible for the most abundant metabolites from a given parent compound to be identified in authentic samples.
Today, laboratories are faced with the difficult task of keeping up with the ever-growing list of synthetic cannabinoids illicit drug makers produce to avoid legal classification and detection. In an effort to determine the ability of the original method to keep pace with the rapidly changing list, 5 emerging synthetic cannabinoids (i.e. AB-PINACA, AB-FUBINACA, PINACA, 5F-PB-22, and PB-22) and salvinorin A were prepared in human urine and analyzed using the same methodology. The resulting chromatogram displayed all compounds eluting within the gradient and excellent retention and separation of the compounds from early-eluting matrix interferences. When the two chromatograms are over-layed, it was apparent that the compounds could easily be added to the methodology without the need for method adjustments.
Conclusion/Discussion:
The analysis of synthetic cannabinoids and their metabolites can be a difficult and challenging task. The Raptor™ Biphenyl provides solutions to the chromatographic and validation issues surrounding this analysis. It has the ability to provide highly retentive, selective, and rugged reversed-phase separations, allowing for the simultaneous analysis of 22 synthetic cannabinoids, 12 metabolites, and salvinorin A. It has been demonstrated that analyte lists can easily be expanded as new synthetic cannabinoids are introduced. The speed of SPP allows analysis times to become shorter. The unique selectivity of the biphenyl phase allows isomer separation to be easily achieved.
References & Acknowledgements:
| Description | Y/N | Source |
| Grants | yes | |
| Salary | yes | Restek Corporation |
| Board Member | no | |
| Stock | yes | Restek Corporation |
| Expenses | yes |
IP Royalty: yes
IP Desc:
| Planning to mention or discuss specific products or technology of the company(ies) listed above: | yes |