title: An analytical approach to the forensic identification of different classes of new psychoactive substances (NPSs) in seized materials.
abstract: BACKGROUND
  New psychoactive substances (NPSs) are rapidly spreading worldwide, and forensic laboratories are often requested to identify new substances for which no reference standards or analytical data are available. This article describes an analytical approach that was adopted in Italy by a few collaborative centres of the Italian Early Warning System for Drugs, which has contributed many alerts for the identification of different classes of NPSs in the last 24 months.
  
  
  METHODS
  Seized crystals and powders were initially analysed via single quadrupole gas chromatography/mass spectrometry (GC/MS), followed by liquid chromatography/high-resolution mass spectrometry (LC/HRMS) in the positive electrospray ionisation (ESI) mode at 100,000 full width at half maximum resolution (FWHM) without fragmentation to elucidate the elemental compositions of unknown molecules. Different fragmentation voltages during LC/HRMS were applied to study the accurate masses of the obtained characteristic fragments. Nuclear magnetic resonance (NMR) analyses were performed to identify specific isomers when necessary.
  
  
  RESULTS
  Some interesting examples of unknown NPSs from seizures later identified in our laboratories are reported, with special focus on those cases where analytical standards were not available during analyses. These cases include cathinones, such as 3-methylmethcathinone (3-MMC), methylone, bk-MBDB (butylone), 4-methylethcathinone (4-MEC), flephedrone, methylenedioxypyrovalerone (MDPV) and pentedrone, methoxetamine, apinaca or AKB48, benzydamine, meta-chlorophenylpiperazine (m-CPP), 5-MeO-N,N-dialkyl tryptamines, such as 5-MeO-DALT and 5-MeOMIPT, benzofurans, such as 6-APB and 4-APB, and diphenidine (identified for the first time in Europe).
  
  
  CONCLUSIONS
  The identification of NPSs in confiscated materials was successfully achieved via GC/MS coupled with LC/HRMS and, in a few cases, NMR analyses. The availability of GC/MS libraries is of great assistance in the identification of new drugs. Alternatively, the study of characteristic molecule fragments combined with the determination of their accurate masses can be a useful approach to identify unknown samples not previously analysed.
authors.affiliation: Institute of Public Health, Section of Legal Medicine, Università Cattolica del Sacro Cuore, Rome, Italy L.go F. Vito 1, 00168, Rome, Italy.
authors.forename: Sabina
authors.initials: S
authors.lastname: Strano Rossi
authors.forename: Sara
authors.initials: S
authors.lastname: Odoardi
authors.forename: Adolfo
authors.initials: A
authors.lastname: Gregori
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Peluso
authors.forename: Luigi
authors.initials: L
authors.lastname: Ripani
authors.forename: Giorgio
authors.initials: G
authors.lastname: Ortar
authors.forename: Giovanni
authors.initials: G
authors.lastname: Serpelloni
authors.forename: Francesco Saverio
authors.initials: FS
authors.lastname: Romolo
mesh_terms: D000470:Alkaloids / Q000032:analysis; D001572:Benzofurans / Q000032:analysis; D002853:Chromatography, Liquid; D015198:Designer Drugs / Q000032:analysis*; D044707:Forensic Sciences / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D010879:Piperazines / Q000032:analysis; D011619:Psychotropic Drugs / Q000032:analysis*; D014363:Tryptamines / Q000032:analysis
chemical_list: D000470:Alkaloids; D001572:Benzofurans; D015198:Designer Drugs; D010879:Piperazines; D011619:Psychotropic Drugs; D014363:Tryptamines; C023665:cathinone; C015068:1-(3-chlorophenyl)piperazine