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1.
Molecules ; 26(4)2021 Feb 03.
Article in English | MEDLINE | ID: mdl-33546439

ABSTRACT

The rapid diffusion of new psychoactive substances (NPS) presents unprecedented challenges to both customs authorities and analytical laboratories involved in their detection and characterization. In this study an analytical approach to the identification and structural elucidation of a novel synthetic cannabimimetic, quinolin-8-yl-3-[(4,4-difluoropiperidin-1-yl) sulfonyl]-4-methylbenzoate (2F-QMPSB), detected in seized herbal material, is detailed. An acid precursor 4-methyl-3-(4,4-difluoro-1-piperidinylsulfonyl) benzoic acid (2F-MPSBA), has also been identified in the same seized material. After extraction from the herbal material the synthetic cannabimimetic, also referred to as synthetic cannabinoid receptor agonists or "synthetic cannabinoids", was characterized using gas chromatography-mass spectrometry (GC-MS), 1H, 13C, 19F and 15N nuclear magnetic resonance (NMR) and high-resolution tandem mass spectrometry (HR-MS/MS) combined with chromatographic separation. A cheminformatics platform was used to manage and interpret the analytical data from these techniques.


Subject(s)
Cannabinoids/analysis , Illicit Drugs/analysis , Nuclear Magnetic Resonance, Biomolecular , Cannabinoids/chemical synthesis , Cannabinoids/chemistry , Europe , Illicit Drugs/chemical synthesis , Illicit Drugs/chemistry , Tandem Mass Spectrometry
2.
Polymers (Basel) ; 11(3)2019 Mar 11.
Article in English | MEDLINE | ID: mdl-30960448

ABSTRACT

The use of polybutylene terephthalate (PBT) as a food contact material is increasing over the last years. Typical contaminations in the final PBT product include its cyclic oligomers, which are allowed as additives in food contact plastics according to Regulation (EU) No. 10/2011. Their investigation is currently limited by the lack of analytical standards and physical-chemical information. Therefore, four PBT cyclic oligomers have been isolated and purified from a PBT raw material with an automated preparative HPLC-DAD system. Comprehensive characterization of the compounds was performed using Ultra-High Performance Liquid Chromatography (UHPLC) with high resolution time-of-flight mass spectrometry, Fourier-Transform Infrared spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) and Nuclear Magnetic Resonance (NMR) spectroscopy. The purity of each oligomer was assessed using a ¹H qNMR method and ranged from 96.1% to 97.0% for PBT tetramer and trimer respectively. The availability of pure and well characterized PBT cyclic oligomer standards will facilitate future studies of release from plastic food packaging materials.

3.
Forensic Sci Int ; 265: 107-15, 2016 Aug.
Article in English | MEDLINE | ID: mdl-26874735

ABSTRACT

New psychoactive substances (NPS) are synthesized compounds that are not usually covered by European and/or international laws. With a slight alteration in the chemical structure of existing illegal substances registered in the European Union (EU), these NPS circumvent existing controls and are thus referred to as "legal highs". They are becoming increasingly available and can easily be purchased through both the internet and other means (smart shops). Thus, it is essential that the identification of NPS keeps up with this rapidly evolving market. In this case study, the Belgian Customs authorities apprehended a parcel, originating from China, containing two samples, declared as being "white pigments". For routine identification, the Belgian Customs Laboratory first analysed both samples by gas-chromatography mass-spectrometry and Fourier-Transform Infrared spectroscopy. The information obtained by these techniques is essential and can give an indication of the chemical structure of an unknown substance but not the complete identification of its structure. To bridge this gap, scientific and technical support is ensured by the Joint Research Centre (JRC) to the European Commission Directorate General for Taxation and Customs Unions (DG TAXUD) and the Customs Laboratory European Network (CLEN) through an Administrative Arrangement for fast recognition of NPS and identification of unknown chemicals. The samples were sent to the JRC for a complete characterization using advanced techniques and chemoinformatic tools. The aim of this study was also to encourage the development of a science-based policy driven approach on NPS. These samples were fully characterized and identified as 5F-AMB and PX-3 using (1)H and (13)C nuclear magnetic resonance (NMR), high-resolution tandem mass-spectrometry (HR-MS/MS) and Raman spectroscopy. A chemoinformatic platform was used to manage, unify analytical data from multiple techniques and instruments, and combine it with chemical and structural information.


Subject(s)
Psychotropic Drugs/analysis , Substance Abuse Detection/methods , Belgium , Crime/legislation & jurisprudence , Forensic Toxicology , Humans , Magnetic Resonance Spectroscopy , Mass Spectrometry
4.
Anal Chim Acta ; 755: 28-36, 2012 Nov 28.
Article in English | MEDLINE | ID: mdl-23146391

ABSTRACT

A new analytical strategy based on mass spectrometry fingerprinting combined with the NIST-MS search program for pattern recognition is evaluated and validated. A case study dealing with the tracing of the geographical origin of virgin olive oils (VOOs) proves the capabilities of mass spectrometry fingerprinting coupled with NIST-MS search program for classification. The volatile profiles of 220 VOOs from Liguria and other Mediterranean regions were analysed by secondary electrospray ionization-mass spectrometry (SESI-MS). MS spectra of VOOs were classified according to their origin by the freeware NIST-MS search v 2.0. The NIST classification results were compared to well-known pattern recognition techniques, such as linear discriminant analysis (LDA), partial least-squares discriminant analysis (PLS-DA), k-nearest neighbours (kNN), and counter-propagation artificial neural networks (CP-ANN). The NIST-MS search program predicted correctly 96% of the Ligurian VOOs and 92% of the non-Ligurian ones of an external independent data set; outperforming the traditional chemometric techniques (prediction abilities in the external validation achieved by kNN were 88% and 84% for the Ligurian and non-Ligurian categories respectively). This proves that the NIST-MS search software is a useful classification tool.


Subject(s)
Algorithms , Mass Spectrometry , Oils, Volatile/chemistry , Pattern Recognition, Automated , Plant Oils/chemistry , Plant Oils/classification , Geography , Olive Oil , Reference Standards , Reproducibility of Results , United States , United States Government Agencies
5.
J Agric Food Chem ; 58(9): 5586-96, 2010 May 12.
Article in English | MEDLINE | ID: mdl-20373822

ABSTRACT

(1)H NMR fingerprints of virgin olive oils (VOOs) from the Mediterranean basin (three harvests) were analyzed by principal component analysis, linear discriminant analysis (LDA), and partial least-squares discriminant analysis (PLS-DA) to determine their geographical origin at the national, regional, or PDO level. Further delta(13)C and delta(2)H measurements were performed by isotope ratio mass spectrometry (IRMS). LDA and PLS-DA achieved consistent results for the characterization of PDO Riviera Ligure VOOs. PLS-DA afforded the best model: for the Liguria class, 92% of the oils were correctly classified in the modeling step, and 88% of the oils were properly predicted in the external validation; for the non-Liguria class, 90 and 86% of hits were obtained, respectively. A stable and robust PLS-DA model was obtained to authenticate VOOs from Sicily: the recognition abilities were 98% for Sicilian oils and 89% for non-Sicilian ones, and the prediction abilities were 93 and 86%, respectively. More than 85% of the oils of both categories were properly predicted in the external validation. Greek and non-Greek VOOs were properly classified by PLS-DA: >90% of the samples were correctly predicted in the cross-validation and external validation. Stable isotopes provided complementary geographical information to the (1)H NMR fingerprints of the VOOs.


Subject(s)
Magnetic Resonance Spectroscopy/methods , Plant Oils/chemistry , Multivariate Analysis , Olive Oil , Plant Oils/standards
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