Synthesis, Characterisation and Development of Novel, Validated Methods for the Detection and Quantification of Diphenidine- Derived New Psychoactive Substances
Total Page:16
File Type:pdf, Size:1020Kb
Synthesis, characterisation and development of novel, validated methods for the detection and quantification of diphenidine- derived New Psychoactive Substances S M O ALKIRKIT 2020 i Synthesis, characterisation and development of novel, validated methods for the detection and quantification of diphenidine-derived New Psychoactive Substances Soliman Mohamed Omar Alkirkit A thesis submitted in partial fulfilment of the requirements of the Manchester Metropolitan University for the degree of Doctor in Philosophy Department of Natural Sciences Faculty of Science & Engineering, Manchester Metropolitan University 2020 ii Abbreviations and Acronyms AA Ammonium acetate AB-CHMINACA (N-[1-Amino-3-methyl-oxobutan-2-yl]-1- [cyclohexylmethyl]-1H-indazole-3-carboxamide) 2-AI 2-Aminoindane ATR-FTIR Attenuated total reflection- Fourier Transform Infrared Spectroscopy As peak asymmetry BrDP Bromodiphenidine BZP Benzylpiperazine CHMINACA An indole-based synthetic cannabinoid CLDP Chlorodiphenidine COSY Correlation Spectroscopy CYP Cytochrome P450 enzymes Dd Doublet of doublets Ddd Doublet of doublet of doublets DAD Diode-Array Detector DAMP 4-Dimethylaminopyridine DEPT Distortionless Enhancement by Polarization Transfer DET N,N-Diethyltryptamine DIPH Diphenidine DMSO-d6 Dimethyl sulfoxide-d6 DP Diphenidine DPD Diphenidine DPH Diphenidine ii 2-EAPB 2-(2-Ethylaminopropyl) benzofuran EMCDDA European Monitoring Centre for Drugs and Drug Addiction EU European Union EWS Early Warning System ɛ Molar absorptivity FDP Fluorodiphenidine FCEP Fluorocyanoephenidine FEP Fluephenidine FTIR Fourier-transform infrared spectroscopy GC Gas Chromatography Gas chromatography electron ionisation mass GC-EI-MS spectrometry GC-MS Gas chromatography-mass spectrometry Liquid chromatography–high resolution mass LC-HR-MS spectrometry Liquid chromatography coupled with multistage accurate LC-MS(n) mass spectrometry (LC–MSn) GDS Global Drug Survey H Height equivalent per theoretical plate halo DP Halogenated diphenidine HCG Human Chorionic Gonadotropin HCl Hydrochloride HIV Human Immunodeficiency Virus H(m) Height equivalent to a theoretical plate HMBC Heteronuclear Multiple Bond Coherence iii HMQC Heteronuclear Multiple Quantum Coherence HPLC High Performance Liquid Chromatography Hz Hertz IDP Iododiphenidine International Conference on Harmonisation of Technical ICH Requirements of Pharmaceutical for Human Use i.d. Internal diameter IR Infra-Red IUPAC International Union of Pure and Applied Chemistry K Capacity factor LC Liquid Chromatography LCMS Liquid Chromatography Mass Spectroscopy LOD Limit of Detection LOQ Limit of Quantification LSD Lysergic acid diethylamide M Molar M Metre(s) MAA Methacrylic acid MALDI-Q- Matrix-assisted laser desorption ionization (MALDI) TOF/MS quadrupole time-of-flight (Q-TOF)/MS MANDRAKE MANchester DRug Analysis & Knowledge Exchange MBOMe N-Methoxybenzyl MDA Misuse of Drugs Act MDMA 3,4-Methylenedioxymethamphetamine mM Millimolar iv MHz Megahertz Min Minute(s) MIP Molecularly imprinted polymer MDDP Methylenedioxydiphenidine MDMA 4-Methylenedioxymethamfetamine MgSO4 Magnesium sulfate MMC Mephedrone (or 4-methyl methcathinone) MP Mobile phase MPA Methiopropamine Mpt Melting point MS Mass Spectroscopy MXE Methoxetamine MXP Methoxphenidine m/z Mass-to-charge ratio N Column efficiency NMR Nuclear magnetic resonance NMDAR N-methyl-D-aspartate receptor NPS New psychoactive substances PCP Phencyclidine Logarithm of the reciprocal of the hydrogen ion pH concentration PMMA p-Methoxymethamphetamine Ppm Parts per million PSA Psychoactive Substances Act r2 R-squared (regression) v Rf Retention factor RP Reverse (or reversed) phase RPLC Reverse (or reversed) phase liquid chromatography RRf Relative Retention factor RRT Relative retention time Rs Resolution RSD Relative standard deviation tR Retention time SS Street sample t0 HPLC Column Dead Time TEAP Triethylammonium phosphate TFA Trifluoroacetic acid TFMXP Trifluoromethoxphenidine THC Tetrahydrocannabinol TLC Thin-Layer Chromatography UNAIDS United Nations Programme on HIV and AIDS UNODC United Nations Office on Drugs and Crime Ultra-performance liquid chromatography-electrospray UPLC-ESI-MS tandem mass spectrometry Ultra-performance liquid chromatography-tandem mass UHPLC-MS/MS spectrometry (UPLC-MS/MS UV Ultra-violet UV-DAD Ultra-violet/Diode Array Detection UV-vis Ultra-violet-visible v/v Volume by volume vi WHO World Health Organisation w/v Weight by volume vii Acknowledgements I would like to thank Dr Oliver B. Sutcliffe and Dr Ryan E. Mewis for their constant and invaluable advice throughout this project along with their research teams for their continued support throughout the project and to Manchester Metropolitan University for the use of their facilities and the technical staff for help in the laboratory. Also many thanks to the Libyan Government for the scholarship and support and to my wife and family for their continued support during the years of my studies and research. viii Abstract There is a worldwide increase in the abuse of new psychoactive substances, which pose a threat to public health. The fast‐paced nature of the NPS market and increased availability is drawing international concern. There is a general lack of comprehensive evidence on the toxicity and abuse risks associated with long-term use. The rapid pace of NPSs development means that they remain as an area of concern and interest; this shows the technical challenges in terms of development of analytical methods for the detection and determination of these substances. There is a knowledge gap in terms of chromatographic methods of detection, separation and quantification of diphenidine and its derivatives, in particular HPLC approaches. Currently, there is more research applying GC methods for NPSs analysis. The aim of this project is to develop a reliable, rapid, sensitive and robust HPLC method for the analysis of this group of NPSs. Regioisomeric compounds, 2-, 3- and 4-methoxphenidine (MXP) were used to develop a robust high performance liquid chromatography (HPLC) method using mobile phase (acetonitrile:ammonium acetate 55:45% v/v) whilst the stationary phase was ACE-5 C18 AR column (150 x 4.6 mm, 5 µm particle size). The method was validated according to the International Conference on Harmonisation of Technical Requirements of Pharmaceutical for Human Use (ICH) guidelines and shown to be both selective and sensitive (Limit of Detection, LOD = 0.04-0.15 µg mL-1, Limit of Quantification, LOQ = 0.38-0.47 µg mL-1). The reference materials used for this study were characterised using 1H NMR, 13C NMR, IR, UV and GC-MS. The scope of the study was applied to the recently reported diphenidine derivatives, 2-, 3- and 4-fluephenidines, in addition to 2-, 3- and 4- fluorocyanophenidines and the halogenated diphenidine compounds. ix Accuracy, precision, robustness and specificity of these substances were investigated. As an average, limit of detection (LOD) was between 0.05 and 0.60 µg mL-1, whereas, limit of quantification (LOQ) was between 0.16-1.84 µg mL-1 for all the diphenidine derived regioisomers tested in this study. Additionally, total run time of just 10 minutes with resolution values (Rs) of greater than 2 in the case of both MXP isomers and all tested halogenated diphenidine isomers indicates that the applied HPLC method was rapid and sensitive, therefore it can be implemented to examine any samples that might contain these substances. x Chapter 1: Introduction and literature review ........................................... 1 1.1 Laws controlling substances of concern in the UK ................................... 1 1.1.1 The Misuse of Drugs Act 1971 (MDA 1971) ....................................... 3 1.1.2 Misuse of Drugs Regulations 1985 .................................................... 4 1.1.3 The Misuse of Drugs Regulations 2001 ............................................. 6 1.2 Popularity of NPS ................................................................................... 10 1.3 Prevalence of NPS ................................................................................. 11 1.3.1 Psychoactive Substances Act (2016) ............................................... 15 1.3.2 Changes in the NPS market since the introduction of the PSA (2016) .................................................................................................................. 19 1.4 Classification of NPS .............................................................................. 21 1.5 Diphenidine (legal status, chemistry, synthesis, pharmacology, toxicology, metabolism and intoxication) ........................................................................ 22 1.5.1 The legal status of diphenidine and its derivatives ........................... 23 1.5.2 Chemistry of diphenidine .................................................................. 24 1.5.3 Synthesis of diphenidine .................................................................. 25 1.5.4 Pharmacology of diphenidine ........................................................... 26 1.5.5 Toxicology of diphenidine ................................................................. 27 1.5.6 Metabolism of diphenidine................................................................ 28 1.5.7 Intoxications by diphenidine ............................................................. 29 1.6 Methods of analysis of NPS/diphenidine derivatives .............................. 31 1.7 Chromatography ....................................................................................