Recommended methods for the identification and …

1 Recommended methods for the identification and Analysis of barbiturates and benzodiazepines under international ControlManual for use by national drug analysis laboratoriesPhoto credits:UNODC Photo Library; UNODC/Ioulia Kondratovitch; Alessandro and Scientific SectionUnited nationS office on drUgS and crimeViennaRecommended methods for the identification and Analysis of barbiturates and benzodiazepines under international ControlMANUAL FOR USE BY NATIONAL DRUG ANALYSIS LABORATORIESUNITED NATIONSNew York, 2012iiNoteOperating and experimental conditions are reproduced from the original reference materials, including unpublished methods , validated and used in selected national laboratories as per the list of references. A number of alternative conditions and substitution of named commercial products may provide comparable results in many cases, but any modification has to be validated before it is integrated into laboratory routines.

2 Mention of names of firms and commercial products does not imply the endorse-ment of the United Nations. United Nations, June 2012. All rights designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Secretariat of the United Nations concerning the legal status of any country, territory, city or area, or of its authorities, or concerning the delimitation of its frontiers or publication has not been formally production: English, Publishing and Library Section, United Nations Office at UNODC Laboratory and Scientific Section (LSS, headed by Dr. Justice Tettey), wishes to express its appreciation and thanks to Professor Alexander Gray, Strath-clyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, United Kingdom, for the preparation of the first draft of the present manual, and to Dr Pirjo Lillisunde, Head of Drug Laboratory, National Institute for Health and Welfare, Finland, for the expert review of the document.

3 The preparation of this manual was coordinated by Dr. Iphigenia Naidis, staff member of LSS. The contri-bution of other UNODC staff is gratefully .. iiiIntroduction .. 1 Background .. 1 Purpose and use of the manual .. 1I. barbiturates .. 31. Classifications and definitions .. 32. Description of pure compounds .. 43. Qualitative and quantitative analysis of materials containing barbiturates .. Sampling.. Extraction and sample preparation .. Presumptive tests .. Thin-layer chromatography (TLC) .. Gas chromatography (GC) with flame ionization detector (FID) Gas chromatography - mass spectrometry (GC-MS) .. High performance liquid chromatography (HPLC).

4 Infrared spectroscopy .. 19II. benzodiazepines and related substances .. 211. Classifications and definitions .. 212. Description of pure compounds (see also annex II).. 223. Qualitative and quantitative analysis of materials containing benzodiazepines .. Sampling.. Extraction and sample preparation .. Presumptive tests .. Thin-layer chromatography (TLC) .. Gas chromatography (GC) with flame ionization detector (FID) Gas chromatography - mass spectrometry (GC-MS) .. High performance liquid chromatography (HPLC) .. Infrared spectroscopy .. 35viPageReferences .. 37 Further reading .. 40 AnnexI. Description of barbiturates under international control .. 42II. Description of benzodia zepines under international control.

5 491 Introduction BackgroundBarbiturates and benzodiazepines are used in medicine as anticonvulsants, anxioly-tics, hypnotics, sedatives, skeletal muscle relaxants and tranquilizers. Currently, twelve barbiturates and thirty-five benzodiazepines are under international control. Those that have found their way into illicit use have mainly been diverted from the licit market. Seizures of benzodiazepines and barbiturates increased by more than 50 per cent between 2005 and 2009 according to the World Drug Report 2011 [1]. The use of benzodiazepines is common among drug users, including substitution treatment clients. The non-medical use of barbiturates , benzodiazepines and other sedatives together with opioids has been a commonly observed phenomenon in many regions.

6 The existence of parallel markets is observed, where prescription drugs are sold outside the control of the health authorities as well as through illegally operating Internet pharmacies. benzodiazepines , specifically aprazolam and diazepam, are among the most often diverted and abused psychotropic substances [2]. However, given the absence of information on overall drug use patterns, it is difficult to estimate the extent of non-medical prescription drug use worldwide. Purpose and use of the manualThe present manual is one in a series of similar UNODC publications dealing with the identification and analysis of various types of drugs under international control. These manuals are the outcome of a programme pursued by UNODC since the early 1980s, aimed at the harmonization and establishment of Recommended methods of analysis for national drug analysis present manual combines and updates the two existing manuals on Recommended methods for testing barbiturate derivatives [3] and benzodiazepine derivatives [4] under international control, published in 1989 and 1989 respectively.

7 It has been prepared taking into account developments in analytical technology with a view to 2 Recommended methods for the identification and Analysis of barbiturates and Benzodiazepinesproviding the basis for reliable forensic evidence on seized materials containing barbiturate or benzodiazepine derivatives. It is divided into two parts which provide analytical methodologies for the two types of substances with reference to validated techniques. Description of the individual barbiturates and benzodiazepines under international control is provided in two annexes. In line with the overall objective of the series of UNODC publications, this manual suggests approaches that may assist drug analysts in the selection of methods appro-priate to the sample under examination and provide data suitable for the purpose at hand, leaving room also for adaptation to the level of sophistication of different laboratories and the various legal needs.

8 Therefore, the methods described here should be understood as practical guidance, that is, minor modifications to suit local circumstances should normally not change the validity of the results. Not all methods described in this manual need to be applied to all samples suspected to consist of or contain barbiturates or benzodiaze-pines. The choice of the methodology and approach to analysis as well as the deci-sion as to whether or not additional methods are required remain with the analyst and may also be dependent on the availability of appropriate instrumentation and the level of legally acceptable proof in the jurisdiction within which the analyst works. The reader should be aware that there are a number of other methods , includ-ing those published in forensic science literature, which may also produce acceptable results.

9 However, any new method that is about to be used in a laboratory must be validated and/or verified prior to routine use. Attention is also drawn to the importance of the availability to drug analysts of reference materials and literature on drugs of abuse and analytical techniques. More-over, the analyst must of necessity keep abreast of current trends in drug analysis, consistently following current analytical and forensic science Laboratory and Scientific Section welcomes observations on the contents and usefulness of the present manual. Comments and suggestions may be addressed to:Laboratory and Scientific SectionUnited Nations Office on Drugs and CrimeVienna international Box 5001400 ViennaAustriaFax: (+43-1) 26060-5967E-mail: manuals, as well as guidelines and other scientific-technical publications may be requested by contacting the address BarbituratesThe abuse of barbiturates is widespread and it has often been found mixed with other substances of abuse such as heroin.

10 The international nature of the illicit market means that any forensic laboratory may encounter a range of these compounds. However, virtually all of the barbiturates in the illicit market result from diversion from legitimate sources and there is no reported evidence of clandestine manufacture. The twelve barbiturate derivatives under international control (1971 Convention on Psychotropic Substances) appear mainly as capsules and tablets. Some are marketed in other pharmaceutical forms such as elixirs, injectable solutions and sterile powders for injection. Pentobarbital sodium is available in some countries as rectal supposi-tories and barbital sodium is commonly sold in powder form. barbiturates often occur as mixtures with other barbiturates ( amobarbital/secobarbital), with other drugs ( aspirin, caffeine, codeine, ephedrine, theophylline) and with attendant pharmaceutical excipients.