Infrared Identification of LSD and Related Compounds* Clifford C. Cromp, B.A.** and Francis C. Turney, B.A.** The new addition to Section 11901 of the California State Health and Safety Code defining some of the hallucinogenic agents as restricted dangerous drugs made necessary a rapid, simple method for determining the presence of these drugs in seized materials. The new subsection (c) reads as follows: "Lysergic acid," "LSD" (lysergic acid diethylamide) and "DMT" (N,N..cdimethyltryptamine), including their salts and derivatives, or any compounds, mixtures or preparations which are chemically identical with such substances. Although an exhaustive search of the literature was not made, review of some published methods for the identification of LSD, DMT, and related compounds indicated that thin layer chroma- tography used in conjunction with ultraviolet fluorometry (1) (2) or gas chromatography (3) had proved useful. Apparently very little information on infrared methods of identification has been published. Infrared spectra of LSD and some related compounds published by Troxler and Hofmann (4) were useful. The authors are indebted to William Arnold (5) for his preliminary investiga- tions into the extraction and infrared spectra of LSD which were instrumental in directing the line of inquiry toward the develop- ment of the method. * Presented at the Nineteenth Annual Meeting of the American Academy of Forensic Sciences, February 22, 1967, Honolulu, Hawaii. Received for publication February 22, 1967. Accepted for publication August 14, 1967. ** Los Angeles County Sheriff's Department, Physical Sciences Unit, Criminalistics Laboratory. 538 October 1967 TECHNICAL SECTION Experimental Apparatus: A Beckman IR-10 infrared spectrophotometer with beam condenser was used for recording the spectra of LSD, DMT, and related compounds. Quantities ranging from 50 to 100 micrograms of the compounds were mixed with KBr and pressed into a 1 x 5 mm pellet using the Beckman micropellet die. Procedure: Separation of the free bases was accomplished by two methods, solvent extraction and solvent extraction followed by thin layer chromatography, for both pure reference compounds and seized materials. For the solvent extraction procedure an appropriate amount of the com- pound or seized material was dissolved in 3 to 5 ml of water. The solution was made basic with a little solid sodium bicarbonate and extracted three times with 5 ml portions of spectral grade chloroform. The aqueous solu- tion was tested for completeness of extraction with long wave ultra violet light. The fluorescence normally disappeared after three chloroform ex- tractions. The combined chloroform layers were reextracted with 5 m1 of 0.01 N Hel. The acid solution was made basic with a little solid sodium bicarbonate and extracted twice with 5 ml portions of chloroform. The chloroform layers were combined and evaporated on a steam bath just to dryness in a small beaker. The residue was taken up in a few drops of chloroform and transferred to a glass well slide. After evaporation, the residue in the well slide was mixed with approximately 10 mg of finely ground spectral grade KBr. A 1 x 5 mm pellet was then made and the spectrum recorded. For the thin layer chromatography procedure, the extractions outlined above were carried out. After evaporation of the chloroform in the small beaker, the residue was taken up in a few drops of chloroform and several spots were placed on a thin layer plate coated with Alumina G. Develop- ment was carried out with 1,1,1 trichloroethane:methanol (98:2) according to the method of Dal Cortivo, et al (2). The LSD or other compound was located with ultraviolet light, the spots scraped from the plate and eluted with about 2 ml of chloroform. After centrifuging, the chloroform was transferred into a glass well slide, evaporated just to dryness and the residue prepared as a KBr pellet as described above. The spectrum was then recorded. Infrared spectra of the extracts of some seized materials obtained by the methods outlined above compared with the spectrum of known LSD are illustrated in Figures 1and 2. Vol. 12 . No.4 539 JOURNAL OF FORENSIC SCIENCES Fig. i-Infrared spectrum (KBr pellet) of LSD. Spectra and Interpretation Infrared spectra of the 27 compounds listed in Table I which include some related to the indole alkaloids, LSD and DMT, as well as some suspected to be present in some seized materials have been examined. Some of these spectra are illustrated in Figures 2-5, inc. The sources of compounds for these spectra are indi- cated by the reference following each. Tentative assignments of some of the absorption bands have been made although they are by no means exhaustive. Absorp- tion bands probably attributable to out of plane hydrogen de- formation in the indole structure are invariably present in the indole derivative spectra in the 700 cm-l to 800 cm-l region. They appear to be quite sensitive to differences in the structure asso- ciated with the indole portion and vary in frequency and intensity from compound to compound. Absorption bands attributable to amide type carbonyl structures are noted in the region 1400 cm-l to 1700 cm-'. The data available to date indicates that the spectra of LSD and DMT are sufficiently unique to allow specific identi- fication of these compounds and others related to them. 540 October 1967 TECHNICAL SECTION Fig. 2-Infrared spectra (KBr pellets) of (a) Seizure-Capsules, Solvent Extraction, (b) Seizure-Capsules, Thin-Layer Separation, (c) Seizure- Tablets, Solvent Extraction. Vol. 12 . No.4 541 JOURNAL OF FORENSIC SCIENCES Fig. 3-Infrared spectra (KBr pellets) of (a) Indole, (b) N,N-DimethyI- tryptamine and (c) Tryptophane. 542 October 1967 TECHNICAL SECTION Fig. 4-Infrared spectra (KBr pellets) of (a) Harmine, (b) d-Lysergic Acid, and (c) Ergotamine. Vol. 12 . No.4 543 JOURNAL OF FORENSIC SCIENCES Fig. 5-Infrared spectra (KBr pellets) of (a) Dihydroergotamine and (b) mescaline. 544 October 1967 TECHNICAL SECTION TABLE I COMPOUNDS WHOSE INFRARED SPECTRA HAVE BEEN EXAMINED 1. l-Acetyl-d-lysergic acid diethylamide (4) 2. Agroclavine (6) 3.Amphetamine hyrochloride (7) 4. Amphetamine sulfate (7) 5. Desoxyephedrine (7) 6. Dihydroergotamine (7) Figure 5a 7. l-Dimethylaminomethyl-d-lysergic acid diethylamide (4) 8.N,N-Dimethyltryptamine (7) Figure 3b 9. Elymoclavine (6) 10. Ergotamine (7) Figure 4c 11. Etryptamine (8) 12. Harmine (7) Figure 4a 13. I-Hydroxymethyl-d-lysergic acid diethylamide (4) 14. Indole (7) Figure 3a 15. d-Isolysergic acid diethylamide (8) 16. d-Lysergic acid (7) Figure 4b 17. d-Lysergic acid diethylamide (7) Figure 1 18. d-Lysergic acid diethylamide tartrate (7) 19. Mescaline (7~ Figure 5b 20. Methylergonovine (6) n. 1-Methyl-d-lysergic acid butanol amide (6) 22. Methysergide bimaleate (8) 23. Penniclavine (6) 24. Setoclavine (6) 25. Tartaric acid (7) 26. Tryptophane (7) Figure 3c 27. Yohimbine hydrochloride (8) Vol. 12 . No.4 545 JOURNAL OF FORENSIC SCIENCES Summary An infrared spectrophotometric method for identification of LSD, DMT, and related drugs in seizures has been presented. Methods of isolating the compounds make use of solvent extrac- tion alone or in combination with thin layer chromatography. Examination of the infrared spectra of a number of related com- pounds indicate that the specific identification of the compounds is possible. Ackrunoledinnent : Special thanks are due to Richard Bingle for providing the spectr-a of the Clavine alkaloid". REFERENCES 1. Genest, K., and C. G. Farmilo. The Identification and Determination of Lysergic Acid Diethylamide in Narcotic Seizures. J. Pharrn. Pharmacol. 16,250-257 (1964). 2. Dal Cortivo, L. A., Broich, J. R., Dihrberg , A., and B. Newman. Iden- tification and Estimation of Lysergic Acid Diethylamide by Thin Layer Chromatography and Fluorometry. Anal. Chern. 33, 1959-1960 (1966). 3.Radecka, C., and I. Nigam. Determination of Trace Amounts of Lysergic Acid Diethylamide in Sugar Cubes, J. Pharm. Sci. 55, 861-862 (1966). 4. Troxler, F., and A. Hofmann.Substitutionen am Ringsystem del' Ly- sergsaure. Helv. Chim. Acta, 40, 1706-1720 (1957). 5. Arnold, William. California State Bureau of arcotic Enforcement. Private Communication. 6. Bingle, Richard.Los Angeles Police Department, Criminalistics Labora- tory. Private Communication. 7. Spectra recorded by authors. 8. Hayden, A. L., Brannon, W. L., and C. A. Yaciw. Infrared Spectra of Some Compounds of Pharmaceutical Interest. J.O.A.C. 49, 1109-1153 (1966) . Criminalistics Laboratory Physical Sciences Unit Los Angeles County Sheriff's Department 501 North Main Street, Los Angeles, California 90012 546 October 1967.