T2007 Seattle, Washington

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1 T2007 Seattle, Washington Application of Liquid Chromatography-Mass Spectrometry with Atmospheric Pressure Chemical Ionization as a Screening Method for forty-two Date-Rape Drugs Piotr Adamowicz*, Maria Kala Institute of Forensic Research, ul. Westerplatte 9, Krakow, Poland Piotr Adamowicz ul. Westerplatte Krakow Tel.: Fax.: padamowi@ies.krakow.pl * Author to whom correspondence should be addressed Abstract The phenomenon of drug-facilitated crimes (sexual assaults, robbery) is common in many countries. Because of wide variety of substances used as date-rape drugs, their low concentration in blood and the long delay between the alleged crime and clinical examination, analysis of biological fluids collected from victims of rapes for presence of these drugs was rare up to now. The aim of this study was to develop and apply a LC-APCI- MS screening procedure for date-rape drugs in blood. Target analytes were isolated using liquid-liquid extraction. Analyses were carried out using an Agilent LC/MS operating in APCI mode. Detection of all compounds was based on pseudomolecular ions that were monitored in 6 groups up to 19 ions in each group. Accuracy of the method was verified in the Qualitative Screening Analysis Program of the International Proficiency Testing Scheme with clonidine assigned concentration of 50 ng/ml. The procedure can be easily expanded for more substances. The LC-APCI-MS procedure was successfully applied to the analysis of authentic blood samples collected from victims of rapes in routine casework. Keywords: Drug-facilitated sexual assault, Drug screening, LC-APCI-MS INTRODUCTION Because of pharmacological properties, especially inducing amnesia, many drugs have been identified as so-called date-rape drugs for the purpose of drugging unsuspected victims and than raping them. In a typical scenario, the perpetrator surreptitiously adds date-rape drug to the alcoholic or non-alcoholic beverage of an unsuspecting person, who is subsequently sexually assaulted while under the influence of this substance. Many victims do not report the incident until several days after the event or even do not report it at all. They report the incident so late

2 after the events because they often have problems with remember the course of incident. It causes that victim is not reliable witness for justice. Indicating of presence date-rape drugs in biological fluids is unequivocal evidence of perpetration [6, 8, 10]. Since the beginnings of twenty-first century in Poland increasing number of reports about the drug facilitated sexual assaults have appeared. This increasing tendency is attested to by increasingly frequent domestic press reports on the use of drugs to facilitate sexual assault. This problem is also reflected in the practice of the Institute of Forensic Research in Cracow [1, 2, 3, 5]. In , 128 of this kind of cases were analyzed in the Department of Toxicological Analyses. After 2003 significant increase of these cases was observed, and recently, between 20 and 40 of cases involving date-rape drugs were registered every year. These cases were submitted to the Institute to carry out analyses for presence of narcotic drugs, psychotropic substances and medicine drugs that could have an influence for behaviour of persons. At present, blood is the main material delivered for investigation. Concentrations of many drugs in this material are low. Moreover victims report the incident late [4, 7, 9]. Because of these many analytical laboratory methods do not allow for detection of date-rape drugs. This situation creates a demand for selective and sensitive analytical screening method to prove the presence of the drug in blood collected from the victim. MATERIALS AND METHODS Chemicals All tested drug standards and deuterated analogues were purchased from Cerilliant Corporation (LGC Promochem, Warszawa, Poland) and from Sigma (Sigma-Aldrich Polska, Poznan, Poland). Biological material Drug-free blood (control blood sample) was taken from a local blood bank and was used for the development and validation of the method. Forensic blood samples were from routine casework elaborated at the Institute of Forensic Research in Cracow.

3 Liquid-Liquid Extraction Clonazepam-D4, estazolam-d5 and MDMA-D5 were added to two blood samples (0.5 ml each) in eppendorf vials (achieving concentration of 500 ng/ml of each internal standard). Than phosphate buffer ph 2.0 (0.3 ml) and diethyl ether (1.0 ml) were added to one sample (for acidic drugs). Carbonate buffer ph 9.0 (0.5 ml) and ethyl acetate were added to the second one (for basic drugs). Samples were shaken for 5 minutes. After centrifugation at 6000xg for 3 min organic layers were successively evaporated to dryness under a stream of nitrogen on heating block at 37 o C in one vial. The dry residue was reconstituted in 200 μl of mobile phase consisted of acetonitile-water (1:1, v/v). APCI-LC-MS Analysis Analysis was carried out using a Agilent Technologies Series 1100 LC-MS instrument with atmospheric pressure chemical ionisation (APCI) interface (Hewlett Packard, Wilmington, USA). The separation was performed with the use of a LiChroCART Purospher STAR RP-18e 125 x 4 mm (Merck, Darmstadt, Germany) thermostated at 25 o C. The mobile phase consisted of water and acetonitrile (AcCN) containing 0.1 % (v/v) formic acid. The flow rate was 1.0 ml/min. All analyses were carried out in gradient mode: 0 min 5% AcCN, 20 min 60% AcCN, 21 min 80% AcCN, 23 min 80% AcCN, 24 min 5%, 30 min 5%. The injection volume of the solution was 20 μl. Settings of MSD: positive ions mode, fragmentor voltage 60 V, vaporizer temperature 325 o C, capillary voltage 4000 V, drying gas flow 4 L/min and temperature 320 o C, nebulizer pressure 30 psi, corona current 4.0 μa.

4 RESULTS AND DISCUSSION The LC-APCI-MS method for the simultaneous screening, detection and quantification of forty-two compounds was developed. The list of date-rape drugs was prepared on the basis of literature and own casework. This list does not contain GHB, related compounds, and barbiturates for which LC-APCI-MS is not a method of choice. Detection of all compounds was based on pseudomolecular ions that were monitored in 6 groups up to 19 ions in each group. Monitored ions, and retention times of all compounds are presented in Table I. Ions for compounds that had retention times ± 1 minute from end or beginning of group were monitored in both neighbouring groups. The drugs were quantified in the SIM mode. No interfering peaks were observed in the extracts of eight blank blood samples. Twenty potential interfering compounds were individually spiked into low quality in-house control samples. All controls quantified within ± 20% of target values and showed no interferences with analytes or internal standards. The LODs with a S/N 3 were determined in the range of ng/ml in the SIM mode. The LOQs corresponded to the lowest calibrator concentrations with S/N 10. The assay was linear from subtherapeutic ( ng/ml, 22 compounds) or low therapeutic concentrations (2-10 ng/ml, 14 compounds) up to 1 μg/ml (42 compounds). Linear regression correlation coefficients of the 9-point calibration curves (n=5) were In reconstituted extracts the analytes were stable for a period of more than 24 hours at room temperature or for 3 days at 20 0 C. The procedure can be easily expanded for more substances. Accuracy of the method was verified in the Qualitative Screening Analysis Program of the International Proficiency Testing Scheme. Using described method in tested serum sample clonidine was detected and determined at concentration of 43.0 ng/ml. On the basis of result report was known that tested serum was spiked with clonidine at concentration of 50.0 ng/ml and mean value determined by participating laboratories was 40.4 ng/ml The procedure was also successfully applied to the analysis of authentic blood samples collected from victims of rapes in routine casework. In one case morphine at concentration of 23 ng/ml and diazepam at concentrations of 8 ng/ml were found. CONCLUSIONS Recently, in Poland, an increase number of drug facilitated sexual assaults has been observed. In this context the sensitive LC-APCI-MS method for detection of date-rape drugs in blood was developed. Low limits of detection of the method allows for analysis of samples even after long delay between the alleged crime and collection of biological fluids. The procedure was successfully applied to the analysis of authentic blood samples collected from victims of rapes in routine casework. The procedure can be easily modified for more drugs. The method is quantitative screening and positive results should be confirmed by other method because applied equipment allows for monitoring only one ion for each compound in SIM mode.

5 References: 1. Adamowicz P., Toxicological Analysis In Cases of Facilitation of Rape by Administration of Pharmacological Compound, in Polish, Problemy Kryminalistyki 2005, 248, Adamowicz P., Kała M., Date-Rape Drugs Scene in Poland, Przegląd Lekarski, 2005, 62/6, Adamowicz P., Kała M., Drugs and Alcohol as Agents Used for Facilitation of Sexual Assault, Problems of Forensic Sciences 2004, 58, Adamowicz P., Kała M., Urinary excretion rates of ketamine and norketamine following therapeutic ketamine administration: method and detection window considerations, Journal of Analytical Toxicology 2005, 28, Adamowicz P., Zuba D., Kała M., Ketamine: A new substance on the Polish drug market. Problems of Forensic Sciences, 2003, 56, ElSohly M.A., Salamone S.J.: Prevalance of drugs used in cases of alleged sexual assault. Journal of Analytical Toxicology, 1999, 23, Kasprzak K., Adamowicz P., Kała M., Determination of Gamma-Hydroxybutyrate (GHB) in Urine by Gas Chromatography-Mass Spectrometry with Positive Chemical Ionization (PCI- GC-MS) Method, Problems of Forensic Sciences 2006, 67, LeBeau M.A., Mozayani A., Drug-facilitated sexual assault. A forensic handbook. Academic Press, Negrusz A., Adamowicz P., Saini B.K., Webster D.E., Juhascik M.P., Moore Ch.M., Schlemmer R.F., Detection of ketamine in urine of nonhuman primates after single dose using microplate enzyme-linked immunosorbent assay (ELISA) and NCI-GC-MS, Journal of Analytical Toxicology 2005, 29, s Negrusz A., Gaensslen R.E.: Toxicological investigations in drug-facilitated sexual assault, Problems of Forensic Sciences, 2000, 41, 7-26.

6 Table I. Ion groups, monitored ions in SIM mode, and retention times of all analyzed compounds TIME (min) GROUP ION (m/z) RETENTION TIME (min) COMPOUND Morphine Clonidine Codeine Amphetamine Scopolamine MDA Metamphetamine PMA MDMA-d5 (ISTD 1) MDMA Zopiclone Lidocaine Ketamine Ibuprofen Cocaine PCP Zolpidem Clozapine Meprobamate Fentanyl Midazolam Diphenhydramine Buprenorphine Doxepin Haloperidol Desipramine Imipramine Hydroxyzine Nortryptyline Amitryptyline Fluoxetine Trimipramine Methadone

7 Oxazepam Sertraline Estazolam-d5 (ISTD 2) Lorazepam Clonazepam-d4 (ISTD 3) Alprazolam Clonazepam THC Promethazine Temazepam Flunitrazepam Diazepam Figure 1. Selected ion chromatograms of the extract of blood spiked with 42 analyzed compounds and 3 internal standards to the concentration of 500 ng/ml (for fentanyl to 25 ng/ml). 1 morphine; 2 clonidine; 3 codeine; 4 amphetamine; 5 scopolamine; 6 MDA; 7 metamphetamine; 8 PMA; 9 MDMA-D5; 10 MDMA; 11 zopiclone; 12 lidocaine; 13 ketamina; 14 ibuprofen; 15 cocaine; 16 PCP; 17 zolpidem; 18 clozapine; 19 meprobamate; 20 midazolam; 21 fentanyl; 22 diphenhydramine; 23 buprenorphine; 24 doxepin; 25 haloperidol; 26 desipramine; 27 imipramine; 28 hydroxyzine; 29 nortryptyline; 30 amitryptyline; 31 fluoxetine; 32 trimipramine; 33 oxazepam; 34 - methadone; 35 estazolam-d5; 36 sertraline; 37 lorazepam; 38 alprazolam; 39 clonazepam-d4; 40 clonazepam; 41 9THC; 42 flunitrazepam; 43 promethazine; 44 temazepam; 45 diazepam. Figure 1.

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