Detection and identification of drugs and toxicants in human body fluids by liquid chromatography-tandem mass spectrometry under data-dependent acquisition control and automated database search.

Systematic toxicological analysis (STA) is aimed at detecting and identifying all substances of toxicological relevance (i.e. drugs, drugs of abuse, poisons and/or their metabolites) in biological material. Particularly, gas chromatography-mass spectrometry (GC/MS) represents a competent and commonly applied screening and confirmation tool. Herein, we present an untargeted liquid chromatography-tandem mass spectrometry (LC/MS/MS) assay aimed to complement existing GC/MS screening for the detection and identification of drugs in blood, plasma and urine samples. Solid-phase extraction was accomplished on mixed-mode cartridges. LC was based on gradient elution in a miniaturized C18 column. High resolution electrospray ionization-MS/MS in positive ion mode with data-dependent acquisition control was used to generate tandem mass spectral information that enabled compound identification via automated library search in the "Wiley Registry of Tandem Mass Spectral Data, MSforID". Fitness of the developed LC/MS/MS method for application in STA in terms of selectivity, detection capability and reliability of identification (sensitivity/specificity) was demonstrated with blank samples, certified reference materials, proficiency test samples, and authentic casework samples.

[Impact of slow-release oral morphine on drug abusing habits in Austria]. / Der Einfluss von retardiertem Morphin auf die Drogensituation in Osterreich.

A well-established possibility to treat opiate addiction is the participation in opiate maintenance treatment programmes. For this purpose the opioids methadone and buprenorphine have been evaluated and are used nowadays in many countries. However, since 1998 also the use of slow-release oral morphine (SROM) has been legally permitted in Austria. Our data show that these morphine preparations are frequently abused and are dominating the black market in the meantime. Especially the intravenous consumption of SROM goes along with highly dangerous side effects that exceed the risks of needle sharing alone. Special galenics are supposed to ensure a 24 h effect of the otherwise quickly metabolised morphine. If dissolved and injected, insoluble contents such as talcum cause microembolisms, leading to severe damages of the inner organs. Furthermore, SROM, i.e. a drug prescribed by physicians, has been proved to be the main responsible substance in most drug related deaths since its permission and has nearly replaced heroin. Forensic physicians play a major role in the profound examination of these cases, including extensive toxicological analyses and interpretation of results. For instance, a differentiation between a recent morphine and heroin consumption is certainly possible, provided appropriate methods are used. A reliable estimation of the current situation of drug abusing habits is a premise for adequate therapeutic offers and preventive measures. Thus, well-founded and comparable data have to be collected. To facilitate data report a standardized report form has been developed that includes an obligatory statement regarding morphine or heroin consumption. This should help to enlighten the ongoing discussion on the role of SRM in drug abuse cases. Our results indicate that the prescription of SROM in opiate maintenance therapy has to be handled very strictly and should be reserved for special patients only. A slackening of the Austrian law concerning SROM is therefore objected.

A fatal intoxication case involving topiramate.

Topiramate belongs to a new group of anticonvulsive drugs primarily applied in treatment of epilepsy and in preventive therapy of migraines. Topiramate is structurally unrelated to other antiepileptic drugs and acts by multiple neurostabilizing mechanisms. However, the pharmacology of topiramate appears to be complex and some of its pharmacodynamic actions still remain to be elucidated. This case report documents a fatal intoxication involving topiramate. A 41-year old woman with a known history of psychiatric disorder was found unresponsive by her husband. Resuscitation efforts did not succeed and the woman was pronounced dead at the intensive care unit four hours later. At the scene, drug packages of topiramate, citalopram and flunitrazepam were found. Autopsy including histological examination revealed morphological signs of an acute intoxication and shock. A comprehensive toxicological analysis with GC-MS was performed on the deceased's autopsy samples (femoral blood, bile, kidney, gastric content). The results revealed the presence of topiramate at a concentration of 49mg/L in the femoral blood sample, thus clearly exceeding the therapeutic range. Additionally, citalopram (0.85mg/L) and flunitrazepam in traces (<2µg/L) were detected in peripheral blood. Based on the autopsy findings and toxicological results, the cause of death was primarily attributed to an intoxication with topiramate in combination with citalopram.

Comprehensive identification of active compounds in tablets by flow-injection data-dependent tandem mass spectrometry combined with library search.

A convenient mass spectrometric approach for the identification of toxicologically relevant compounds in tablets and tablet residues is presented. For comprehensive forensic-toxicological analysis electrospray ionization mass spectrometry was accomplished in positive as well as in negative ion mode on a quadrupole-quadrupole-time-of-flight instrument. Dissolved samples were introduced into the mass spectrometer by flow-injection. Mass spectra as well as tandem mass spectra were acquired. A data-dependent acquisition strategy was used to switch between the mass spectrometric modes. Identification was accomplished via search within a tandem mass spectral library. The applied database contained 8252 spectra collected from 836 compounds in positive ion mode as well as 1023 spectra collected from 103 compounds in negative ion mode. A total of 22 casework samples collected during autopsies from mouth, oesophagus or gastric contents, seized by the police, or found with patients at hospital were screened. Twelve samples contained compounds only detectable in positive ion mode (sildenafil, dihydrocodeine, diphenhydramine, oxprenolol, N-methyl-3,4-methylenedioxyamphetamine, morphine, amphetamine, caffeine, pemoline, orphenadrine, m-chlorphenylpiperazine and tramadol), six samples contained species exclusively detectable in negative ion mode (salicylic acid, acetylsalicylic acid, ibuprofen, ketorolac, valproic acid and phenobarbital), and three samples contained diclofenac detectable in both ionization polarities. One sample did not contain any compound amenable to mass spectrometric analysis. For verification all samples were additionally analyzed by GC/MS. Both methods revealed identical results for all but one sample. The beta-adrenergic blocker oxprenolol was exclusively detected by the flow-injection method.

Challenging small human hepatocytes with opiates: further characterization of a novel prototype bioartificial liver.

Bioartificial liver (BAL) systems can take over liver functions in patients undergoing liver failure until transplantation. Recently, a novel prototype rotary BAL has been developed using small human hepatocytes (SH). This study investigated the metabolism of opiates morphine and methadone in the BAL and their influence on the basic cell culture parameters, viability, and growth of SH. Opiates may be present in patients due to pain therapy, anticancer treatment, or drug abuse. Cells were cultivated in the BAL for a total of 12 days and exposed twice to 100 microg/L of morphine or methadone. Morphine and methadone concentrations were analyzed using gas chromatography with a mass spectrometry detector. Further, the production of albumin, lactate dehydrogenase release, lactate release, urea production, and glucose consumption were measured. Cell viability and growth were determined by confocal microscopy. Cytochrome P 3A4 and uridindiphosphat (UDP) glucuronosyl transferase 2B7 in SH were analyzed by western blot. The mean cell density during treatment was 5.5 +/- 0.7 x 10(6) cells/mL (n = 6) and was not altered significantly by the opiates. Cell viability stayed above 90%. Morphine was not reduced by SH and was a stress factor as determined by decreased metabolic activity. On the other hand, SH metabolized methadone showing first-order kinetics: the first-order rate constant k = 0,019, half-life t(1/2) = 36 h. Methadone metabolism led to decreased urea and albumin production. The expression of cytochrome P 3A4, mainly responsible for methadone metabolism, was proved in SH. The prototype BAL is basically suited to support liver functions, provided patients receive therapy with methadone.

On the inter-instrument and inter-laboratory transferability of a tandem mass spectral reference library: 1. Results of an Austrian multicenter study.

The inter-instrument and inter-laboratory transferability of a tandem mass spectral reference library originally built on a quadrupole-quadrupole-time-of-flight instrument was examined. The library consisted of 3759 MS/MS spectra collected from 402 reference compounds applying several different collision-energy values for fragmentation. In the course of the multicenter study, 22 test compounds were sent to three different laboratories, where 418 tandem mass spectra were acquired using four different instruments from two manufacturers. The study covered the following types of tandem mass spectrometers: quadrupole-quadrupole-time-of-flight, quadrupole-quadrupole-linear ion trap, quadrupole-quadrupole-quadrupole, and linear ion trap-Fourier transform ion cyclotron resonance mass spectrometer. In each participating laboratory, optimized instrumental parameters were gathered solely from routinely applied workflows. No standardization procedure was applied to increase the inter-instrument comparability of MS/MS spectra. The acquired tandem mass spectra were matched against the established reference library using a sophisticated matching algorithm, which is presented in detail in a companion paper. Correct answers, meaning that the correct compound was retrieved as top hit, were obtained in 98.1% of cases. For the remaining 1.9% of spectra, the correct compound was matched at second rank. The observed high percentage of correct assignments clearly suggests that the developed mass spectral library search approach is to a large extent platform independent.

On the inter-instrument and the inter-laboratory transferability of a tandem mass spectral reference library: 2. Optimization and characterization of the search algorithm.

A sophisticated matching algorithm developed for highly efficient identity search within tandem mass spectral libraries is presented. For the optimization of the search procedure a collection of 410 tandem mass spectra corresponding to 22 compounds was used. The spectra were acquired in three different laboratories on four different instruments. The following types of tandem mass spectrometric instruments were used: quadrupole-quadrupole-time-of-flight (QqTOF), quadrupole-quadrupole-linear ion trap (QqLIT), quadrupole-quadrupole-quadrupole (QqQ), and linear ion trap-Fourier transform ion cyclotron resonance mass spectrometer (LIT-FTICR). The obtained spectra were matched to an established MS/MS-spectral library that contained 3759 MS/MS-spectra corresponding to 402 different reference compounds. All 22 test compounds were part of the library. A dynamic intensity cut-off, the search for neutral losses, and optimization of the formula used to calculate the match probability were shown to significantly enhance the performance of the presented library search approach. With the aid of these features the average number of correct assignments was increased to 98%. For statistical evaluation of the match reliability the set of fragment ion spectra was extended with 300 spectra corresponding to 100 compounds not included in the reference library. Performance was checked with the aid of receiver operating characteristic (ROC) curves. Using the magnitude of the match probability as well as the precursor ion mass as benchmarks to rate the obtained top hit, overall correct classification of a compound being included or not included in the mass spectrometric library, was obtained in more than 95% of cases clearly indicating a high predictive accuracy of the established matching procedure.

Unraveling the metabolic transformation of tetrazepam to diazepam with mass spectrometric methods.

The metabolic transformation pathways of the 1,4-benzodiazepine tetrazepam (C(16)H(17)ClN(2)O, average mass: 288.772) were studied with capillary LC-QqTOF-MS and -MS/MS by analyzing human plasma and urine samples collected from healthy volunteers. Each volunteer took 50 mg of tetrazepam, given in the form of one tablet of Myolastan (Sanofi-Synthelabo, Vienna, Austria). Accurate molecular mass measurements in full-scan mode (scan range: 50-700) were used to survey the collected samples for putative metabolic transformation products. Full-scan fragment ion mass spectra were collected in subsequent LC/MS/MS experiments. Each spectrum was matched to a spectral library containing 3759 MS/MS-spectra of 402 compounds, including eighteen different benzodiazepines, to prove the structural relatedness of a tentative metabolite to tetrazepam. This "similarity search" approach provided a rapid and powerful tool to exclude non-drug-related species, even without any knowledge of the fragmentation chemistry. Interpretation of tandem mass spectrometric data was only required in order to elucidate the site of transformation. Using this strategy, 11 major classes of tetrazepam metabolites were identified. Possible metabolic routes from tetrazepam to diazepam (C(16)H(13)ClN(2)O, average mass: 284.740) via repeated hydroxylation and dehydration of the cylohexenyl moiety were discovered. No evidence for extensive hydroxylation of tetrazepam at position 3 of the diazepine ring was found. In contrast to what is commonly believed, this distinct transformation reaction may be of only minor importance. Furthermore, the occurrence of demethylation, hydration, and glucuronidation reactions was proven.

Small human hepatocytes in rotary culture for treatment of alcohol addicts? A pilot study.

BACKGROUND: Current approaches to support alcohol addict and/or benzodiazepine-treated patients with liver failure include culturing human cells to take over basic metabolic functions for a certain time. METHODS: Small human hepatocytes (SH) were grown in a rotary cell culture system, and their potential to metabolize alcohol and the benzodiazepines oxazepam and diazepam was evaluated. Control experiments were performed with SV40-immortalized HEP cells and cell respective drug-free media. RESULTS: Our results show that SH in rotary culture are able to metabolize ethanol in reasonable amounts compared with evaporation controls (p<0.01). Moreover, SH are also able to metabolize oxazepam and diazepam which proves their ability to perform conjugation and the presence of functional cytochrome P450 enzymes. Basic metabolic activities such as glucose consumption, albumin and urea production are not significantly influenced by the drugs used, which is a precondition for clinical use of these cells. Significantly increased lactate dehydrogenase release indicates enhanced cell death in cultures of SH incubated with either ethanol (p<0.05) or diazepam (p<0.005), but stable viability at or above 90% suggests that cell proliferation is able to keep up with drug-induced cell death. CONCLUSION: Our preliminary study provides evidence that SH are basically suited to support alcohol-abusing and/or benzodiazepine-treated patients undergoing liver failure.

Another 'soberade' on the market: does Outox keep its promise?

OBJECTIVE: Several products are being widely promoted for reduction of the concentration of alcohol in the human body. One of these preparations, the fructose soft drink Outox, claims to noticeably increase the alcohol elimination rate (beta 60). Theories to explain this 'fructose effect' are based on the assumption that NAD+, the coenzyme for alcohol dehydrogenase, is regenerated faster in the presence of fructose. METHOD: A randomized double-blind, placebo-controlled cross-over study was performed with 30 volunteers in two drinking sessions each. Under strictly identical conditions, the same amount of alcohol was consumed, followed by the consumption of either 250 ml Outox or 250 ml placebo. Periodical measurements of blood (BAC), breath (BrAC) and urine alcohol concentration (UAC) were performed. RESULTS: Analyses revealed a significant difference (P<0.0001) between the mean alcohol levels of the Outox and the placebo drinking sessions. The overall mean BAC difference was 0.077 g/l (BAC 0.748 g/l without vs 0.671 g/l with Outox), equivalent to 10.3%. The mean BrAC difference was 0.045 mg/l (BrAC 0.314 mg/l without vs 0.269 mg/l with Outox), equivalent to 14.3%. Differences were lower for women than for men. A significant difference between the alcohol elimination rates (beta 60) was not found. CONCLUSIONS: The results show that the soft drink Outox may decrease the alcohol concentration by about 10%. However, BAC and BrAC differences are rather a consequence of slower gastric absorption of alcohol, because Outox does not increase the alcohol elimination rate. Our study demonstrates that the claim of Outox or other fructose drinks to work as a 'soberade' cannot be proven from a scientific point of view. It should be the task of physicians to warn potential consumers, especially in connection with drinking and driving.

Elimination rates of breath alcohol.

Legal driving limits are set coequally with 0.5 g/L blood alcohol concentration (BAC) or 0.25 mg/L breath alcohol concentration (BrAC) in Austria as well as in other European countries. As mostly some time elapses between BrAC measurement and driving offence, a back calculation of alcohol concentrations is often required. The calculation of hourly BrAC elimination rates can thereby help to avoid unnecessary variances. A study with 59 participants was performed under social conditions. BrAC was determined with the legally accredited Alcotest 7110 MK III A every 30 min, and concomitantly venous blood samples were drawn. Five hundred and four BrAC/BAC value pairs were evaluated. The overall mean peak BrAC was calculated with 0.456 mg/L (+/-0.119 mg/L standard deviation). The mean hourly BrAC elimination rate was overall determined with 0.082 mg/L per h (0.050-0.114, 95% range). Mean rate of females (0.087 mg/L h(-1)) and the according 95% limits were statistically significantly higher than of males (mean rate 0.078 mg/L h(-1), p<0.04). Our results confirm the possibility to implement hourly BrAC elimination rates, provided that adequate statistical ranges and basic forensic scientific rules that have been set up for alcohol back calculations are observed.

Medicolegal aspects of tetrazepam metabolism.

The benzodiazepine tetrazepam is primarily muscle relaxant with comparably lower central sedating effects and is therefore commonly prescribed for muscle spasms of different origins. To evaluate tetrazepam metabolism, a study was conducted with ten healthy volunteers. Blood and urine samples were regularly collected after the intake of 50 mg tetrazepam. Toxicological analyses revealed that tetrazepam is also metabolized to diazepam and further to nordazepam, which has not yet been reported. Tetrazepam and diazepam could be detected in urine samples at least 72 h after intake, the diazepam concentration being 33% (+/-14% SD), on average, of the tetrazepam concentration. On the basis of three case histories, the importance of the detection of these newly described metabolites is shown as necessary to prevent false accusations and potential negative legal consequences for examined persons.

An announced suicide with ecstasy.

Most cases of ecstasy overdose turn out to be accidental, whereas suicide attempts with designer drugs occur only sporadically. We report an announced suicide by means of a combination of 3,4-methylenedioxymethamphetamine (MDMA) and 3,4-methylenedioxyethylamphetamine (MDEA). During autopsy, sampling for toxicological investigation (peripheral blood, urine, cerebrospinal fluid, bile and gastric contents) occurred. Serum concentrations as high as 13.33 mg/l for MDMA, 7.32 mg/l for MDEA and 0.43 mg/l for 3,4-methylenedioxyamphetamine were found. Ecstasy tablets, which were confiscated by the police a few days earlier, showed also a combination of MDMA and MDEA. This fact suggests that the ingested tablets probably came from the same source as the seized pills.

Combined use of ESI-QqTOF-MS and ESI-QqTOF-MS/MS with mass-spectral library search for qualitative analysis of drugs.

The potential of the combined use of ESI-QqTOF-MS and ESI-QqTOF-MS/MS with mass-spectral library search for the identification of therapeutic and illicit drugs has been evaluated. Reserpine was used for standardizing experimental conditions and for characterization of the performance of the applied mass spectrometric system. Experiments revealed that because of the mass accuracy, the stability of calibration, and the reproducibility of fragmentation, the QqTOF mass spectrometer is an appropriate platform for establishment of a tandem-mass-spectral library. Three-hundred and nineteen substances were used as reference samples to build the spectral library. For each reference compound, product-ion spectra were acquired at ten different collision-energy values between 5 eV and 50 eV. For identification of unknown compounds, a library search algorithm was developed. The closeness of matching between a measured product-ion spectrum and a spectrum stored in the library was characterized by a value called "match probability", which took into account the number of matched fragment ions, the number of fragment ions observed in the two spectra, and the sum of the intensity differences calculated for matching fragments. A large value for the match probability indicated a close match between the measured and the reference spectrum. A unique feature of the library search algorithm-an implemented spectral purification option-enables characterization of multi-contributor fragment-ion spectra. With the aid of this software feature, substances comprising only 1.0% of the total amount of binary mixtures were unequivocally assigned, in addition to the isobaric main contributors. The spectral library was successfully applied to the characterization of 39 forensic casework samples.

Ecstasy--deadly risk even outside rave parties.

Fatalities due to 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") are rare in Austria, although the use of designer drugs has become quite common. This is the first published case of a fatal MDMA intoxication in Austria. A 19-year-old girl died after the consumption of ecstasy tablets in the apartment of a friend. Blood analysis gave a concentration of MDMA as 3.8 mg/L and traces of its metabolite MDA. Cannabinoids were found as well. This case shows that the consumption of MDMA, without physical stress, can lead to death.