Withdrawn: Hair Analysis for Drug-Facilitated Crime: The Critical Role of Hair Growth Rate.

Hair analysis is increasingly used in detecting drug-facilitated crime (DFC) claiming success in identifying even single dose exposures. The calculation of accurate deposition time of the drug in hair is typically based on the assumption of mean hair growth of 1 cm/month. We describe a case of potential exposure to flunitrazepam. Assuming the literature average hair growth rate of 1 cm/month, the alleged victim had measurable amounts of the 7 amino flunitrazepam a month after the alleged drug exposure. However, in this case, due to hair dying, the true growth rate could be quantified at 1.5 cm/month. This difference has led to different interpretation from the one based on the average assumed hair growth of 1 cm/month. In conclusion, hair growth rate can be a critical variable in verifying the alleged time of drug exposure.

Simultaneous quantification of EVT201, a novel partial positive allosteric GABAA receptor modulator, and its two metabolites in human plasma by UHPLC/MS/MS.

A sensitive, accurate and rapid UHPLC-MS/MS method was developed and validated for the simultaneous determination of EVT201 and its two metabolites, Ro46-1927 and Ro18-5528, in human plasma. D6-EVT201 was used as the internal standard (IS). Plasma samples were extracted using ethyl acetate after being alkalized with saturated sodium carbonate solution. Chromatographic separation was carried out on an Acquity BEH C18 column (2.1 × 50 mm, 1.7 µm) with a gradient mobile phase at a flow-rate of 0.50 mL/min. The analytical run time was 5.5 min. For mass spectrometric detection, multiple reaction monitoring (MRM) was used. The MRM ion transitions were m/z 373.2 → 58.0 for EVT201, m/z 359.2 → 316.1 for Ro46-1927, m/z 291.2 → 274.1 for Ro18-5528 and m/z 379.3 → 64.0 for the IS. The linear range was 0.2-200 ng/mL for each analyte, with a correlation coefficient (r) over 0.9900. The intra-/inter- precision was within 7.9% and 4.5% for EVT201, 13.2% and 6.3% for Ro46-1927, 3.7% and 4.1% for Ro18-5528. For the accuracy, the relative bias of intra-/inter- run was no more than 6.4% and 4.6% for EVT201, 9.4% and 7.9% for Ro46-1927, -6.9% and -7.5% for Ro18-5528. The validated method was successfully applied to the analysis of more than 1500 samples from a Phase I clinical trial. The incurred sample reanalysis (ISR) of 146 samples from the study was evaluated and the results met the acceptance criteria. It indicated that the method could be used for the pharmacokinetic study of EVT201.

Potential impact of drug effects, availability, pharmacokinetics, and screening on estimates of drugs implicated in cases of assault.

Drug-facilitated sexual assault (DFSA) is a serious and troubling crime. It is important to know if and how different drugs might be used to facilitate assault in order to deter such crime. There are a number of ways in which drugs that are used for DFSA might not be detected by routine screens. The purpose of this analysis was to draw reasonable inferences regarding drugs with a high likelihood of being used for DFSA and not being detected by routine screens. National data from poison control centres, hospital emergency rooms, and law enforcement seizures were used to evaluate the relative magnitude of problems and illicit availability associated with different classes of drugs. General drug classes were examined to include additional drugs that might be used for DFSA on the basis of their amnesic effects, widespread availability, and pharmacokinetics (i.e. short half-life). The benzodiazepine-site ligands zolpidem and eszopiclone, 'club drugs' GHB and ketamine, muscle relaxants such as carisoprodol, and antihistamines such as diphenhydramine were identified as drugs that might be used for DFSA and remain undetected by routine screens. Future studies that are designed to examine the role of these drugs in DFSA cases could provide better estimates of their use for DFSA. A better understanding of what is being missed in DFSA cases might help prioritize the development of new assays, provide rationale for the availability of particular assays for routine testing, and inform practitioners and the general public of the potential DFSA risks of certain drugs.

Comparison of clonazepam compliance by measurement of urinary concentration by immunoassay and LC-MS/MS in pain management population.

BACKGROUND: Physicians determine patient compliance with their medications by use of urine drug testing. It is known that measurement of benzodiazepines is limited by immunoassay specificity and cutoff limits and therefore does not offer physicians an accurate picture of their patients' compliance with these medications. A few studies have used lower cutoffs to demonstrate patient compliance. OBJECTIVES: To define more appropriate cutoffs for compliance monitoring of patients prescribed clonazepam as determined using immunoassay and liquid chromatography-tandem mass spectrometry (LC-MS/MS). STUDY DESIGN: A diagnostic accuracy study of the urinary excretion of clonazepam. METHODS: Millennium Laboratories performed measurements on the urinary excretion of pain patients prescribed clonazepam as the indicator test. This benzodiazepine was chosen because it forms one major metabolite, 7-aminoclonazepam which is specific for that drug. Patients whose only benzodiazepine medication was clonazepam were selected as the test population. The Millennium Laboratories test database was filtered first to select patients on clonazepam, then a second filter was used to eliminate patients with any other listed benzodiazepine medications. Samples were tested using the Microgenics DRI benzodiazepine assay with a 200 ng/mL cutoff. The same samples were quantitatively assessed for 7-aminoclonazepam by LC-MS/MS with a cutoff of 40 ng/mL. The results from the immunoassay were scored as positive or negative while the quantitative results from the LC-MS/MS were also scored as positive or negative depending upon their concentration. RESULTS: Samples from 180 patients met these medication criteria. The positivity rates were 21% (38 samples) by immunoassay. The positivity rate was 70% (126 samples) if the LC-MS/MS cutoff was set at 200 ng/mL. However, the positivity rate was 87% (157 samples) if the LC-MS/MS was set at 40 ng/mL. Concentration distributions revealed a significant fraction (7%) in the 40 - 100 ng/mL range. LIMITATIONS: A limitation of the study was the inability to measure lower than 40 ng/mL. There may be another fraction of the population that was positive below the cutoff value. CONCLUSIONS: The difference in positivity rate between the immunoassay and the LC-MS/MS result showed that the nominal 200 ng/mL cutoff of the immunoassay did not apply to 7-aminoclonazepam. This low immunoassay positivity rate is inconsistent with the manufacturer's published cross reactivity data for clonazepam and 7-aminoclonazepam. These data illustrate the limitations of using a 200 ng/mL cutoff to monitor clonazepam compliance and suggest that a cutoff of 40 ng/mL or less is needed to reliably monitor use of this drug.

Determination of bromazepam, clonazepam and metabolites after a single intake in urine and hair by LC-MS/MS. Application to forensic cases of drug facilitated crimes.

The number of reports on drug facilitated crimes is increasing these last years. Apart from ethanol and cannabis, benzodiazepines (BZD) and analogs are the most common drugs reported to be used probably due to their amnesic and sedative properties. We have developed a rapid and sensitive method using LC-MS/MS triple stage quadrupole (TSQ) for the determination of single exposure to bromazepam (Lexomil, 6 mg) and clonazepam (Rivotril, 2 mg) in urine and hair of healthy volunteers. Chromatography was carried out on a Uptisphere ODB 5 microm, 2.1 mm x 150 mm column (Interchim) with a gradient of acetonitrile and formate 2 mM buffer, pH 3. Urine was extracted with Toxitube A (Varian) and allowed the detection of bromazepam, 3-hydroxy-bromazepam, clonazepam and 7-Aminoclonazepam for more than 6 days. Head hair, collected 1 month after the exposure, was treated by incubation with Soerensen buffer pH 7.6, followed by liquid-liquid extraction with dichloromethane for common BZD. A specific pre-treatment for amino-BZD, with an incubation of 15 min at 95 degrees C in 0.1 N NaOH before liquid-liquid extraction with dichloromethane, gave better recoveries and repeatability. After single exposure, bromazepam was present in powdered hair at 28 pg/mg and 7-Aminoclonazepam at 22 pg/mg in the first 1-cm segment, while no clonazepam was detectable. This method was applied in two forensic cases. It allowed us to determine bromazepam in urine 3 days after the alleged offense and in cut head hair at a concentration of 6.7 pg/mg only in the 2-cm proximal segment. The other case showed the presence of clonazepam and 7-Aminoclonazepam in urine a few hours after the offense and the presence of 7-Aminoclonazepam at about 3.2 pg/mg in axillary hair 4 months later.

Gamma-hydroxybutyrate: bridging the clinical-analytical gap.

Laboratory detection of gamma-hydroxybutyrate (GHB) has been published as early as the 1960s. However, wide-scale use of GHB during the 1990s has led to the development of current analytic methods to test for GHB and related compounds. Detection of GHB and related compounds can be clinically useful in confirming the cause of coma in an overdose patient, determining its potential role in a postmortem victim, as well as evaluating its use in a drug-facilitated sexual assault victim. Analytical method sensitivity must be known in order to determine the usefulness and clinical application. Most laboratory cut-off levels are based on instrument sensitivity and will not establish endogenous versus exogenous GHB levels. Interpretation of GHB levels must include a knowledge base of endogenous GHB, metabolism of GHB and related compounds, as well as postmortem generation. Due to potential analytical limitations in various GHB methods, it is clinically relevant to specifically request for GHB as well as related GHB compounds if they are also in question. Various storage conditions (collection time, types of containers, use of preservatives, storage temperature) can also affect the analysis and interpretation of GHB and related compounds.

Endogenous diazepam concentrations in the serum of patients with liver neoplasms.

The study included 61 patients (35 men and 26 women) ages 47 to 74 in whom a primary liver cancer was diagnosed or neoplastic metastases to the liver were confirmed in the course of a cancer of the stomach or the large bowel. In each patient the endogenous serum diazepam concentration (ESDC) was estimated chromatographically and the results obtained were compared to selected clinical traits such as the magnitude and number of neoplastic changes and their location in the liver parenchyma, the histological form of the tumor and the primary location of the cancer in the case of neoplasms of the alimentary canal. The determination of the ESDC was also carried out in a control group made up of voluntary blood donors. Neither group examined received any medication belonging to the benzodiazepine group. From the results of the tests conducted it was confirmed that the average ESDC of patients with liver neoplasms was 65 times higher than that of the control group. Simultaneously, however, in patients with a primary liver cancer the average endogenous concentration was higher than in patients with neoplastic metastases to that organ and this was statistically significant. The location in the hepatic parenchyma of the neoplastic change as well as the primary location of the cancer remained without a statistically significant influence in the changes of ESDC. It was moreover shown that significantly high ESDC were associated in the liver mainly with increased neoplastic growth (above 3 cm in diameter) and with multiple spread (5 focuses and more).

Stability of nitrobenzodiazepines in postmortem blood.

Studies were undertaken to determine the stability of nitrobenzodiazepines and their 7-amino metabolites in water and blood. At 22 degrees C nitrazepam and clonazepam were stable in sterile fresh blood containing preservative over 28 days, whereas 25% of flunitrazepam was degraded. At 37 degrees C all three drugs were substantially lost over 9 h (29-51%). There was only a small loss observed for the 7-amino metabolites and no substantial amounts of parent drug and 7-amino metabolite were degraded in water under these conditions. In the absence of preservative substantial amounts (25-50%) of parent drugs were lost in fresh blood over 10 days at 22 degrees C. In bacterially-contaminated postmortem blood all three drugs were completely degraded over 8 h at 22 degrees C with almost all drug completely converted to the respective 7-amino metabolite. These metabolites were also partially degraded (10-20%) over 45 h at 22 degrees C. All 3 nitrobenzodiazepines were stable in blood stored for up to 24 months at -20 degrees C, or 4 degrees C over 10 months. Their respective 7-amino metabolites were, however, relatively unstable at -20 degrees C with a significant loss (29%) after 2 months. At 4 degrees C a 21% loss occurred after 1 month. Freeze/thawing was found not to affect the concentration of nitrobenzodiazepine and 7-amino metabolites. These results show that the nitrobenzodiazepines and their metabolites are unstable chemically and metabolically in blood. We advise that blood collected for the purpose of nitrobenzodiazepine determinations should be preserved with sodium fluoride, stored at -20 degrees C and assayed as soon as practicable, preferably within a week of collection.

Postmortem distribution and redistribution of nitrobenzodiazepines in man.

The distribution of the nitrobenzodiazepines, flunitrazepam, clonazepam and nitrazepam, and their respective 7-amino metabolites were examined in blood, serum, vitreous humor, liver, bile and urine of decedents taking these drugs. Peripheral blood, serum and liver concentrations were not significantly different to each other. However, vitreous concentrations were one-third of blood, while bile concentrations were 5-12 fold higher. Blood, serum and vitreous contained predominantly the 7-amino metabolite, liver contained only the metabolite, while bile contained significant concentrations of both the parent drug and the 7-amino metabolite. Urine contained only small concentrations of parent drug, however, as expected a number of metabolites were detected. Redistribution studies compared the drug concentrations of femoral blood, taken at body admission to the mortuary, with femoral blood taken at autopsy approximately 39 h later in 48 cases. The concentrations of 7-amino metabolites were not significantly different, however the concentrations of parent nitrobenzodiazepines were significantly higher in the admission specimens. In 6 cases in which subclavian blood was taken, the concentrations were not significantly different to the concentrations in admission blood. Similar findings were observed when femoral and subclavian blood concentrations were compared in 6 cases. There was also no apparent difference in total blood concentrations of nitrobenzodiazepines when blood concentrations taken in hospital shortly prior to death were compared to postmortem blood. Postmortem diffusion into peripheral blood is therefore not a confounding factor in the interpretation of nitrobenzodiazepine concentrations.

Testing human hair for flunitrazepam and 7-amino-flunitrazepam by GC/MS-NCI.

To validate information on flunitrazepam use, we investigated human hair for flunitrazepam and its major metabolite 7-amino-flunitrazepam by gas chromatography coupled to mass spectrometry in negative chemical ionization mode of detection. Samples were twice decontaminated with methylene chloride, pulverized in a ball mill and 50 mg of powdered hair were incubated in Soerensen buffer (pH 7.6) in the presence of diazepam-d5 used as internal standard. After liquid-liquid extraction of the incubation medium with diethylether-chloroform (80:20, by vol.), the organic phase was evaporated and the dry extract was derivatizated with heptafluorobutyric anhydride. Benzodiazepines were separated on a 30 m capillary column and detected using single ion monitoring. Among 40 hair samples tested (obtained from drug addicts deceased by heroin overdose), 14 were positive for both flunitrazepam and 7-amino-flunitrazepam and 12 for 7-amino-flunitrazepam only. Concentrations ranged from 31 to 129 pg/mg (mean: 60 pg/mg) and from 3 to 161 pg/mg (mean: 46 pg/mg) for flunitrazepam (14 cases) and 7-amino-flunitrazepam (26 cases), respectively. This first report described the detection of flunitrazepam and 7-amino-flunitrazepam in hair of chronic abusers. Due to the low concentrations observed, negative chemical ionization appears to be the alternative to test flunitrazepam and other benzodiazepines in hair.

Sleeping time after phenobarbital treatment and the brain levels of gamma-aminobutyric acid and phenobarbital at the regaining of righting response point in ethionine-induced liver-disordered mice.

The mechanism of prolongation of sleeping (anesthesia) time after phenobarbital (PB) treatment was assessed in mice with ethionine (ET)-induced liver disorders (ET-treated group). The brain gamma-aminobutyric acid (GABA), glutamic acid (GLU), lactic acid (LA), and pyruvic acid (PA) levels were significantly higher in the ET-treated group than the control group. The ET-treated group showed an abnormal neurotransmission and a decrease in energy metabolism. After administration of PB (175 mg/kg, i.p.), sleeping time and the brain GABA, GLU, LA, PA, and PB levels at the awakening point were compared between ET-treated and control groups. Sleeping time in the ET-treated group was two times longer than that in the control group. At the awakening point, the brain GABA and LA levels in the ET-treated and control groups and the PA level in the ET-treated group were significantly lower than those without PB treatment; and the GLU level in the ET-treated group was significantly higher than that without PB treatment. The brain concentrations of PB in both groups remained the same for seven hr after PB treatment. There was no difference in the brain PB concentration between the two groups at the awakening point, although the ET-treated group showed impairment of excretion of PB at 18 hr of PB treatment. In conclusion, awakening is not directly correlated with a decrease in PB in the brain, but rather to changes in the brain GABA, GLU, and other substances, and an inhibition of the neurotransmission and decreased energy metabolism in the brain are considered to be involved in the prolongation of PB-induced sleeping time in the ET-treated mice.