Microsampling with cotton thread: Storage and ultra-sensitive analysis by thread spray mass Spectrometry

Storage and quantitative analysis of small volumes of biofluids are challenging, especially when low concentrations of analytes are to be detected in the presence of complex matrices. In this study, we describe an integrated thread-based approach for stabilizing small blood volumes in the dry-state at room temperature, while also offering direct analysis capabilities via thread spray mass spectrometry. The analytical merits of this novel microsampling platform was demonstrated via the direct analysis of diazepam and cocaine in dried blood samples stored for 42 days. In-situ in-capillary blood processing from hydrophobic threads enabled limits of detection as low as parts-per-quadrillion to be reached. We validated this ultra-sensitivity by analyzing small tissue-like residues collected after pushing a thread through the sample once. The implications of this sample collection, storage, and analysis platform can be extensive with direct applications in forensics and clinical studies.

A complicated case of bowel obstruction with sepsis and methamphetamine toxicity in a child with pica

In this report, a pediatric case of bowel obstruction with sepsis complicated by methamphetamine toxicity is described. The decedent, an eleven-year-old female with a clinical history of pica, was found unresponsive in her home and pronounced dead following unsuccessful resuscitative efforts. Radiologic imaging showed multiple radio-opaque foreign objects in the stomach and bowel. Autopsy revealed a green leafy substance, coins and other metallic items, folded paper, and plastic in her stomach and bowels. Postmortem iliac blood and urine tested positive for amphetamine and methamphetamine. While the decedent's medical history and autopsy findings provided evidence consistent with bowel obstruction with sepsis due to the ingestion of foreign materials, the high methamphetamine concentration was suggestive of concurrent methamphetamine toxicity. Unique complications associated with this case include the phenomenon that methamphetamine toxicity and bowel obstruction can present similarly in children and the reported opinion that accidental drug ingestion is uncommon in children over the age of five. This case emphasizes that the age range for suspected accidental drug ingestion should be expanded for those with pica, as these patients, despite being older, may not be able to differentiate between what they should and should not ingest. Furthermore, when treating a pediatric patient with pica that appears to present with bowel obstruction, unintentional drug ingestion should also be considered, particularly if there is a suspicion that the child lives in a household where drugs are abused, given the prospect that drug toxicity can present similarly.

Novel Selectivity-Based Forensic Toxicological Validation of a Paper Spray Mass Spectrometry Method for the Quantitative Determination of Eight Amphetamines in Whole Blood

Paper spray tandem mass spectrometry is used to identify and quantify eight individual amphetamines in whole blood in 1.3 min. The method has been optimized and fully validated according to forensic toxicology guidelines, for the quantification of amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxy-N-methylamphetamine (MDMA), 3,4-methylenedioxy-N-ethylamphetamine (MDEA), para-methoxyamphetamine (PMA), para-methoxymethamphetamine (PMMA), and 4-fluoroamphetamine (4-FA). Additionally, a new concept of intrinsic and application-based selectivity is discussed, featuring increased confidence in the power to discriminate the amphetamines from other chemically similar compounds when applying an ambient mass spectrometric method without chromatographic separation. Accuracy was within ±15% and average precision was better than 15%, and better than 20% at the LLOQ. Detection limits between 15 and 50 ng/mL were obtained using only 12 μL of whole blood. Graphical abstract ᅟ.

Prevalence and concentrations of drugs in older suspected drugged drivers

OBJECTIVE

Older drivers are somewhat more likely to be involved in car crashes than middle-aged drivers but less likely to be involved than younger drivers. This study aimed to assess the extent of drug use in older suspected drunk and drugged drivers, with respect to which drugs were detected and at which concentrations.

METHODS

Blood samples from older suspected drunk and drugged drivers taken between February 1, 2012, and May 22, 2013, were identified from the database at the Norwegian Institute of Public Health and were retrospectively analyzed for a broad repertoire of drugs relevant for impairment. The prevalence of different drugs among the suspected drunk and drugged drivers was studied. Regarding drug concentrations, the findings in older drivers (>65 years) were compared to a reference group of apprehended drivers aged 20-40 years.

RESULTS

Four hundred and ten older suspected drunk and drugged drivers were included. Any drug (including ethanol) was detected in 92% of blood samples, and ethanol was detected in 81%. Benzodiazepines were found in 15% of the older drivers and z-hypnotics (zopiclone or zolpidem) were detected in 13%. The most frequent single legal drugs found in blood samples taken from older impaired drivers were zopiclone (9.8%) and diazepam (9.3%). Regarding drug combinations, older drivers used a mean number of 1.4 drugs, and 20% of ethanol-positive cases showed at least one other drug. High drug concentrations of clonazepam and diazepam were more frequently seen in the younger group.

CONCLUSIONS

This study showed that drugs were detected in the vast majority of older drivers suspected for drunk or drugged driving. Ethanol was the most frequent drug detected, followed by zopiclone and diazepam. Older drivers combine drugs to a lesser degree than younger drivers, but their combination of ethanol and other drugs represents a considerable traffic risk. Lower concentrations of benzodiazepines are seen in older compared to younger drivers.

Lisdexamfetamine Dimesylate: Prodrug Delivery, Amphetamine Exposure and Duration of Efficacy

Lisdexamfetamine dimesylate (LDX) is a long-acting d-amphetamine prodrug used to treat attention-deficit/hyperactivity disorder (ADHD) in children, adolescents and adults. LDX is hydrolysed in the blood to yield d-amphetamine, and the pharmacokinetic profile of d-amphetamine following oral administration of LDX has a lower maximum plasma concentration (C_max), extended time to C_max (T_max) and lower inter- and intra-individual variability in exposure compared with the pharmacokinetic profile of an equivalent dose of immediate-release (IR) d-amphetamine. The therapeutic action of LDX extends to at least 13 h post-dose in children and 14 h post-dose in adults, longer than that reported for any other long-acting formulation. Drug-liking scores for LDX are lower than for an equivalent dose of IR d-amphetamine, which may result from the reduced euphorigenic potential associated with its pharmacokinetic profile. These pharmacokinetic and pharmacodynamic characteristics of LDX may be beneficial in the management of symptoms in children, adolescents and adults with ADHD.

[Triage DOA screening in a case of methamphetamine and its analogue poisoning]

CASE REPORT

A 20-year-old woman presented with the chest pain, nausea, respiratory strange feeling, and a large quantity of sweating. On the stimulant zone of 8 groups of drugs of Triage DOA screening it showed an equivocal positivity while all of the other zones gave negative results. She denied taking drugs. No injection scar was found. And she was then hospitalized because little was known about her symptoms. When the unconscious patient was discovered at rest room inside hospital the next day, she was transferred to emergency and critical care center. In the same screening test positivity on the stimulant zone was observed, and furthermore both amphetamine and methamphetamine were detected by GCMS analysis. For 4 days positivity on the stimulant zone lasted. From the fact of disturbance of consciousness, restlessness, excitation and tachycardia, respiration disorder, and the pupil dilatation drug poisoning was deeply suspected.

DISCUSSION

While the stimulant zone of Triage DOA showed the equivocal positivity when 7 hours has elapsed until she became aware of abnormality and hospitalized, in the same screening of 30 hours later positivity was verified clearly. Several problems derived from the detection method, pharmacokinetic factors and pharmacodynamic aspect were discussed as for the difference of the results detected.

Forensic toxicology findings in deaths involving gamma-hydroxybutyrate

Concentrations of the illicit drug gamma-hydroxybutyrate (GHB) were determined in femoral venous blood and urine obtained at autopsy in a series of GHB-related deaths (N = 49). The analysis of GHB was done by gas chromatography after conversion to gamma-butyrolactone and quantitation of the latter with a flame ionization detector. The cutoff concentration of GHB in femoral blood or urine for reporting positive results was 30 mg/L. The deceased were mainly young men (86%) aged 26.5 +/- 7.2 years (mean +/- SD), and the women (14%) were about 5 years younger at 21.4 +/- 5.0 years. The mean, median, and highest concentrations of GHB in femoral blood (N = 37) were 294, 190, and 2,200 mg/L, respectively. The mean urine-to-blood ratio of GHB was 8.8, and the median was 5.2 (N = 28). In 12 cases, the concentrations of GHB in blood were negative (<30 mg/L) when the urine contained 350 mg/L on average (range 31-1,100 mg/L). Considerable poly-drug use was evident in these GHB-related deaths: ethanol (18 cases), amphetamine (12 cases), and various prescription medications (benzodizepines, opiates, and antidepressants) in other cases. Interpreting the concentrations of GHB in postmortem blood is complicated because of concomitant use of other psychoactive substances, variable degree of tolerance to centrally acting drugs, and the lack of reliable information about survival time after use of the drug.

Capillary electrophoresis with laser-induced fluorescence and pre-column derivatization for the analysis of illicit drugs

In the current paper, we report the development of a new capillary electrophoresis method using pre-column derivatization and laser-induced fluorescence detection for the determination of ephedrine and amphetamine drugs. Our new method allows for the identification and quantification of six commonly used illicit drugs namely pseudoephedrine, ephedrine, amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine, and 3,4-methylenedioxymethylamphetamine, respectively, as well as propafenone (internal standard). Following derivatization with fluorescein isothiocyanate, a total of six amphetamine drugs and the internal standard could readily be separated using a fused-silica 75 micromID x 60 cm length (effective length: 50.2 cm) capillary column. The mobile phase consisted of buffer containing 20mM borate (pH 12, adjusted with sodium hydroxide). Samples were injected in pressure mode with the capillary being operated at 25kV/25 degrees C, and the detection of the derivatized compounds was sought using a laser-induced fluorescence (LIF) detector (lambda(ex)=488 nm and lambda(em)=520 nm), with a run-time of 20 min. The current method was validated with regard to precision (relative standard deviation, RSD), accuracy, sensitivity, linear range, limit of detection (LOD) and limit of quantification (LOQ). In human blood and urine samples, detection limits were 0.2 ngmL(-1), and the linear range of the calibration curves was 0.5-100 ngmL(-1). The intra-day and inter-day precisions were both less than 13.22%.

Pipette tip solid-phase extraction and gas chromatography – mass spectrometry for the determination of methamphetamine and amphetamine in human whole blood

Methamphetamine and amphetamine were extracted from human whole blood samples using pipette tip solid-phase extraction (SPE) with MonoTip C(18) tips, on which C(18)-bonded monolithic silica gel was fixed. Human whole blood (0.1 mL) containing methamphetamine and amphetamine, with N-methylbenzylamine as an internal standard, was mixed with 0.4 mL of distilled water and 50 microL of 5 M sodium hydroxide solution. After centrifugation, the supernatant was extracted to the C(18) phase of the tip (pipette tip volume, 200 microL) by 25 repeated aspirating/dispensing cycles using a manual micropipettor. Analytes retained in the C(18) phase were eluted with methanol by five repeated aspirating/dispensing cycles. After derivatization with trifluoroacetic anhydride, analytes were measured by gas chromatography - mass spectrometry with selected ion monitoring in the positive-ion electron impact mode. Recoveries of methamphetamine and amphetamine spiked into whole blood were more than 87.6 and 81.7%, respectively. Regression equations for methamphetamine and amphetamine showed excellent linearity in the range of 0.5-100 ng/0.1 mL. The limits of detection for methamphetamine and amphetamine were 0.15 and 0.11 ng/0.1 mL, respectively. Intra- and interday coefficients of variation for both stimulants were not greater than 9.6 and 13.8%, respectively. The determination of methamphetamine and amphetamine in autopsy whole blood samples is presented, and was shown to validate the present methodology.

Age- and gender-related differences in blood amphetamine concentrations in apprehended drivers: lack of association with clinical evidence of impairment

BACKGROUND

New legislation aimed at combating driving under the influence of drugs (DUID) in Sweden stipulated zero-concentrations in blood for scheduled substances. DUID suspects (n = 300), with amphetamine as the only psychoactive drug identified in blood, were investigated in relation to age and gender. In a smaller retrospective sample (n = 70) the relationship between clinical tests of impairment were compared with the concentration of amphetamine in blood.

MEASUREMENTS

All forensic blood samples were subjected to a broad toxicological screening analysis by immunoassay methods [enzyme multiplied immunoassay technique/cloned enzyme donor immunoassay (EMIT/CEDIA)] and positive results were verified by gas chromatography-mass spectrometry (GC-MS). The limit of quantitation (LOQ) for determination of amphetamine in blood was 0.03 mg/l. People suspected of being under the influence of drugs were examined by a physician who asked various questions about state of health and use of drugs and also administered simple psychomotor and cognitive tests of impairment. After conducting these tests the physician concluded whether the suspects were not impaired, slightly, moderately or highly impaired by drugs other than alcohol.

FINDINGS

Among 300 DUID suspects with amphetamine in blood there were 246 men (82%) and 54 women (18%). Mean age (+/- SD) of the men was 37.1 +/- 8.7 years compared with 35.5 +/- 7.1 years for the women (P > 0.05). The frequency distribution of blood amphetamine concentration was positively skewed with mean, median and highest values of 1.0 mg/l, 0.9 mg/l and 7.1 mg/l, respectively. The mean concentrations were slightly higher in the women 1.11 mg/l (median 1.0 mg/l) compared with 0.97 mg/l (median 0.8 mg/l) in the men (P > 0.05). There was a weak but statistically significant correlation between the person's age and the concentration of amphetamine in blood (r = 0.18, P < 0.05). The results of clinical tests of impairment showed no relationship with the concentration of amphetamine in blood according to analysis of variance (P > 0.05).

CONCLUSIONS

The lack of association between degree of drug influence and the concentration of amphetamine in blood speaks against the notion of introducing concentration per se limits or graded penalties depending on the blood-concentration of this stimulant. Zero-concentration limits or LOQ-limits are a much more pragmatic way to enforce DUID legislation.

Identification and phylogenetic analysis of hepatitis C virus in forensic blood samples obtained from injecting drug users

Injecting drug users (IDUs) are a high-risk group for contracting hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) infections. In Japan, data on the prevalence of those blood-borne viruses among IDUs are very limited. Blood samples were obtained from 12 cadavers of IDUs sent to Nagoya City University for the purpose of judicious autopsy and two alive IDUs with hepatitis C referred to a local hospital at the same period. The viruses were detected by polymerase chain reaction and phylogenetic analysis was performed. Two (16.6%) of the 12 autopsy cases were positive for HCV, but no case was positive for either HBV or HIV. Phylogenetic analysis of the two HCV isolates revealed that one was classified into genotype 1b and another was genotype 2b. Furthermore, nucleotide sequences of two isolates recovered from IDUs with hepatitis C were identical, that indicated the transmission of HCV between them, and those HCV were phylogenetically classified into genotype 2a. The prevalence of HCV infection among IDUs in Japan, despite the case of judicious autopsy, seems to be high, but HIV infection seems to be rare. The transmission of HCV between IDUs was demonstrated, and this indicates that phylogenetic analysis would applicable to also forensic analysis. HCV isolates identified in this study did not phylogenetically segregate, thus multiple transmission route of HCV among IDUs seems be exist in Japan.

Methamphetamine blood concentrations in human abusers: application to pharmacokinetic modeling

Characterization of methamphetamine's (METH) dose-dependent effects on brain neurochemistry may represent a critical component for better understanding the range of resultant behavioral pathologies. Most human studies, however, have assessed only the effects of long term, high dose METH abuse (e.g., greater than 1000 mg/day) in individuals meeting DSM-IV criteria for METH dependence. Yet, for the majority of METH abusers, their patterns of METH exposure that consist of lower doses remain less well-characterized. In this study, blood samples were obtained from 105 individuals detained by police for possible criminal activity and testing positive for stimulants by EMIT assay. METH blood concentrations were subsequently quantified by GC-MS and were predominantly in the low micromolar range (0.1-11.1 microM), with median and mean values of 1.3 microM (0.19 mg/l) and 2 microM (0.3 mg/l), respectively. Pharmacokinetic calculations based on these measured values were used to estimate initial METH body burdens, the median value being 52 mg. Modeling a 52 mg dose for a 4 day-METH maintenance exposure pattern of 4 doses/day at 4 h intervals showed that blood concentrations remained between 1 and 4 microM during this period. Collectively, these data present evidence for a METH exposure pattern distinct from high dose-METH abuse and provide the rationale for assessing potential brain pathology associated with such lower dose-METH exposure.

Methamphetamine disposition in oral fluid, plasma, and urine

This review of the disposition of methamphetamine in oral fluid, plasma, and urine is based on a comprehensive controlled dosing study involving five healthy, drug-free research volunteers who resided on a closed clinical ward for 12 weeks. Subjects were administered four low (10 mg) and high (20 mg) daily oral doses of methamphetamine in two separate sessions. Near-simultaneous collections of oral fluid and plasma were performed on the first day of each low- and high-dose session. Thereafter, oral fluid was provided on each day of dosing by different oral fluid collection methods. All urine specimens were collected on an ad libitum basis throughout the study. Specimens were analyzed by gas-chromatography mass spectrometry for methamphetamine and the metabolite, amphetamine, with a limit of quantification of 2.5 ng/mL for each analyte. Methamphetamine and metabolite concentrations in oral fluid appeared to follow a similar time course in oral fluid as in plasma and were dose-proportional, but oral fluid concentrations exceeded plasma concentrations. Urine drug concentrations were substantially higher than those in oral fluid. Some drug accumulation was noted with daily dosing, but generally did not markedly influence detection times or detection rates of oral fluid tests. Detection times and detection rates for oral fluid and urine were determined at cessation of 4 days of dosing. Generally, detection times and rates for urine were longer than those observed for oral fluid at conventional cutoff concentrations. When contemplating selection of oral fluid as a test matrix, the advantages of oral fluid collection should be weighed against its shorter time of detection compared to that of urine.

Mechanism of an exaggerated locomotor response to a low-dose challenge of methamphetamine

Previous studies using phenylethylamine psychostimulants such as amphetamine (AMPH) have demonstrated that pretreatment with a high-dose of drug followed by a low-dose challenge injection (3 h later) results in an exaggerated behavioral response. In order to explore the mechanism of this exaggerated or what has been suggested to be a "sensitized" response, we investigated the effects of methamphetamine (METH) in a similar treatment paradigm. The current study found that, as suggested by previous studies, a low-dose challenge with METH substantially increased the locomotor response in animals that received a high-dose pretreatment (3.5 h prior to challenge). We also observed that rats displayed an increase in the concentrations of METH and its metabolite AMPH in the striatum following the low-dose challenge of METH if they were pretreated with METH versus saline. A similar pattern for METH and AMPH levels was measured in the plasma. Taken together, these results suggest that the accumulation of drug in animals pretreated with high-dose METH contributes to the overall enhanced behavioral response following challenges with low-doses of METH.

Chiral separation and quantification of R/S-amphetamine, R/S-methamphetamine, R/S-MDA, R/S-MDMA, and R/S-MDEA in whole blood by GC-EI-MS

The enantioselective composition of the amphetamines is of interest, as the enantiomers show differences in their pharmacological effects and several methods for chiral separation of amphetamines have been described. Only a few methods have used whole blood as matrix and none of these separates both classic amphetamines (amphetamine and methamphetamine) and designer amphetamines (MDA, MDMA and MDEA). The aim of this study was, therefore, to develop a method for enantioselective analysis of AM, MA, MDA, MDMA, and MDEA in whole blood. The amphetamines were extracted from 0.5 g of whole blood by liquid-liquid extraction. After derivatization with R-MTPCl, the resulting diastereomers were separated by GC on a HP-5MS column and detected by SIM-MS. R-MTPCl was used as derivatization reagent because of the stability of this reagent and good separation of these analytes. Through the method, development time and temperature of the derivatization were optimized, and by admixture of 0.02% triethylamine it became possible to detect the amphetamines in adequately low concentrations as more analytes were derivatized. The method was validated and it was linear from 0.004 to 3 microg/g per enantiomer. The accuracy was within 91-115%, while the repeatability and reproducibility were < or =15% R.S.D. A method suitable for enantioselective separation and analysis of the amphetamines has been achieved, and the method was applied to analysis of whole blood samples originating from traffic and criminal cases and post mortem cases.

Impairment related to blood amphetamine and/or methamphetamine concentrations in suspected drugged drivers

Experimental studies have investigated effects of low oral doses of amphetamine and methamphetamine on psychomotor functions, while less work has been done on effects of high doses taken by abusers in real-life settings. There are indications that intake of high doses may impair traffic related skills, and that abuse of amphetamines may cause hypersomnolence at the end-of-binge. The present study aimed at investigating the concentration-effect relationship between blood amphetamines concentrations and impairment in a population of real-life users. Eight hundred and seventy-eight cases with amphetamine or methamphetamine as the only drugs present in the blood samples were selected from the impaired driver registry at The Norwegian Institute of Public Health. In each case the police physician had concluded on whether the driver was impaired or not. 27% of the drivers were judged as not impaired, while 73% were judged as impaired. There was a positive relationship between blood amphetamines concentrations and impairment. The relationship reached a ceiling at blood amphetamines concentrations of 0.27-0.53 mg/l. Younger drivers were more often judged impaired than older drivers at similar concentrations. Despite the performance enhancing qualities of amphetamines demonstrated in some low dose laboratory experiments; this study revealed a positive relationship between blood amphetamines concentration and traffic related impairment.

Safety and efficiency of an anti-(+)-methamphetamine monoclonal antibody in the protection against cardiovascular and central nervous system effects of (+)-methamphetamine in rats

The purpose of these studies was to determine if a high-affinity, anti-(+)-methamphetamine (METH) monoclonal antibody (mAb6H4; KD=11 nM) protects against METH-induced central nervous and cardiovascular system effects in rats. Rats (n=5 per group) received one of three anti-METH mAb6H4 doses, equal to 0.32, 0.56 or 1 times the mole equivalent (mol-eq) amount of METH in the body following a 1 mg/kg i.v. METH dose. Each rat was challenged with METH (1 mg/kg, i.v.) 1 and 4 days after the anti-METH mAb dose. The 1 mol-eq anti-METH mAb dose significantly reduced the duration of METH-induced locomotor activity (horizontal locomotion and rearing events), heart rate and blood pressure effects from 2 to 3 h to about an hour. This resulted in a significant reduction in total locomotor activity and the area under the hemodynamic effect vs. time curve for heart rate and blood pressure. In addition, the time to peak locomotor activity was decreased after the 1 mol-eq mAb dose vs. the lower doses. These changes were limited to the first METH challenge. The responses to the second METH challenge were not different from baseline. The peak hemodynamic and locomotor activity values were unchanged after both challenges. These results indicate anti-METH mAb6H4 can safely reduce the hemodynamic and locomotor effects of METH given one day after anti-METH IgG, and that the mAb is safe when administered in the absence of METH. These results are important because they indicate these antibody medications have simultaneous beneficial effects in multiple organ systems.

Determination of l-methamphetamine: a case history

Methamphetamine was detected in a 77-year-old male who had a history of congestive heart failure. Using a modification of a previously reported method, trifluoroacetyl-l-prolyl chloride was used to derivatize sympathomimetic amines to allow separation and identification of individual enantiomers. The l-enantiomer of methamphetamine and a trace amount of l-amphetamine were found in blood and urine specimens from this case. Further investigation revealed the decedent had bronchial asthma and regularly used a Vicks Inhaler, which contains l-methamphetamine as the active ingredient.

The influence of amphetamine on language activation: an fMRI study

RATIONALE

Amphetamine administration has been found to affect the degree of cerebral dominance for motor control in animals. In humans, cerebral dopamine neurotransmission is also correlated to motor dominance. Since language dominance is related to motor dominance, amphetamine might also affect cerebral dominance for language.

METHODS

To test this hypothesis, language activation was measured twice with functional magnetic resonance imaging in ten healthy right-handed men in a double-blind crossover design 2 h after amphetamine or placebo administration.

RESULTS

Language-related activation increased significantly in task-related areas, but the individual lateralization index was not affected in the amphetamine condition as compared to placebo.

CONCLUSIONS

This finding suggests that short-termed alterations in the dopaminergic neurotransmission do not affect language dominance.

ELISA on a Microchip with a Photodiode for Detection of Amphetamine in Plasma and Urine

A rapid and sensitive assay was developed for the detection of amphetamine in plasma and urine. The method relies on the principle of competitive ELISA (enzyme-linked immunosorbent assay). A flow microchip with a total volume of 7 microL was used for the development of a chemiluminescent ELISA technique. Solutions, samples, and the chemiluminescence substrate were injected by a flow system, and a photodiode detector was used to measure the light intensity. The incubation time of the competitor (competition phase) was reduced to 10 min. Calibration curves corresponding to analyte concentrations ranging from 40 to 1,000 microg/L in urine samples and from 6 to 96 microg/L in plasma samples were obtained. The detection limits were in the region of 20 and 6 microg/L in urine and plasma, respectively. The main focus of the work was on speed, reliability, reproducibility, and operational stability of the assay. This method was proven readily adaptable to automation and provided reproducible results.

Quantitation of R-(-)- and S-(+)-Amphetamine in Hair and Blood by Gas Chromatography-Mass Spectrometry: An Application to Compliance Monitoring in Adult-Attention Deficit Hyperactivity Disorder Treatment

Amphetamine has been used in Attention Deficit Hyperactivity Disorder (ADHD), narcolepsy, and as an appetite suppressant either as the racemate or in different proportions of its enantiomers. In Linköping, Sweden, the Department for Drug Dependence has successfully treated drug abusers also diagnosed with Adult ADHD with Metamina [S-(+)-amphetamine]. Because of the high risk of relapse into drug abuse, a strategy involving the analysis of amphetamine enantiomers in blood and hair was investigated for the assessment of compliance as well as abstinence from street amphetamine. Four patients were included: one patient was treated with racemic amphetamine, and three with Metamina. Blood and hair samples were obtained as a part of the treatment. A basic extraction of the analytes into iso-octane was used. Hair was dissolved in sodium hydroxide before extraction. Chiral derivatization was performed by reaction with S-(-)-N-(trifluoroacetyl)prolyl chloride. Quantitation of R-(-)- and S-(+)-amphetamine was performed by gas chromatography-mass spectrometry in selected ion monitoring. Both blood and hair sample results showed good compliance for patients 1 and 2. Patient 3 and 4 showed different percentages of S-(+)-amphetamine in hair together with varying total concentrations, suggesting intake of additional racemic illicit amphetamine. During treatment, these patients also showed other signs of noncompliance, and one was temporarily withdrawn from treatment. We conclude that the method is suitable to detect therapeutic concentrations of R-(-)- and S-(+)-amphetamine in both blood and hair and that hair reveals noncompliance not shown by concentrations or enantiomer ratios in blood.

Abnormally high concentrations of amphetamine in blood of impaired drivers

We present a case series (N = 46) of individuals apprehended in Sweden for driving under the influence of drugs (DUID). These cases were selected because the concentrations of amphetamine in blood were abnormally high (> 5.0 mg/L), the highest being 17 mg/L. In comparison, the median blood-amphetamine concentration in a population of DUID offenders (N = 6,613) was 0.70 mg/L. Among the DUID suspects with extremely high blood-amphetamine concentrations there were 38 men (83%) with mean age of 37.8 y (SD 6.8 y) and 8 women (17%) with a mean age of 34.1 y (SD 4.3 y). All had previously been registered in our database (mean 12 times, median 9 times) for drug-related offences, including DUID. The concentration of amphetamine in blood of female offenders was slightly higher than the concentration in male offenders (6.6 mg/L vs. 5.8 mg/L), although this difference was not statistically significant (p > 0.05). The drugs other than amphetamine most frequently encountered in the blood samples were tetrahydrocannabinol and benzodiazepines (diazepam and nordiazepam). The commonest signs of drug use reported by the arresting police officers were bloodshot and glazed (watery) eyes, restlessness, talkativeness, exaggerated reflexes and slurred speech. Unsteady gait and dilated pupils were observed in some but not all individuals. These very high concentrations of amphetamine were tolerated without any fatalities indicating a pronounced adaptation to the pharmacologic effects of this central stimulant. Anecdotal information indicated that those with the very highest concentrations of amphetamine in blood had swallowed the drug to prevent being apprehended in possession of an illicit substance.

Amphetamine treatment similar to that used in the treatment of adult attention-deficit/hyperactivity disorder damages dopaminergic nerve endings in the striatum of adult nonhuman primates

Pharmacotherapy with amphetamine is effective in the management of attention-deficit/hyperactivity disorder (ADHD), now recognized in adults as well as in children and adolescents. Here we demonstrate that amphetamine treatment, similar to that used clinically for adult ADHD, damages dopaminergic nerve endings in the striatum of adult nonhuman primates. Furthermore, plasma concentrations of amphetamine associated with dopaminergic neurotoxicity in nonhuman primates are on the order of those reported in young patients receiving amphetamine for the management of ADHD. These findings may have implications for the pathophysiology and treatment of ADHD. Further preclinical and clinical studies are needed to evaluate the dopaminergic neurotoxic potential of therapeutic doses of amphetamine in children as well as adults.

Liquid-phase microextraction based on carrier mediated transport combined with liquid chromatography–mass spectrometry

Recently, we demonstrated for the first time liquid-phase microextraction (LPME) of polar drugs based on carrier mediated transport. In this new extraction technique, selected analytes were extracted as ion-pairs from small volumes of biological samples, through a thin layer of a water immiscible organic solvent immobilised in the pores of a porous hollow fibre (liquid membrane), and into a microl volume of an acidic aqueous acceptor solution placed inside the lumen of the hollow fibre. In the current paper, this new extraction technique was combined with liquid chromatography-mass spectrometry (LC-MS) for the first time. Carrier mediated LPME was evaluated for several new model drugs (0.01 <log P< 1.76), the sample clean-up aspects were investigated in detail, and this new extraction technique was fully validated for the first time. Extractions were performed from 50 microl of human plasma samples, which provided sufficient material in combination with LC-MS. Sodium octanoate (50 mM) was added to the sample as carrier, 1-octanol (approximately 15 microl) was used as the liquid membrane in the wall of the hollow fibre, and 50 mM HCl was utilized as acceptor solution in the lumen of the hollow fibre. The addition of carrier to the samples was found to significantly improve extraction recoveries for the polar drugs tested, providing recoveries in the range 16-78%. Validation was accomplished for atenolol and cimetidine. Limits of quantification (S/N = 5) from 50 microl of plasma were 25 and 50 ng/ml for atenolol and cimetidine, respectively. The intra-day precision (R.S.D.) ranged from 7.8 to 17.2% and from 9.5 to 14.1% for atenolol and cimetidine, respectively, and corresponding inter-day precisions (R.S.D.) were within 6.7-1.4% and 7.7-20.3%. The method was linear in the range 25-1500 ng/ml for atenolol (r = 0.992), and 50-3500 ng/ml for cimetidine (r = 0.976). The accuracy of the method was found to be in range 89.1-99.6% and 83.4-86% for atenolol and cimetidine, respectively. The sample clean-up obtained by carrier mediated LPME was excellent, providing a significantly lower back-ground level in total ion current chromatograms by LC-MS as compared to protein precipitation.

Quantitative drug levels in stimulant psychosis: relationship to symptom severity, catecholamines and hyperkinesia

To examine the relationship between quantitative stimulant drug levels, catecholamines, and psychotic symptoms, nineteen patients in a psychiatric emergency service with a diagnosis of amphetamine- or cocaine-induced psychosis were interviewed, and plasma and urine were collected for quantitative assays of stimulant drug and catecholamine metabolite levels. Methamphetamine or amphetamine levels were related to several psychopathology scores and the global hyperkinesia rating. HVA levels were related to global hyperkinesia but not to psychopathology ratings. Although many other factors such as sensitization may play a role, intensity of stimulant-induced psychotic symptoms and stereotypies appears to be at least in part dose-related.

Cognitive sequelae of intravenous amphetamine self-administration in rats: evidence for selective effects on attentional performance

Characterizing the nature and severity of cognitive deficits associated with chronic stimulant abuse may provide new insights into the neural substrates of drug addiction because such deficits may contribute to the chronic relapsing nature of compulsive drug use. This investigation examines in rats the long-term cognitive consequences of intravenously self-administered amphetamine, specifically on performance of a 5-choice serial reaction time task (5-CSRTT), which assesses visuo-spatial attention and impulsivity. Rats experienced 5 days of intravenous (i.v.) amphetamine self-administration and were then withdrawn for a period of 9 days, during which time testing on the 5-CSRTT took place. This was repeated on five consecutive occasions for a period of 10 weeks. Controls experienced identical training on the 5-CSRTT but during the self-administration sessions received yoked i.v. infusions of normal saline. The results reveal a selective and reproducible pattern of deficits on the 5-CSRTT following repeated withdrawal from amphetamine self-administration, with deleterious effects on the speed and accuracy of responding as well as increased omission errors. Premature (impulsive) responding, perseveration, and food consumption latencies were not significantly affected. Deficits in attentional performance fully recovered 4-5 days after amphetamine cessation and there was no evidence of any long-term disturbances, even when the attentional load was increased. However, following a 2-month abstinence period, abnormalities in the subsequent effects of acute noncontingent amphetamine were found, with increased omissions, slower response times, and reduced impulsivity. Thus, contingent i.v. amphetamine administration has both short- and long-term consequences, which may be relevant to the complex disturbances that accompany drug addiction.

High concentrations of diazepam and nordiazepam in blood of impaired drivers: association with age, gender and spectrum of other drugs present

A zero-concentration limit for controlled scheduled drugs in the blood of motorists was introduced in Sweden in 1999 and the annual number of arrests for driving under the influence of drugs (DUID) has since increased eight-fold. However, for prescription drugs that might cause impairment (e.g. benzodiazepines) additional proof is needed to justify prosecution, such as whether the medication was being misused. Over a 2-year period, we found 94 cases of DUID in which the concentrations of diazepam in blood was 1.1 microg/g or more. Diazepam (D) and nordiazepam (ND) were determined in whole blood by capillary gas chromatography with a limit of quantitation of 0.05 microg/g for each compound. The mean (median) and maximum concentrations of D were 2.0 microg/g (1.7 microg/g) and 7.8 microg/g and the corresponding ND concentrations were 1.5 microg/g (1.0 microg/g) and 7.6 microg/g, respectively. The concentration of D in blood exceeded 2 microg/g in 21% of cases and was over 3.0 microg/g in 11% of cases. D and ND were the only drugs present in eight cases (seven men and one women) and in another five cases ethanol was present at concentrations ranging from 0.81 to 1.98 mg/g. Polydrug use was very common in these DUID suspects and D and ND coexisted with amphetamine in 20% of cases, tetrahydrocannabinol in 18% of cases and with both these illicit drugs in 12% of cases. The next most prevalent drug combination was D, ND and morphine (mostly derived from heroin), seen in 13% of cases. Other psychoactive prescription drugs were identified in blood including alprazolam, flunitrazepam, oxazepam, zolpidem and zopiclone. This case series of DUID suspects demonstrate the high frequency of polydrug use showing preference for illicit drugs like amphetamine, cannabis and heroin, in that order. Furthermore, Swedish traffic delinquents frequently overdose with prescription drugs as exemplified here by unusually high concentrations of D and its active metabolite ND.

Fenproporex N-dealkylation to amphetamine—enantioselective in vitro studies in human liver microsomes as well as enantioselective in vivo studies in Wistar and Dark Agouti rats

Fenproporex (FP) is known to be N-dealkylated to R(-)-amphetamine (AM) and S(+)-amphetamine. Involvement of the polymorphic cytochrome P450 (CYP) isoform CYP2D6 in metabolism of such amphetamine precursors is discussed controversially in literature. In this study, the human hepatic CYPs involved in FP dealkylation were identified using recombinant CYPs and human liver microsomes (HLM). These studies revealed that not only CYP2D6 but also CYP1A2, CYP2B6 and CYP3A4 catalyzed this metabolic reaction for both enantiomers with slight preference for the S(+)-enantiomer. Formation of amphetamine was not significantly changed by quinidine and was not different in poor metabolizer HLM compared to pooled HLM. As in vivo experiments, blood levels of R(-)-amphetamine and S(+)-amphetamine formed after administration of FP were determined in female Dark Agouti rats (fDA), a model of the human CYP2D6 poor metabolizer phenotype (PM), male Dark Agouti rats (mDA), an intermediate model, and in male Wistar rats (WI), a model of the human CYP2D6 extensive metabolizer phenotype. Analysis of the plasma samples showed that fDA exhibited significantly higher plasma levels of both amphetamine enantiomers compared to those of WI. Corresponding plasma levels in mDA were between those in fDA and WI. Furthermore, pretreatment of WI with the CYP2D inhibitor quinine resulted in significantly higher amphetamine plasma levels, which did not significantly differ from those in fDA. The in vivo studies suggested that CYP2D6 is not crucial to the N-dealkylation but to another metabolic step, most probably to the ring hydroxylation. Further studies are necessary for elucidating the role of CYP2D6 in FP hydroxylation.

Development of a liquid chromatography–tandem mass spectrometric method for the determination of methamphetamine and amphetamine using small volumes of rat serum

The aim of this paper was to develop LC/MS/MS methodology for the determination of methamphetamine (METH) and amphetamine (AMP) using low microliter volumes (20-150 microl) of rat serum and demonstrate the use of this method for the study of serum pharmacokinetics in the rat. The analytes were extracted from rat serum using solid-phase extraction followed by an isocratic separation on a narrow-bore Hypersil C(18) column. Lower limits of quantitation for METH and AMP were 0.3 ng/ml using positive ion electrospray tandem mass spectrometry. The accuracy of the method was within 20% of the actual values over a wide range of serum concentrations. The within-day and between-day precision was better than 20% (R.S.D.). Ion-suppression matrix effects on electrospray ionization were evaluated for extracted rat serum. The LC/MS/MS method was further validated by comparing serum concentrations of METH and AMP to serum concentrations previously determined using an LC/[ (3)H]-METH assay with radiochemical detection. Finally, the LC/MS/MS method was used to study the pharmacokinetics of METH and AMP after a 1mg/kg intravenous bolus dose of METH to female Sprague-Dawley rats.

Striatal amphetamine-induced dopamine release in patients with schizotypal personality disorder studied with single photon emission computed tomography and [123I]iodobenzamide

BACKGROUND

Previous imaging studies demonstrated that schizophrenia is associated with increased amphetamine-induced dopamine (DA) release in the striatum, most pronounced during episodes of illness exacerbation. Schizotypal personality disorder (SPD) is a schizophrenia spectrum disorder, genetically related to schizophrenia. The goal of this study was to investigate striatal DA function in patients with SPD.

METHODS

In our study, 13 SPD patients and 13 matched healthy control subjects underwent single photon emission computed tomography (SPECT) scan during bolus plus constant infusion of the D2/3 radiotracer [123I]iodobenzamide (IBZM). Striatal specific to nonspecific equilibrium partition coefficient (V(3)") was measured at baseline and following amphetamine administration (.3 mg/kg).

RESULTS

No significant differences were observed in baseline V(3)" between groups. Amphetamine induced a larger decrease in [123I]IBZM V(3)" in SPD patients (-12 +/- 5%) compared with control subjects (-7 +/- 5%, p =.03).

CONCLUSIONS

The reduction in [123I]IBZM V(3)" induced by amphetamine in SPD was similar to that observed in remitted schizophrenia patients (-10 +/- 9%, n = 17), but significantly lower than that observed during illness exacerbation (-24 +/- 13%, n = 17). This suggests that DA dysregulation in schizophrenia spectrum disorders might have a trait component, present in remitted patients with schizophrenia and in SPD, and a state component, associated with psychotic exacerbations but not SPD.

A new formulation of selegiline: improved bioavailability and selectivity for MAO-B inhibition

Seven randomised comparative studies were conducted in healthy volunteers to compare the pharmacokinetic and pharmacodynamic profiles of selegiline hydrochloride in a new formulation designed for buccal absorption "Zydis Selegiline" (1.25-10 mg) with conventional selegiline hydrochloride tablets "conventional selegiline tablets" (10 mg). A total of 156 healthy volunteers participated in these studies. Plasma concentrations of selegiline and its primary metabolites, N-desmethylselegiline (DMS), l-amphetamine (AMT), and l-methamphetamine (MET) were measured using Gas Chromatography Mass Spectrometry (GCMS) and gas liquid chromatography (GLC) assays. Inhibition of monoamine-oxidase type B (MAO-B) and monoamine oxidase type A (MAO-A) activity was determined by measurement of as beta-phenylethylamine (PEA) by GCMS and 5-hydroxyindoleacetic acid (5-HIAA) by High Performance Liquid Chromatography (HPLC) assays. Almost a third (2.96 mg) of a 10 mg selegiline dose in Zydis Selegiline was absorbed pre-gastrically (predominantly buccally) within 1 minute. Mean [SD] area-under-the curve (AUC(0- infinity)) values following Zydis Selegiline 10 mg (5.85 [7.31] ng.h/mL) were approximately five times higher than those following conventional selegiline tablets 10 mg (1.16 [1.05] ng.h/mL). In contrast, plasma concentrations of metabolites were significantly ( p<0.001) lower following Zydis Selegiline 10 mg than following conventional selegiline tablets 10 mg. Plasma concentrations of selegiline and its metabolites increased in a dose-dependent manner over the dose-range Zydis Selegiline 1.25-5 mg. Bioavailability was determined using AUC and peak plasma concentrations (C(max)). The C(max) of selegiline was similar following administration of Zydis Selegiline 1.25 mg (1.52 ng/mL) or conventional selegiline tablets 10 mg (1.14 mg/mL). The range of values for AUC(0- infinity) and C(max) following Zydis Selegiline 1.25 mg were entirely contained within the range following conventional selegiline tablets 10 mg, with a much higher variability of plasma selegiline concentrations occurring after conventional selegiline tablets than after Zydis Selegiline. As expected, peak plasma concentrations for DMS, AMT and MET were consistently lower after Zydis Selegiline 1.25 mg (1.19, 0.34, 0.93 ng/ml, respectively) than after conventional selegiline tablets 10 mg (18.37, 3.60, 12.92 ng/ml, respectively). A significant (r=0.0001) correlation between daily PEA excretion (a measure of brain MAO-B inhibition) and the log-transformed AUC((0-t)) for selegiline was demonstrated. Mean daily PEA excretion was similar following Zydis Selegiline 1.25 mg and conventional selegiline tablets 10 mg (13.0 microg versus 17.6 microg). In contrast, there was no correlation between PEA excretion and selegiline metabolites, indicating that selegiline metabolites do not significantly inhibit MAO-B. Urinary excretion of 5-HIAA (used as a marker for MAO-A inhibition) was unrelated to plasma concentrations of selegiline or DMS following single or repeat dosing of Zydis Selegiline 1.25 mg or conventional selegiline tablets 10 mg. However, comparison of treatment groups revealed a significantly lower excretion of 5-HIAA in the conventional selegiline tablets 10 mg group than in the Zydis Selegiline 1.25 mg group after repeated administration over 13 days. In summary, by reducing the opportunity for first-pass metabolism, the absorption of selegiline from Zydis Selegiline was more efficient and less variable than from conventional selegiline tablets. Compared with conventional selegiline tablets 10 mg, Zydis Selegiline 1.25 mg yielded similar plasma concentrations of selegiline and degree of MAO-B inhibition, but markedly reduced concentrations of the principal metabolites. Thus, the lower but equally MAO-B inhibitory dose of selegiline in Zydis Selegiline 1.25 mg, which is associated with lower concentrations of potentially harmful metabolites, could offer a safer and more predictable treatment in the management of patients with Parkinson's disease.

Nutritional status of deceased illicit drug addicts in Stockholm, Sweden--a longitudinal medicolegal study

Autopsy investigations, toxicological analyses, and calculation of body mass index were performed in 1180 deceased illicit drug addicts (IDAs) in Stockholm. Sweden during 1988-2000, i.e., during a period of time when the general population in numerous countries showed a dramatic increase in the prevalence of overweight. Nutritional deficit in IDAs has been pointed out as a threat to their health as well as to their quality of life. The prevalence of overweight in deceased IDAs increased from 27.4% in 1988 to 45.5% in 2000. The prevalence of overweight among all heroin users, heroin injectors, methadone, cocaine, and amphetamine users was 36.0, 38.4, 43.1, 45.0 and 50.9%, respectively, the lowest prevalence being among users of cannabis alone and HIV-positive IDAs (22.0 and 16.1%, respectively). In conclusion, Stockholm's IDAs are affected by the past decade's dramatically increased prevalence of overweight, at least to the same degree as the general population. The increased body weight seems not to influence the danger of dying upon heroin administration.

In vivo vulnerability to competition by endogenous dopamine: Comparison of the D2 receptor agonist radiotracer (-)-N-[11C]propyl-norapomorphine ([11C]NPA) with the D2 receptor antagonist radiotracer [11C]-raclopride

(-)-N-Propyl-norapomorphine (NPA) is a full dopamine (DA) D2 receptor agonist and [11C]NPA is a suitable radiotracer to image D2 receptors configured in a state of high affinity for agonists with positron emission tomography (PET). In this study the vulnerability of the in vivo binding of [11C]NPA to acute fluctuation in synaptic DA was assessed with PET in baboons and compared to that of the reference D2 receptor antagonist radiotracer [11C]raclopride. Three male baboons were studied with [11C]raclopride and [11C]NPA under baseline conditions and following administration of the potent DA releaser amphetamine (0.3, 0.5, and 1.0 mg kg(-1) i.v.). Kinetic modeling with an arterial input function was used to derive the striatal specific-to-nonspecific equilibrium partition coefficient (V3"). [11C]Raclopride V3" was reduced by 24 +/- 10%, 32 +/- 6%, and 44 +/- 9% following amphetamine doses of 0.3, 0.5, and 1.0 mg kg(-1), respectively. [11C]NPA V3" was reduced by 32 +/- 2%, 45 +/- 3%, and 53 +/- 9% following amphetamine doses of 0.3, 0.5, and 1.0 mg kg(-1), respectively. Thus, endogenous DA was more effective at competing with [11C]NPA binding compared to [11C]raclopride binding, a finding consistent with the pharmacology of these tracers (agonist vs. antagonist). These results also suggest that 71% of D2 receptors are configured in a state of high affinity for agonists in vivo. In conclusion, [11C]NPA might provide a superior radiotracer to probe presynaptic DA function with PET in health and disease.

Effects of amphetamine on immune-mediated lung inflammatory response in rats

OBJECTIVE

The present study analyzed the effects of acute amphetamine (AMPH) treatment on immune-mediated lung inflammatory response in rats.

METHODS

There were four experiments. In the first and second experiments, rats were treated with AMPH (1 mg/kg) or 0.9% NaCl, and locomotor activity (experiment 1) and serum AMPH concentrations (experiment 2) were measured 1 or 12 h after treatment. In the third experiment, rats which were immunized with ovalbumin (OVA) were treated 14 days later with 0.9% NaCl or AMPH (1 mg/kg). Twelve hours after these treatments, all animals were submitted to challenge by 1% OVA inhalation being analyzed afterwards for bronchoalveolar lavage fluid (BAL), peripheral blood and bone marrow cellularity. In the fourth and final experiment, rats were treated and studied as for experiment 3, except that half of the animals within each group were previously treated with metyrapone prior to the OVA challenge.

RESULTS

In the non-immunized rats, AMPH treatment induced an increase in locomotor activity synchronized to high serum AMPH concentrations 1 h after, but not 12 h after treatment. In OVA-challenged rats, AMPH treatment decreased the total number of inflammatory cells, recovered in both BAL and peripheral blood and increased the total number of bone marrow cells. These effects, observed 1 day after OVA challenge, were abrogated by previous metyrapone treatment.

CONCLUSION

AMPH treatment changed HPA-axis responsiveness to the stress condition imposed by the OVA challenge decreasing lung and blood leukocytes cellularity most probably via corticosterone actions on bone marrow activity.

Concentrations and Ratios of Amphetamine, Methamphetamine, MDA, MDMA, and MDEA Enantiomers Determined in Plasma Samples from Clinical Toxicology and Driving Under the Influence of Drugs Cases by GC-NICI-MS*

Enantiomers of amphetamine (AM), methamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), and 3,4-methylenedioxyethylamphetamine (MDEA) exhibit different pharmacological properties. This may be important for the interpretation of analytical results. Plasma samples were analyzed using validated negative ion chemical ionization gas chromatography-mass spectrometry procedures. The results for clinical toxicology cases, divided into screening (SCR) and intoxication (ITX) cases, and those of driving under the influence of drugs (DUID) cases were compared. The concentrations of all enantiomers, except R-(-)-MDA and R-(-)- and S-(+)-MA, in the SCR samples were lower than in ITX and DUID samples. Differences between concentrations in ITX and DUID samples were only significant for both enantiomers of AM (DUID higher). These findings suggested impairment in drugged drivers. Different enantiomer ratios (R vs. S) were found for AM between DUID and SCR samples, for MDMA between ITX and SCR samples, and for MDA between DUID and ITX and DUID and SCR samples. Higher MDMA enantiomer ratios in SCR compared to ITX samples are in accordance with a previously described increase of those ratios over time, possibly allowing differentiation of recent from nonrecent ingestion. Pharmacokinetic analysis of a MDMA poisoning yielded elimination half-lives of 6.0 h for R-(-)-MDMA and 4.1 h for S-(+)-MDMA. The enantiomer ratios rose exponentially over time.

Routine analysis of amphetamine and methamphetamine in biological materials by gas chromatography-mass spectrometry and on-column derivatization

A simple determination method of amphetamine (AP) and methamphetamine (MA) in biological materials was developed using on-column derivatization and gas chromatography-mass spectrometry (GC-MS). AP and MA in biological materials were adsorbed on the surface of Extrelut and then extracted and derivatized simultaneously on the Extrelut column. AP and MA were derivatized to the N-propoxycarbonyl derivatives using propylchloroformate. Pentadeuterated MA was used as an internal standard. The recoveries of AP and MA from urine were 88.2 and 92.5%, and those from blood were 89.7 and 90.3%, respectively. The calibration curves showed linearity in the range of 12.5-2000 ng/ml (ng/g) for AP and MA in urine and blood, and 0.25-20 ng/mg in hair. When urine samples containing two different concentrations (200 and 1000 ng/ml) of AP and MA, blood samples containing two different concentrations (200 and 1000 ng/g) of AP and MA, hair samples containing two different concentrations (0.5 and 5.0 ng/mg) of AP and MA, the coefficients of variation of intra-day and inter-day were 0.68-3.60% in urine, 0.42-4.58% in blood, and 1.20-13.1% in hair. Furthermore, this proposed method was applied to a medico-legal case of MA intoxication.

Three fatal cases of PMA and PMMA poisoning in Denmark

Paramethoxyamphetamine (PMA) and paramethoxymetamphetamine (PMMA) are methoxylated phenylethylamine derivatives with effects similar to methylenedioxymetamphetamine (MDMA) and sold as such. However, PMA and PMMA are more potent than MDMA, but have a slower onset of action, which encourages users to take more. Three fatal cases involving PMA and PMMA in Denmark in year 2000 are investigated including history, pathological, and toxicological findings. The methods used for extraction, identification, and quantitation of PMA and PMMA are described. In two of the cases, lethal postmortem blood concentrations of PMA and PMMA were determined at 3.4 and 3.3 mg/kg (case 1) and 0.78 and 0.68 mg/kg (case 3), respectively. In addition, other drugs such as MDMA, tetrahydrocannabinol, cocaine, and alcohol were involved in these cases. In the third case, death occurred four days after the ingestion of tablets containing PMA and PMMA, and therefore only low postmortem concentrations of PMA and amphetamine were detected. However, in a serum sample taken at admission to the hospital, PMA and PMMA were found, but not quantitated. It is believed that the cause of death in case 2, multiple-organ failure, was caused by overdoses of PMA and PMMA.

Quantitative analysis of desmethylselegiline, methamphetamine, and amphetamine in hair and plasma from Parkinson patients on long-term selegiline medication

Hair and plasma from patients on long-term selegiline medication were analyzed to evaluate the relationships between plasma and hair melanin concentrations and the incorporation of the selegiline metabolites methamphetamine and amphetamine in hair, and to evaluate hair analyses for determining compliance in medication. Analyses were performed on both the whole hairs, as well as pigmented and non-pigmented hairs from gray-haired patients. Melanin was quantitated by spectrophotometry, and metabolites were quantitated by gas chromatography-mass spectrometry. Concentrations in pigmented and non-pigmented hairs differed significantly for both methamphetamine (p < 0.01) and amphetamine (p < 0.02), with mean concentration ratios being 3.69 +/- 1.88 and 2.95 +/- 1.16 for methamphetamine and amphetamine, respectively. Segmental analysis indicated that some patients had not been compliant with medication. We concluded that the incorporation of methamphetamine and amphetamine into hair of single individuals shows a preference for pigmented hairs over white hairs and that segmental analysis of hair may be useful when measuring compliance with medication.

Development of a rapid and sensitive method for the quantitation of amphetamines in human plasma and oral fluid by LC-MS-MS

Target analysis of amphetamines in biological samples is of great importance for clinical and forensic toxicologists alike. At present, most laboratories analyze such samples by gas chromatography-mass spectrometry. However, this procedure is labor-intensive and time-consuming, particularly as a preliminary extraction and derivatization are usually unavoidable. Here we describe the development of an alternative method. Amphetamines were isolated from human plasma and oral fluid using a simple methanol precipitation step and subsequently analyzed using reversed-phase liquid chromatography-tandem mass spectrometry. Quantitation of the drugs was performed using multiple reaction monitoring. The developed method, which requires only 50 microL of biological sample, has a total analysis time of less than 20 min (including sample preparation) and enables the simultaneous quantitation of 3,4-methylenedioxymethamphetamine, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxyethylamphetamine, amphetamine, methamphetamine, and ephedrine in a single chromatographic run. Limits of detection of 2 microg/L or better were obtained. The method has been validated and subsequently applied to the analysis of plasma and oral fluid samples collected from current drug users.

A fatal paramethoxymethamphetamine intoxication

During the last years in Germany a marked increase in the use of amphetamines such as 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) has been observed. The use of these recreational drugs is especially common among young people participating in rave parties. Occasionally ring-methoxylated phenethylamine derivatives like paramethoxymethamphetamine (PMMA) or paramethoxyamphetamine (PMA) are found in street drugs offered as ecstasy. These compounds exhibit a higher toxicity than the methylenedioxyamphetamine derivatives. We report on the death of a 22-year-old man after the ingestion of ecstasy pills containing PMMA and PMA. The PMMA concentration in femoral blood was 0.85 mg/l. Besides PMA (0.61 mg/l), amphetamine (0.21 mg/l), benzoylecgonine (<0.01 mg/l) and ethanol (0.46 per thousand ) were found in the blood. The case reflects the well-known fact that street drugs offered as ecstasy pills contain not necessarily MDMA but frequently differ in composition even if they have the same logo. Users of these pills therefore always take the risk of consuming pills with dangerous life-threatening ingredients. In many laboratories paramethoxyamphetamines are not detectable in routine analytical procedures. If the cause of an intoxication cannot be discovered by analytical routine methods, rarely occurring designer drugs such as PMA or PMMA should also be kept in mind.

Pharmacodynamic mechanisms of monoclonal antibody-based antagonism of (+)-methamphetamine in rats

Our studies examined pharmacokinetic mechanisms involved in high-affinity (K(d) approximately 11 nM) monoclonal antibody-based antagonism of (+)-methamphetamine-induced locomotor effects. Male rats received (+)-methamphetamine (0.3, 1, or 3 mg/kg i.v.) followed 30 min later by saline or anti-(+)-methamphetamine monoclonal antibody. All groups received a constant dose of monoclonal antibody that was equimolar in binding sites to the body burden of a 1 mg/kg i.v. (+)-methamphetamine dose 30 min after administration. The monoclonal antibody antagonized locomotor effects due to 0.3 and 1 mg/kg (+)-methamphetamine. In contrast, monoclonal antibody treatment increased locomotor activity due to 3 mg/kg (+)-methamphetamine. We also investigated the serum and brain pharmacokinetics of (+)-methamphetamine without and with the monoclonal antibody. Rats received (+)-methamphetamine (1 mg/kg i.v.) followed by saline or monoclonal antibody treatment at 30 min. The monoclonal antibody significantly increased serum methamphetamine concentrations and significantly decreased brain methamphetamine concentrations. These data indicate that anti-(+)-methamphetamine monoclonal antibody-induced pharmacodynamics are complex, but are related to time-dependent changes in (+)-methamphetamine brain distribution.

Performance of immunoassays in screening for opiates, cannabinoids and amphetamines in post-mortem blood

Several immunoassay methods for screening of abused drugs in whole blood were evaluated in post-mortem forensic toxicology. Blood samples known to be positive or negative for opiates, cannabinoids or amphetamines by gas chromatography-mass spectrometry (GC-MS) were analysed by EMIT II Plus and EMIT d.a.u., Syva RapidTest and Triage 8 after acetone precipitation. In these experiments, the EMIT immunoassay method was modified by using the Dade Behring VIVA analyser to detect substances more sensitively. Low concentrations of abused drugs were detected in blood samples. The sensitivities of the modified EMIT method for opiates, cannabinoids and amphetamines were 100, 86 and 98%, respectively, whereas the values were below 86% with the other methods. The specificities of all immunoassay methods for opiates and cannabinoids were 83% or above but 51-85% for amphetamines. Sample rejection occurred in a few cases with the EMIT amphetamine assays. The modified EMIT immunoassay system presented here seems to be useful for screening of drugs of abuse in post-mortem blood samples, especially when urine is not available.

Interpretations of the TDxFLx calibration data of the abused drugs

The useful TDxFLx calibration data was obtained for the interpretation of the interactions of the abused drugs to sheep antiserum protein. The antibody of TDxFLx calibrators was prepared from sheep antiserum. Furthermore these data can be used to interpret the abused drug-protein binding phenomena in human body and the TDxFLx screening results of the abused drugs in urine samples. TDxFLx system uses fluorescence polarization immunoassay technique that is a competitive binding immunoassay methodology to allow tracer-labeled antigen (*Drug) and patient antigen (Drug) to compete for the same binding sites on the antibody molecules of sheep antiserum. To obtain the binding parameters, binding constant (K) and number of independent binding site (n), generally, Scatchard equation is used. This Scatchard equation is expressed in the concentration terms of free drug, bound drug, and protein (antibody). The binding parameters can not be obtained by applying the TDxFLx calibration data to the Scatchard equation directly because the TDxFLx calibration data are composed of the fluorescence polarization and the total drug concentrations. To obtain the binding parameters from the TDxFLx calibration data the new useful equation which was expressed in the total concentrations of drug and fluorescence polarization should be derived. Derivation of new equation was based on the Scatchard equation. The TDxFLx calibration data was curve fitted to the derived equation using KaleidaGraph program and Macintosh computer. The binding constant (K) and the number (n(P(t))) of binding site of 11-nor-delta(9)-tetrahydrocannabinol-9-carboxylic acid (COOH.THC) on the antibody were 1.14 x 10(8)l/mole and 4.04 x 10(-7)M, respectively. The binding constant and the number (n(P(t))) of binding site of amphetamine were 5.15 x 10(5)l/mole and 2.05 x 10(6)M, respectively. In case of COOH.THC the fluorescence polarization decreased linearly with the concentration. However, in case of amphetamine or the other three abused drugs the fluorescence polarizations decreased exponentially with their concentrations.

Methamphetamine and amphetamine pharmacokinetics in oral fluid and plasma after controlled oral methamphetamine administration to human volunteers

BACKGROUND

Methamphetamine (METH) and amphetamine (AMP) concentrations in 200 plasma and 590 oral fluid specimens were used to evaluate METH pharmacokinetics and pharmacodynamics after oral administration of sustained-release METH.

METHODS

Eight participants received four oral 10-mg S-(+)-METH hydrochloride sustained-release tablets within 7 days. Three weeks later, five participants received four oral 20-mg doses. Blood samples were collected for up to 24 h and oral fluid for up to 72 h after drug administration.

RESULTS

After the first oral dose, initial plasma METH detection was within 0.25-2 h; c(max) was 14.5-33.8 micro g/L (10 mg) and 26.2-44.3 micro g/L (20 mg) within 2-12 h. In oral fluid, METH was detected as early as 0.08-2 h; c(max) was 24.7-312.2 micro g/L (10 mg) and 75.3-321.7 micro g/L (20 mg) and occurred at 2-12 h. The median oral fluid-plasma METH concentration ratio was 2.0 across 24 h and was highly variable. Neutral cotton swab collection yielded significantly higher METH and AMP concentrations than citric acid candy-stimulated expectoration. Mean (SD) areas under the curve for AMP were 21% +/- 25% and 24% +/- 11% of those observed for METH in plasma and oral fluid, respectively. After a single low or high dose, plasma METH was >2.5 micro g/L for up to 24 h in 9 of 12 individuals (mean, 7.3 +/- 5.5 micro g/L at 24 h); in oral fluid the detection window was at least 24 h (mean, 18.8 +/- 18.0 micro g/L at 24 h). The plasma and oral fluid 24-h METH detection rates were 54% and 60%, respectively. After four administrations, METH was measurable for 36-72 h (mean, 58.3 +/- 14.5 h).

CONCLUSIONS

Perceived advantages of oral fluid for verifying METH exposure compared with urine include simpler specimen collection and reduced potential for adulteration, but urine offers higher analyte concentrations and a greater window of detection.

[Fatal poisoning due to narcotic abuse in the analytic-toxicological practice of Forensic Medicine Department Silesian Medical Academy in Katowice in years 1996-202]

147 cases of fatal poisonings in people due to narcotic abuse examined in the Forensic Medicine Department Silesian School of Medicine, Katowice in the years 1996-2002 have been presented in the paper. In the group examined there were 126 males and 21 females at the age of 16-44. Opium narcotics were found in 139 out of 147 cases and amphetamine derivatives in 18. Opiates were indicated in 58 individuals and amphetamine only in 8. In 35 poisoned people opiates with barbituric acid derivatives were found. In 3 cases death resulted after taking opiates and amphetamine derivatives. 1 individual died after taking opiates and substances of the phenothiazine group. In the organic fluids of 18 people opiates and medicines being derivatives of 1,4-benzodiazepine and barbituric acid were found. Amphetamine and derivatives of 1,4-benzodiazepine were found in 6 individuals and opiates, barbiturates, benzodiazepines and amphetamine in 1 individual. Concentrations of all the substances indicated ranged widely and were as follows: < 0.10-17.40 > microgram/ml for opiates; < 0.24-30.00 > microgram/ml for amphetamine; < 0.12-1.90 > microgram/ml for 1.4-benzodiazepine derivatives and < 0.18-15.24 > microgram/ml for barbituric acid derivatives. Ethanol was found in 18 individuals and its concentration was < 0.2-2.5 >@1000.

Enantioselective trace analysis of amphetamine in human plasma by gas chromatography/negative ion chemical ionization mass spectrometry

A method for the quantitative enantioselective analysis of amphetamine in human plasma by gas chromatography/negative ion chemical ionization mass spectrometry (GC/NICI-MS) is presented. Five-fold deuterated analogues of both enantiomers were used as internal standard. Plasma sample preparation was performed by a rapid liquid-liquid extraction using n-hexane. Derivatization with (S)-(-)-N-(heptafluorobutyryl)prolyl chloride was accomplished directly in the n-hexane extract to avoid loss of amphetamine during sample concentration. The method was validated in the expected concentration range of 0.006 for a pharmacokinetic study. Calibration curves were linear within a range 0.006-50 ng/mL plasma. Precision and accuracy were acceptable over the entire calibration range. Baseline separation of the enantiomers was easily achieved on a 15-m nonchiral apolar column. The method is simple and robust, and has been applied to the batch analysis of amphetamine enantiomers.

[Fatal intoxication with paramethoxyamphetamine]

From August to December of the year 2000 we ascertained 7 rapid deaths because of acute intoxication with tablets colloquially called Ufo. There were five men and two women aged from 20 to 29 (average 24) years. Analytic tests showed that one tablet of Ufo contains 40 mg of paramethoxyamphetamine, 1.0 mg of amphetamine, 0.05 mg of methamphetamine, 0.03 mg of 3-4-methylenedioxymethamphetamine. The levels of paramethoxyamphe-tamine in the blood of the deceased, determined by gas chromatography, were from 0.68 to 10.0 (approx. 3.2) mg/L and in the urine from 16 to 64 (approx. 35) mg/L. The press and television campaign caused elimination of fatal intoxications with parametoxy-amphetamine during the last 13 months.