Determination of methadone and its metabolites EDDP and EMDP in human hair by headspace solid-phase microextraction and gas chromatography-mass spectrometry

Microphysiological system to address the opioid crisis: A novel multi-organ model of acute opioid overdose and recovery

Opioids have been the primary method used to manage pain for hundreds of years, however the increasing prescription rate of these drugs in the modern world has led to a public health crisis of overdose related deaths. Naloxone is the current standard treatment for opioid overdose rescue, but it has not been fully investigated for potential off-target toxicity effects. The current methods for pharmaceutical development do not correlate well with pre-clinical animal studies compared to clinical results, creating a need for improved methods for therapeutic evaluation. Microphysiological systems (MPS) are a rapidly growing field, and the FDA has accepted this area of research to address this concern, offering a promising alternative to traditional animal models. This study establishes a novel multi-organ MPS model of acute opioid overdose and rescue to investigate the efficacy and off-target toxicity of naloxone in combination with opioids. By integrating primary human and human induced pluripotent stem cell (hiPSC)-derived cells, including preBötzinger complex neurons, liver, cardiac, and skeletal muscle components, this study establishes a novel functional multi-organ MPS model of acute opioid overdose and rescue to investigate the efficacy and off-target toxicity of naloxone in combination with opioids, with clinically relevant functional readouts of organ function. The system was able to successfully exhibit opioid overdose using methadone, as well as rescue using naloxone evidenced by the neuronal component activity. In addition to efficacy, the multi-organ platform was able to characterize potential off-target toxicity effects of naloxone, specifically in the cardiac component.

Outside-in hair contamination by blood containing opiates and opioids

Hair analysis for drugs has become extensively used for forensic investigation in recent years. To best interpret hair drug content in post-mortem conditions, the extent of external contamination by biological fluids, such as blood, must be taken into account to avoid false positive results. The present study evaluated opiates and opioids incorporation into hair from blood containing different concentrations of morphine (MOR), 6-mono-acetyl morphine (6-AM), codeine (COD), dihydrocodeine (DHC), tramadol (TRA), oxycodone (OXY), methadone (MET), 2-ethylidene-1,5-dimethyl-3,3- diphenyl pyrrolidine (EDDP), buprenorphine (BUP) and norbuprenorphine (NBUP). The hair strands contaminated by brief soaking into blood were stored at room temperature (RT) or at 4°C during 6 hours, 1, 3, 7 or 14 days. After decontamination by extensive washing, we show that all opiates and opioids were incorporated into hair within a few hours at RT and 4°C, without significant changes over time. The concentrations of opiates and opioids in hair reached the cut-off levels established by the Society of Hair Testing (SoHT) for therapeutic (MET, COD), or toxic or lethal (all other molecules) blood concentrations. The metabolite to parent drug concentration ratios were determined for NBUP/BUP, MOR/6-AM and EDDP/MET and could be helpful as indicators of blood external contamination.

A Systematic Review of Metabolite-to-Drug Ratios of Pharmaceuticals in Hair for Forensic Investigations

After ingestion, consumed drugs and their metabolites are incorporated into hair, which has a long detection window, ranging up to months. Therefore, in addition to conventional blood and urine analyses, hair analysis can provide useful information on long-term drug exposure. Meta-bolite-to-drug (MD) ratios are helpful in interpreting hair results, as they provide useful information on drug metabolism and can be used to distinguish drug use from external contamination, which is otherwise a limitation in hair analysis. Despite this, the MD ratios of a wide range of pharmaceuticals have scarcely been explored. This review aims to provide an overview of MD ratios in hair in a range of pharmaceuticals of interest to forensic toxicology, such as antipsychotic drugs, antidepressant drugs, benzodiazepines, common opiates/opioids, etc. The factors influencing the ratio were evaluated. MD ratios of 41 pharmaceuticals were reported from almost 100 studies. MD ratios below 1 were frequently reported, indicating higher concentrations of the parent pharmaceutical than of its metabolite in hair, but wide-ranging MD ratios of the majority of pharmaceuticals were found. Intra- and interindividual differences and compound properties were variables possibly contributing to this. This overview presents guidance for future comparison and evaluation of MD ratios of pharmaceuticals.

Application of Microextraction-Based Techniques for Screening-Controlled Drugs in Forensic Context-A Review

The analysis of controlled drugs in forensic matrices, i.e., urine, blood, plasma, saliva, and hair, is one of the current hot topics in the clinical and toxicological context. The use of microextraction-based approaches has gained considerable notoriety, mainly due to the great simplicity, cost-benefit, and environmental sustainability. For this reason, the application of these innovative techniques has become more relevant than ever in programs for monitoring priority substances such as the main illicit drugs, e.g., opioids, stimulants, cannabinoids, hallucinogens, dissociative drugs, and related compounds. The present contribution aims to make a comprehensive review on the state-of-the art advantages and future trends on the application of microextraction-based techniques for screening-controlled drugs in the forensic context.

Solid-phase microextraction of methadone by using a chitosan nanocomposite incorporated with Polyoxomolibdate nanocluster/Graphene oxide

In the present study, we report on the simple sol-gel preparation of a nanocomposite composed of chitosan/ polyoxometalate /graphene oxide, and its application in the headspace solid-phase microextraction combined with the ion mobility spectrometry for the analysis of methadone in biological matrices. The developed nanocomposite was characterized through the infrared spectroscopy and thermogravimetric analyses. The ternary nanocomposite coating offers good mechanical and thermal stability and high extraction efficiency thanks to its large specific surface. A central composite statistical design was used to study the main variables affecting the extraction efficiency. Afterward, to study the relationship between different input and output variables as well as to identify the optimal operating conditions, response surface methodology was used, whereby a second-order polynomial equation was fit to the experimental data. The optimized extraction conditions were as follows: temperature, 70°C; extraction time, 15 min; and concentration of NaCl, 5%w/v. The detection limit of 0.12 ng/mL was obtained at the optimized extraction conditions, and the calibration plot was linear in the concentration range of 0.30-200 ng/mL. With relatively low limit of detection and good precisions, the proposed method has the potential for the extraction and determination of methadone in biological samples.

Microextraction by Packed Sorbent as a Novel Strategy for Sample Clean-Up in the Determination of Methadone and EDDP in Hair

A microextraction by packed sorbent (MEPS) procedure for rapid concentration of methadone and its primary metabolite (EDDP) in hair samples was developed. The miniaturized approach coupled to gas chromatography with tandem mass spectrometry (GC-MS-MS) was successfully validated. Hair samples (50 mg) were incubated with 1 mL of 1 M sodium hydroxide for 45 min at 50°C, time after which the extract was neutralized by adding 100 μL of 20% formic acid. Subsequently, MEPS was applied using a M1 sorbent (4 mg; 80% C8 and 20% strong cation-exchange (SCX)), first conditioned with three 250-μL cycles of methanol and three 250-μL cycles of 2% formic acid. The extract load occurred with nine 150-μL cycles followed by a washing step involving three 50-μL cycles with 3.36% formic acid. For the elution of the analytes, six 100-μL cycles of 2.36% ammonium hydroxide in methanol were applied. The method was linear from 0.01 to 5 ng/mg, for both compounds, presenting determination coefficients greater than 0.99. Precision and accuracy were in accordance with the statements of international guidelines for method validation. This new miniaturized approach allowed obtaining recoveries ranging from 73 to 109% for methadone and 84 to 110% for EDDP, proving to be an excellent alternative to classic approaches, as well as other miniaturized procedures.

A Systematic Review of Solid-Phase Microextraction Applications in the Forensic Context

Since the introduction in 1990, the solid-phase microextraction (SPME) technology has brought significant progress in many fields of forensic sciences due to the versatility of this fast and solventless alternative to conventional extraction techniques. A systematic review about SPME applications in forensic context from January 1995 to June 2018 was carried out according to systematic review guidelines. The majority of the reviewed articles (40/133) aimed to identify drugs (cannabinoids, cocaine, opiates, amphetamines, simultaneous detection of different drugs of abuse, prescribed drugs); 29 of the 133 articles focused on the investigation of fatalities; 28 of the 133 papers used headspace SPME technique for the identification of markers of chronic alcohol abuse. Sixteen papers involved this technique for the isolation of volatile organic compounds for the human odor profile and 20 concerned forensic applications regarding living people. Solid-phase microextraction was preferably employed in the headspace mode and many kinds of fibers were employed, although polydimethylsiloxane was the most adaptable to many forensic realities. Gas chromatography/mass spectrometry was more frequently used, probably for the well-established coupling with SPME. Most of the papers validated their method to harmonize the scientific approaches of procedures development. Good outcomes are reported on biological material collected from living people as well as on cadaveric samples. The results obtained by most of the studies about alcohol biomarkers on scalp hair have been adopted by the "Society of Hair Testing" to demonstrate abstinence over a pre-defined time period and to assess chronic excessive alcohol consumption.

Solid-phase microextraction of methadone in urine samples by electrochemically co-deposited sol-gel/Cu nanocomposite fiber

Electrochemically co-deposited sol-gel/Cu nanocomposites have been introduced as a novel, simple and single-step technique for preparation of solid-phase microextraction (SPME) coating to extract methadone (MDN) (a synthetic opioid) in urine samples. The porous surface structure of the sol-gel/Cu nanocomposite coating was revealed by scanning electron microscopy. Direct immersion SPME followed by HPLC-UV determination was employed. The factors influencing the SPME procedure, such as the salt content, desorption solvent type, pH and equilibration time, were optimized. The best conditions were obtained with no salt content, acetonitrile as desorption solvent type, pH 9 and 10 min equilibration time. The calibration graphs for urine samples showed good linearity. The detection limit was about 0.2 ng mL^-1 . Also, the novel method for preparation of nanocomposite fiber was compared with previously reported techniques for MDN determination. The results show that the novel nanocomposite fiber has relatively high extraction efficiency.

Dose-concentration relationships of methadone and EDDP in hair of patients on a methadone-maintenance program

After controlled oral administration of D,L-methadone solution (15-260 mg/day) in the context of a methadone-maintenance program, concentrations of methadone and 2-ethylidine-1,5-dimethyl-3,3-diphenyl-l-pyrrolidine (EDDP), in head hair were determined (N=41), using a fully automated headspace solid-phase microextraction procedure in combination with gas chromatography and mass spectrometry (HS-SPME/GC/MS).Methadone was present in all samples in concentrations ranging from 0.25 to 13.29 ng/mg (mean 2.69±0.45 ng/mg). EDDP was also present in every sample in concentrations ranging from 0.05 to 2.17 ng/mg (mean 0.43±0.08). The concentration ratio methadone/EDDP was 7.5±5.7 in the proximal segments, but decreased to 4.8±1.4 in the distal segments. A statistically significant correlation between the intake dose and the methadone and EDDP concentrations in the subjects' hair could be established only in the proximal segments (r=0.913 for methadone and r=0.901 for EDDP), but not in the distal segments. In all, 131 segments analyzed, the correlation coefficient was r=0.760 for methadone and r=0.738 for EDDP. In comparison to the dose-concentration relationship reported in the literature, we found a better correlation with higher correlation coefficients especially in the proximal segments.However, owing to a broad distribution in the correlation between dosage and concentration, the determination of methadone and EDDP in hair holds only limited information about prior methadone administration.

Optimization of solvent bar microextraction combined with gas chromatography for preconcentration and determination of methadone in human urine and plasma samples

In this study, solvent bar microextraction combined with gas chromatography-flame ionization detector (GC-FID) was used for preconcentration and determination of methadone in human body fluids. The target drug was extracted from an aqueous sample with pH 11.5 (source phase) into an organic extracting solvent (1-Undecanol) located inside the pores and lumen of a polypropylene hollow fiber as a receiving phase. To obtain high extraction efficiency, the effect of different variables on the extraction efficiency was studied using an experimental design. The variables of interest were the organic phase type, source phase pH, ionic strength, stirring rate, extraction time, concentration of Triton X-100, and extraction temperature, which were first investigated by Plackett-Burman design and subsequently by central composite design (CCD). So that the optimum experimental condition was obtained when the sodium chloride concentration was 5% (w/v); stirring rate, 700 rpm; extraction temperature, 20 °C; extraction time, 45 min and pH of the aqueous sample, 11.5. Under the optimized conditions, the preconcentration factors were between 275 and 300. The calibration curves were linear in the concentration range of 10-1500 μg L(-1). The limits of detection (LODs) were 2.7-7 and relative standard deviations (RSDs) of the proposed method were 5.9-7.3%. Ultimately, the applicability of the current method was evaluated by the extraction and determination of methadone in different biological samples.

Mechanism-based inactivation of cytochrome P450 2B6 by methadone through destruction of prosthetic heme

Methadone is a μ-opioid receptor agonist widely used in the treatment of narcotic addiction and chronic pain conditions. Methadone is metabolized predominantly in the liver by cytochromes P450 to its pharmacologically inactive primary metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine. Initial in vitro data suggested that CYP3A4 is the major isoform responsible for the in vivo clearance of methadone in humans. However, recent clinical data have indicated that CYP2B6 is actually the major isoform responsible for methadone metabolism and clearance in vivo. In this study, methadone was shown to act as a mechanism-based inactivator of CYP2B6. Methadone inactivates CYP2B6 in a time-, concentration-, and NADPH-dependent manner with a K(I) = 10.0 μM and k(inact) = 0.027 min⁻¹. The loss of CYP2B6 activity in the presence of methadone and NADPH occurred with concomitant loss of the reduced CO spectrum of the P450. Moreover, there was good correlation between the loss of CYP2B6 activity and the loss of the CO-binding spectrum. High-performance liquid chromatography analysis of the native heme of the inactivated CYP2B6 demonstrated that approximately 75% loss of heme was accompanied by comparable inactivation of CYP2B6. Liquid chromatography-mass spectrometry analysis did not reveal the formation of a protein adduct during the inactivation. The evidence strongly suggests that destruction of prosthetic heme is the underlying mechanism leading to the inactivation of CYP2B6 by methadone.

Methadone and metabolites in hair of methadone-assisted pregnant women and their infants

INTRODUCTION

Methadone is the recommended pharmacotherapy for opioid-dependent pregnant women. The primary aims of this study were to determine whether a dose-concentration relationship exists between cumulative maternal methadone dose, methadone and metabolite concentrations in maternal hair during pregnancy and whether maternal hair methadone and metabolite concentrations predict neonatal outcomes.

MATERIALS AND METHODS

Hair specimens were collected monthly from opioid-dependent mothers enrolled in methadone treatment and 4 of their infants. Hair specimens were segmented (3 cm), washed (maternal hair only), and analyzed for methadone, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), and 2-ethyl-5-methyl-3,3-diphenylpyrroline by liquid chromatography tandem mass spectrometry.

RESULTS

There was large intersubject variability and no dose-concentration relationship for cumulative methadone dose and methadone, EDDP, 2-ethyl-5-methyl-3,3-diphenylpyrroline, or total concentrations in hair. For individual women, a positive trend was noted for cumulative methadone dose and methadone and EDDP concentrations in hair. There was a positive linear trend for cumulative methadone dose and EDDP/methadone ratio in maternal hair, perhaps reflecting methadone's induction of its own metabolism. Maternal methadone concentrations were higher than those in infant hair, and infant EDDP hair concentrations were higher than those in maternal hair. Maternal methadone dose, and methadone and EDDP hair concentrations were not correlated with peak infant neonatal abstinence syndrome (NAS) scores, days to peak NAS, duration of NAS, time to NAS onset, birth length, head circumference, or amount of neonatal morphine pharmacotherapy. Maternal cumulative third trimester methadone dose was positively correlated with infant birth weight.

CONCLUSIONS

Methadone and EDDP in pregnant women's hair are markers of methadone exposure and do not predict total methadone dose, nor neonatal outcomes from in utero methadone exposure.

Inhibitory action of methadone and its metabolites on erg-mediated K+ current in GH₃ pituitary tumor cells

Methadone (Mtd) is a widely used opioid drug associated with the side effect of hyperprolactinemia. The mechanism of how Mtd induces prolactin secretion remains unclear. The effects of Mtd and its two main metabolites (EDDP: (±)-2-ethyl-1,5-dimethyl-3,3-diphenylpyrrolinium percholarate and EMDP: 2-ethyl-5-methyl-3,3-dipnehyl-1-pyrroline) on ion currents were investigated in GH₃ pituitary tumor cells. Hyperpolarization-elicited K+ currents in GH₃ cells bathed in a high-K(+), Ca(2+)-free solution were studied to evaluate the effects of Mtd and other related compounds on the ether-à-go-go-related-gene (erg) K(+) current (I(K(erg))). Mtd suppressed the amplitude of I(K(erg)) in a concentration-dependent manner with an IC(50) value of 10.4 μM. With the aid of a minimal binding scheme, the inhibitory action of Mtd on I(K(erg)) was estimated with a dissociation constant of 8.2 μM. Mtd tended to increase the rate of I(K(erg)) deactivation in a voltage-dependent fashion. EDDP (10 μM) had no effect on I(K(erg)), while EMDP (10μM) slightly suppressed it. In GH₃ cells incubated with naloxone (30 μM), the Mtd-induced inhibition of I(K(erg)) remained unaltered. Under cell-attached voltage-clamp recordings, Mtd increased the frequency of spontaneous action currents with no change in current amplitude. Similarly, Mtd can suppress I(K(erg)) in differentiated NG108-15 cells; dynorphin A(1-13) did not reverse Mtd-induced inhibition of I(K(erg)). This study shows that Mtd has a depressant effect on I(K(erg)), and suggests its ability to affect membrane excitability and prolactin secretion. The cyclization of Mtd, in which EDDP and EMDP are formed, tends to be critical in removal of the Mtd binding to erg K+ channel.

Quantitative analysis of methadone in human urine samples by microextraction in packed syringe-gas chromatography-mass spectrometry (MEPS-GC-MS)

A method for the simultaneous analysis of methadone in urine samples by microextraction in a packed syringe online with GC-MS (MEPS-GC-MS) is described. The new method reduced the sample handling and the detection limit by two- to seven-fold compared to published methods. Using a quantitation method based on the calculation of analyte concentration by comparison to an internal standard, we were able to measure methadone levels consistent with values reported for healthy individuals. The intra-assay precisions (RSD) of the method using quality control (QC) samples at three different concentration levels were about 11-14% (n = 6). The interassay precisions (RSD) were 11-15% for methadone in urine samples (n = 18). The accuracy varied from 89 to 109% for intra-assay (n = 6), and 97 to 107% for inter-assay (n = 18). The regression correlation coefficients (r(2)) were over 0.99 in all experiments.

Analytical pitfalls in hair testing

This review focuses on possible pitfalls in hair testing procedures. Knowledge of such pitfalls is useful when developing and validating methods, since it can be used to avoid wrong results as well as wrong interpretations of correct results. In recent years, remarkable advances in sensitive and specific analytical techniques have enabled the analysis of drugs in alternative biological specimens such as hair. Modern analytical procedures for the determination of drugs in hair specimens - mainly by gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) - are reviewed and critically discussed. Many tables containing information related to this topic are provided.

Application of solid-phase microextraction in analytical toxicology

Solid-phase microextraction (SPME) is a miniaturized and solvent-free sample preparation technique for chromatographic-spectrometric analysis by which the analytes are extracted from a gaseous or liquid sample by absorption in, or adsorption on, a thin polymer coating fixed to the solid surface of a fiber, inside an injection needle or inside a capillary. In this paper, the present state of practical performance and of applications of SPME to the analysis of blood, urine, oral fluid and hair in clinical and forensic toxicology is reviewed. The commercial coatings for fibers or needles have not essentially changed for many years, but there are interesting laboratory developments, such as conductive polypyrrole coatings for electrochemically controlled SPME of anions or cations and coatings with restricted-access properties for direct extraction from whole blood or immunoaffinity SPME. In-tube SPME uses segments of commercial gas chromatography (GC) capillaries for highly efficient extraction by repeated aspiration-ejection cycles of the liquid sample. It can be easily automated in combination with liquid chromatography but, as it is very sensitive to capillary plugging, it requires completely homogeneous liquid samples. In contrast, fiber-based SPME has not yet been performed automatically in combination with high-performance liquid chromatography. The headspace extractions on fibers or needles (solid-phase dynamic extraction) combined with GC methods are the most advantageous versions of SPME because of very pure extracts and the availability of automatic samplers. Surprisingly, substances with quite high boiling points, such as tricyclic antidepressants or phenothiazines, can be measured by headspace SPME from aqueous samples. The applicability and sensitivity of SPME was essentially extended by in-sample or on-fiber derivatization. The different modes of SPME were applied to analysis of solvents and inhalation narcotics, amphetamines, cocaine and metabolites, cannabinoids, methadone and other opioids, fatty acid ethyl esters as alcohol markers, gamma-hydroxybutyric acid, benzodiazepines, various other therapeutic drugs, pesticides, chemical warfare agents, cyanide, sulfide and metal ions. In general, SPME is routinely used in optimized methods for specific analytes. However, it was shown that it also has some capacity for a general screening by direct immersion into urine samples and for pesticides and other semivolatile substance in the headspace mode.

Simple and sensitive determination of Δ9-tetrahydrocannabinol, cannabidiol and cannabinol in hair by combined silylation, headspace solid phase microextraction and gas chromatography–mass spectrometry

A new method for determination of Delta(9)-tetrahydrocannabinol (THC), cannabidiol (CBD) and cannabinol (CBN) in hair based on alkaline hair hydrolysis, extraction by iso-octane, combined derivatization with N,O-bis-(trimethylsilyl)-trifluoroacetamide and headspace solid phase microextraction of the extract residue, and gas chromatography-mass spectrometry was developed and evaluated. The limits of detection of the three compounds were 0.01-0.02 ng/mg. The method was routinely applied to more than 250 hair samples. In 77 positive samples, the concentrations ranged from LOD to 4.2 ng/mg for THC (mean 0.49 ng/mg), to 12.1 ng/mg for CBD (mean 0.37 ng/mg) and to 0.85 ng/mg for CBN (mean 0.12 ng/mg) using a sample amount of 30 mg. The frequently observed increase of the segmental drug concentrations from proximal to distal is explained by progressive accumulation in the hair shaft from sebum or side stream smoke.

New trends in hair analysis and scientific demands on validation and technical notes

This review focuses on basic aspects of method development and validation of hair testing procedures. Quality assurance is a major issue in drug testing in hair resulting in new recommendations, validation procedures and inter-laboratory comparisons. Furthermore recent trends in research concerning hair analysis are discussed, namely mechanisms of drug incorporation and retention, novel analytical procedures (especially ones using liquid chromatography-mass spectrometry (LC-MS) and alternative sample preparation techniques like solid-phase microextraction (SPME)), the determination of THC-COOH in hair samples, hair testing in drug-facilitated crimes, enantioselective hair testing procedures and the importance of hair analysis in clinical trials. Hair testing in analytical toxicology is still an area in need of further research.

Methadone as a chemical weapon: two fatal cases involving babies

Methadone is largely used for the substitution management of opiate-dependent individuals but can also be easily found on the black market. The first cases involving repetitive sedation linked to the use of methadone and subsequent death of 2 babies are reported. At the autopsy, no particular morphologic changes were noted except for pulmonary and visceral congestion. There was no evidence of violence, and the pathologist in both cases found no needle marks. Toxicological analyses, as achieved by GC/MS, demonstrated both recent and repetitive methadone exposure. In case 1, a 14-month-old girl was found dead at home. Blood concentrations were 1071 and 148 ng/mL for methadone and EDDP, respectively. Hair (6 cm) tested positive at 1.91 and 0.82 ng/mg for methadone and EDDP, respectively. In case 2, a 5-month-old girl was taken to hospital in a pediatric unit for coma. Antemortem blood analysis demonstrated methadone exposure (142 ng/mL), and the baby was declared dead 12 days after admission. Hair analysis (5 cm) by segmentation was positive for methadone in the range 1.0 (root) to 21.3 ng/mg (end). The death of the babies was attributed to accidental asphyxia ina situation where methadone was considered as a chemical weapon. The mothers, who were the perpetrators in both cases, did not deny the use of methadone as a sedative drug.

Determination of methadone, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine and alprazolam in human plasma by liquid chromatography–electrospray ionization mass spectrometry

A fast liquid chromatographic assay with mass spectrometric detection (LC/MS) has been developed and validated for the simultaneous determination of methadone (MT), its primary metabolite, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) and alprazolam, in human plasma. The extraction procedure was performed with automatic solid phase extraction, and the compounds were separated with a Sunfire column using a gradient mode. Deuterated analogues for all of the analytes of interest were used for quantitation. Limits of detection (LOD) were established between 0.5 and 1 ng/ml. Linearity was obtained over a range of 2-2,000 ng/ml with an average correlation coefficient (R(2)) of >0.99. Intra- and inter-batch coefficients of variation and relative mean errors were less than 10% for all analytes and concentrations. The recoveries were higher than 50.0% in all cases. The method proved to be suitable for evaluation of plasma obtained from patients enrolled in a MT-maintenance program who are frequently treated with alprazolam as a sedative.

State of the art in hair analysis for detection of drug and alcohol abuse

Hair differs from other materials used for toxicological analysis because of its unique ability to serve as a long-term storage of foreign substances with respect to the temporal appearance in blood. Over the last 20 years, hair testing has gained increasing attention and recognition for the retrospective investigation of chronic drug abuse as well as intentional or unintentional poisoning. In this paper, we review the physiological basics of hair growth, mechanisms of substance incorporation, analytical methods, result interpretation and practical applications of hair analysis for drugs and other organic substances. Improved chromatographic-mass spectrometric techniques with increased selectivity and sensitivity and new methods of sample preparation have improved detection limits from the ng/mg range to below pg/mg. These technical advances have substantially enhanced the ability to detect numerous drugs and other poisons in hair. For example, it was possible to detect previous administration of a single very low dose in drug-facilitated crimes. In addition to its potential application in large scale workplace drug testing and driving ability examination, hair analysis is also used for detection of gestational drug exposure, cases of criminal liability of drug addicts, diagnosis of chronic intoxication and in postmortem toxicology. Hair has only limited relevance in therapy compliance control. Fatty acid ethyl esters and ethyl glucuronide in hair have proven to be suitable markers for alcohol abuse. Hair analysis for drugs is, however, not a simple routine procedure and needs substantial guidelines throughout the testing process, i.e., from sample collection to results interpretation.

Surfactant enhanced liquid-phase microextraction of basic drugs of abuse in hair combined with high performance liquid chromatography

The aim of this study was to evaluate the performance of a technique for simultaneous testing of hydrophilic abuse drugs in hair. The analysis of, codeine and methadone in morphine hair included incubation in methanol (5h, 50 degrees C), Surfactant enhanced liquid-phase microextraction (SE-LPME) and HPLC analysis. This study has demonstrated that SE-LPME constitute a real alternative to the other liquid-phase microextraction methods, for pre-concentration and extraction of hydrophilic drugs in biological samples and has shown the advantages of these optimized methodologies over the traditional microextraction techniques. For these drugs recoveries in the range of 57.5-93.7 were obtained from hair. The drugs were enriched by a factor of 61-128 during SE-LPME. Linearity (r2, 0.9982-0.9997) was obtained in the range of 50-500 microg/l for morphine and 10-500 microg/l for codeine and methadone.

Determination of cocaine, benzoylecgonine and cocaethylene in human hair by solid-phase microextraction and gas chromatography-mass spectrometry

The present work describes a highly precise and sensitive method developed to detect cocaine (COC), benzoylecgonine (BE, its main metabolite) and cocaethylene (CE, transesterification product of the coingestion of COC with ethanol) in human head hair samples. The method was based on an alkylchloroformate derivatization of benzoylecgonine and the extraction of the analytes by solid-phase microextraction (SPME). Gas chromatography-mass spectrometry (GC-MS) was used to identify and quantify the analytes in selected ion monitoring mode (SIM). The limits of quantification and detection (LOQ and LOD) were: 0.1 ng/mg for COC and CE, and 0.5 ng/mg for BE. Good inter- and intra-assay precision was observed. The dynamic range of the assay was 0.1-50 ng/mg. The method is not time consuming and was shown to be easy to perform.

Neonatal hair analysis contribution to establishing a gestational drug exposure profile and predicting a withdrawal syndrome

Recently, interest in hair analysis in such fields as drug abuse, driving, or for clinical purposes (determination of drug-exposed neonates especially) has grown because of the highly sensitive method of detection (GC-MS) that can now be applied. Neonates born to drug-addicted mothers can suffer from neonatal withdrawal syndrome (NWS), which requires morphine treatment in its severe forms. To assess and measure toxicologic factors predicting the appearance and the severity of this syndrome, matrices such as urine, meconium, and hair are necessary. Cannabinoids, opiates, cocaine (and its metabolites), and methadone in particular were determined in the various matrices collected in 17 mother/neonate pairs. An immunologic screening method was used, and quantification was achieved with GC-MS. In spite of some bias (color, length, race) that might hinder an accurate interpretation, the results of hair analysis makes it possible to confirm a fetal drug exposure and to reinforce the diagnosis of the NWS observed, particularly when results obtained in other matrices are negative. Hair analysis contributes to our ability to predict a NWS.

Application of tandem mass spectrometry combined with gas chromatography and headspace solid-phase dynamic extraction for the determination of drugs of abuse in hair samples

A new method combination, headspace solid-phase dynamic extraction coupled with gas chromatography/tandem mass spectrometry (HS-SPDE/GC/MS/MS), is introduced to determine drugs of abuse in hair samples. This highly automated procedure utilizes SPDE for pre-concentration and on-coating derivatization as well as GC and triple quadrupole MS/MS for selective and sensitive detection. All these steps, apart from washing and cutting of the hair samples, are performed without manual intervention on a robot-like autosampler.SPDE is a solventless extraction technique related to solid-phase microextraction (SPME). The analytes are absorbed from the sample headspace directly into a hollow needle with an internal coating of polydimethylsiloxane by repeated aspirate/dispense cycles.The HS-SPDE/GC/MS/MS procedure was applied to the analysis of methadone, the trimethylsilyl derivatives of cannabinoids and the trifluoroacetyl derivatives of amphetamines and designer drugs. The method was shown to be sensitive with detection limits between 6 and 52 pg/mg hair matrix and precision between 0.4 and 7.8% by the use of an internal standard technique. Linearity was obtained from 0.1-20 ng/mg with coefficients of correlation between 0.995 and 0.999. Compared with conventional methods of hair analysis, HS-SPDE/GC/MS/MS is easier to use, substantially faster, with the degree of sensitivity and reproducibility demanded in clinical and forensic toxicology. The main advantage of the SPDE technique in relation to SPME is the robustness of the capillary.

Automated headspace solid-phase microextraction and capillary gas chromatography analysis of ethanol in postmortem specimens

Solid-phase microextraction (SPME) is a relatively new solventless sample preparation technique that allows simultaneous sampling, extraction, pre-concentration, and introduction of analytes from a sample matrix in a single procedure. This methodology has been used for the analysis of several drugs of forensic toxicology interest including volatile compounds. This paper describes a methodology for analysis of ethanol and other volatile compounds using automatic headspace solid-phase microextraction (HS-SPME) and capillary gas chromatography in postmortem specimens. The methodology was initially developed using standard solutions of acetaldehyde, acetone, methanol, and ethanol. Isobutanol was used as internal standard. Postmortem samples of blood, urine, and vitreous humor were obtained during medico-legal autopsies. To date, there are no published paper regarding alcohol analysis in vitreous humor specimens using HS-SPME and limited literature analyzing blood and urine samples. HS-SPME analysis showed that, under optimized conditions, ethanol and isobutanol (internal standard) were well-separated from other volatile compounds such as acetaldehyde, acetone, and methanol considered to be potential interferents in ethanol analysis. The calibration curves for each volatile compound demonstrated good linearity throughout the concentration range from 0.001 to 1.0 g/dl and the detection limit of ethanol in the studied specimens was approximately 0.0001 g/dl.

Role of gas chromatography-mass spectrometry with negative ion chemical ionization in clinical and forensic toxicology, doping control, and biomonitoring

This paper reviews procedures for the detection or quantification of drugs, pesticides, pollutants, and/or their metabolites relevant to clinical and forensic toxicology, doping control, or biomonitoring using gas chromatography-mass spectrometry with negative ion chemical ionization (GC-MS-NICI). Papers written in English between 1995 and 2000 are reviewed. Procedures are included for the analysis of the following halogen-containing or derivatizable compounds in common biosamples, such as whole blood, plasma, or urine, and in alternative matrices such as sweat, hair, bone, or muscle samples of humans or rats: benzodiazepines, cannabinoids, opioids, acetylsalicylic acid, angiotensin-converting enzyme inhibitors, ketoprofen, methylphenidate enantiomers, tegafur, zacopride, anabolic steroids, chlorophenols, chlorpyrifos, hexachlorocyclohexanes, organochlorines, and polychlorinated biphenyls. The principal information on each procedure is summarized in three tables to facilitate the selection of a method suitable for a specific analytic problem.

Analysis of fatty acid ethyl esters in hair as possible markers of chronically elevated alcohol consumption by headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS)

Fatty acid ethyl esters (FAEE) are products of the nonoxidative ethanol metabolism, which are known to be detectable in blood only about 24h after the last alcohol intake. After deposition in hair they should be suitable long-term markers of chronically elevated alcohol consumption. Therefore, a method for the analysis of ethyl myristate, ethyl palmitate, ethyl oleate and ethyl stearate from hair was developed based on the extraction of the hair sample by a dimethylsulphoxide (DMSO)/n-hexane mixture, separation and evaporation of the n-hexane phase and application of headspace solid-phase microextraction (HS-SPME) in combination with gas chromatography-mass spectrometry (GC-MS) to the extract. For use as internal standards, the corresponding D(5)-ethyl esters were prepared. The HS-SPME/GC-MS measurements were automatically performed using a multi-purpose sampler. The detection limits of the FAEE were between 0.01 and 0.04ng/mg and the reproducibility was between 3.5 and 16%. By application of the method to hair samples of 21 fatalities with known heavy alcohol abuse 0.045-2.4ng/mg ethyl myristate, 0.35-13.5ng/mg ethyl palmitate, 0.25-7.7ng/mg ethyl oleate and 0.05-3.85ng/mg ethyl stearate were measured. For social drinkers (30-60g ethanol per week), the concentrations were about one order of magnitude smaller. For 10 teetotalers negative results or traces of ethyl palmitate were found. It was shown by supplementary investigations in single cases that FAEE are also present in sebum, that there is no strong difference in their concentrations between pubic, chest and scalp hair, and that they are detectable in hair segments after a 2 months period of abstinence. From the results follows that the measurement of FAEE concentrations in hair is a useful way for a retrospective detection of alcohol abuse.