Abuse In Urine Samples Research Articles

Matrix-Compatible Solid-Phase Microextraction Pin Coupled Directly to Mass Spectrometry using Probe Electrospray Ionization.

A solid-phase microextraction (SPME) pin device with a biocompatible coating on the tip was developed for direct coupling to mass spectrometry (MS) via a vertical dipping-and-spray strategy using an automated probe electrospray ionization (PESI) interface. The developed method provides superior sensitivity compared to standard PESI-MS due to the enrichment effects of SPME and the significant increase in the volume of sample and/or solvent collected during dipping due to the SPME pin's notably larger size. The tips of the SPME pins were coated with a biocompatible coating consisting of small sorbent particles embedded into a polyacrylonitrile (PAN) binder. This coating enables the extraction of small molecules, while preventing larger molecules such as tissue fragments, proteins, and cell matter from coming into the sorbent. The developed SPME pin-PESI-MS method also features much lower matrix effects compared to PESI-MS for the analysis of complex biology samples. When applied for the analysis of 8 drugs of abuse in urine samples, the SPME pin-PESI-MS method provided good linearity (R2 ≥ 0.9997), high sensitivity with limits of detection between 0.003 to 0.03 ng/mL, and good reproducibility with RSD% ≤ 6%. The vertical design of the SPME-PESI-MS direct-coupling interface allows the potential fully automation of the system using a conventional autosampler.

High resolution, high accuracy non-targeted LC-HR-MS/MS dried urine spot screening for drug of abuse testing

Screening for drugs of abuse in urine samples collected during roadside traffic testing is common practice in Switzerland. The use of an onsite rapid test for the detection of drugs and their metabolites is generally limited by a restricted panel of detectable drugs or substance classes (e.g. buprenorphine, benzodiazepines, cocaine, EDDP, morphine or opiates) with limited sensitivity and specificity. To improve the screening for legal and illegal drugs, the already collected urine sample typically undergoes an additional screening routine in a forensic laboratory. By using dried urine spots (DUS), sample handling, shipment, and storage could be substantially simplified, when compared to the sample handling of liquid urine. To prepare a DUS, the driver's urine is pipetted on a prepared paper card. The subsequent drying of the specimen, starting immediately after its collection, can prevent the post-sampling formation or degradation of substances (e.g. caused by bacteria). Furthermore, the DUS can be stored and shipped at ambient temperature and need no cooling or freezing. To evaluate the potential of DUS screening, 17 authentic urine samples containing multiple substances, were pipetted (10 μL) onto Autocollect TFN filter paper cards (Ahlstrom, France). After drying, the DUS cards were extracted (6 mm Ø extraction head) into glass vials with an insert (100 μL, methanol/water, 70/30, v/v), using a fully automated CAMAG DBS-MS 500 HCT autosampler in combination with a PAL RSI 3 robot. Subsequently, the prepared extracts were analyzed on a Sciex 5600 TOF instrument using a non-targeted screening and library searching approach. Thereby, 1 μL of the extract was injected onto a Kinetex C8 column and a ballistic gradient was used (mobile phase A: H2O+ 0.1% HCOOH, mobile phase b: MeCN + 0.1% HCOOH). A run time of 15 minutes was applied. To evaluate the performance of DUS, the screening results were compared to the analysis of the same urine sample in liquid form, using the same method on the same LC-MS instrument (injection of 1 μL of a 1/10 diluted urine). More than 50 different legal and illegal drugs were successfully identified within the investigated 17 urine samples using the DUS screening approach: 6-MAM, alprazolam, amoxicillin, amphetamine + metabolite, bisoprolol, bupropion + metabolite, caffeine + metabolites, carbamazepine + metabolites, citalopram + metabolite, cocaethylene, cocaine + BE + EME, codeine + metabolite, fentanyl, gabapentin, ketamine + metabolites, lacosamide, lamotrigine, levetiracetam, lidocaine, lorazepam + metabolite, losartan, metamizole-metabolites, metformin, methadone + EDDP, methylphendiate, metoclopramide, metoprolol, midazolam + metabolite, morphine + metabolite, nicotine + cotinine, ondansetron, oxazepam, paracetamol + metabolites, phenytoin, pregabalin + metabolite, promazine, propranolol, quetiapine + metabolites, sildenafil + metabolite, THC-COOH, torasemide, tramadol + metabolite, tranexamic acid, trazodone-metabolite, trimipramine + metabolites, venlafaxine-metabolite, zolpidem + metabolite. When compared to the analysis of liquid urine, the following compounds could not be identified: 2× nicotine, 1× promazine, 1× THC-COOH. Overall, 96% of the target substances that have been detected in liquid urine were identified correctly using the DUS approach. The DUS contain 10 μL of urine, therefore the signal intensity compared to liquid urine analysis, where we used 30 μL, is on average 68% lower. In most cases all substances were identified correctly using the DUS screening approach. Because of lower signal intensities for the DUS in one case of nicotine, promazine and THC-COOH were not properly identified. DUS Screening offers a simple, cost-effective and easier sample handling alternative to the traditional use of liquid urine. Based on the obtained results, a pilot study has been initiated (during roadside traffic control by the local police) in order to verify the usability in the forensic workflow.

Analysis of illicit pills and drugs of abuse in urine samples using a 3D-printed open port probe hyphenated with differential mobility spectrometry-mass spectrometry.

The present work describes the application of an in-house developed 3D-printed open port probe (3DP-OPP) with differential ion mobility spectrometry (DMS) mass spectrometry. Targeted quantitative analysis in urine was performed with a triple quadrupole mass spectrometer in the selected reaction monitoring mode (OPP-DMS-SRM/MS) and illicit pill screening using data independent acquisition (OPP-DMS-SWATH/MS). The combination of compensation voltage (CoV) scanning in DMS using modifiers with SWATH/MS acquisition for MS/MS spectrum generation enabled the differentiation of isobaric signals with a large dynamic range and enhance the information contained in the screening of illicit ecstasy pills. As for any direct MS introduction technique where no chromatographic separation is applied DMS with acetonitrile as a modifier allows the separation of cocaine and tramadol, and their isomeric metabolites in urine samples. Quantitative application using OPP-DMS-SRM/MS is presented without the need for sample preparation with a lower limit of quantification at 10-25 ng mL-1 for the analytes and less than 40 seconds for sample to sample analysis.

Enantiodetermination of R,S-3,4-methylenedioxypyrovalerone in urine samples by high pressure in-line solid-phase extraction capillary electrophoresis-mass spectrometry

This study presents for the first time an in-line solid-phase extraction capillary electrophoresis-mass spectrometry (SPE-CE-MS) method for the enantiodetermination of drugs of abuse in urine samples. The enantioseparation of R,S-3,4-methylenedioxypyrovalerone (R,S-MDPV) was achieved with a 10 mM ammonium acetate BGE (pH 7) that contained 0.5% (m/v) of sulphated-α-CD as chiral selector. At these pH conditions, this CD was negatively charged, which prevented its entrance into the mass spectrometer since it migrates in the opposite direction. To improve sensitivity, an in-line SPE-CE-MS method using high pressure for sample introduction (i.e. 20 min at 3 bars) was developed. Furthermore, the conditioning procedure and the first part of the electrophoretic separation were performed by switching off the nebulizer gas and the ionization source voltage to avoid non-volatile contaminant arrival into the mass spectrometer. The developed methodology was validated by analyzing urine samples, which required a very simple liquid-liquid extraction (LLE) sample pretreatment. Linearity ranged from 30 to 250 ng mL−1, limit of detection (LOD) was 10 ng mL−1, relative standard deviation (RSD) values were below 10.5% in terms of intra-day and inter-day precision and the relative error values were below 9% for peak areas accuracy.

Comparison of centrifugation and solid phase extraction (SPE) methods of sample preparations in determination of residues of drugs of abuse in urine

Detection of drugs of abuse in urine samples depends on their composition, absorption,distribution, physical and chemical properties, concentrations, elimination properties, and thetechniques employed. This study compared the performance of centrifugation and solid phaseextraction (SPE) methods in the determination of levels of drugs of abuse and their metabolites inurine samples collected from drug abusers. Analysis was performed using liquid chromatographytandemmass spectrometry (LC-MS-MS). Calibration was done using both internal and externalstandards. The recovery values were generally greater in centrifugation method than in SPEmethod, but the recoveries in both methods were within an acceptable range. Linearity values (R2)ranged from 0.9789 to 0.9944 with an average of 0.99. The LOD and LOQ values weresatisfactory. The concentrations of 6-monoacetylmorphine (6-MAM), morphine and cocaine wereup to 3.37, 4.21 and 0.03 μg/mL, respectively in samples prepared by centrifugation method, whilein samples prepared by SPE method were up to 6.67, 6.66 and 0.13 μg/mL, respectively. The meanconcentrations and detection frequencies of 6-MAM and morphine were higher in samplesprepared by centrifugation method than those of SPE method. Cocaine had the same meanconcentrations and detection frequencies in samples prepared by both methods. There were nosignificant differences in the concentrations of the drugs of abuse between the samples prepared bycentrifugation and SPE methods, although the levels of the drugs in the samples prepared bycentrifugation method were slightly greater than those prepared by SPE method.

Determination of ring-substituted amphetamines through automated online hollow fiber liquid-phase microextraction-liquid chromatography

The present paper describes an original method for the online preconcentration and analysis of ring-substituted amphetamines in urine samples, used on the integration of robot-assisted hollow fiber liquid-phase microextraction (HF-LPME), high-performance liquid chromatography (HPLC), and fluorescence detection (FLD). A lab-made autosampler, actuating a 100-μL syringe and equipped with a three-way solenoid microvalve, allowed the acceptor phase to flow through and be withdrawn from the lumen fiber, enabling the automated online transference of the enriched acceptor phase for chromatographic analysis, through a six-port switching valve. The developed online HF-LPME-LC/FLD method demonstrated high analytical throughput and confidence, facilitating the efficient extraction and determination of the target analytes, with minimal solvent consumption and sample manipulation, in a straightforward way. Sample cleanup, analyte uptake, and analysis were carried out in 14.5 min. Under optimal conditions, automated online HF-LPME showed excellent linearity, precision, and trueness, obtaining intraday RSDs between 2.9 and 9.2% (n = 6) and interday RSDs between 5.3 and 9.3% (n = 6). Enrichment factors (EFs) ranged between 14.2 and 15.7, extraction recoveries (ERs) ranged between 17.7 and 19.5%, and the limits of detection (S/N = 3) were 2.0, 3.0, and 3.0 μg L-1 for MDA, MDMA, and MDEA, respectively. The method proved to be an effortless, rapid, reliable, and environment-friendly approach for the determination of drug abuse in urine samples. Graphical abstract.

Prevalence of drugs of abuse found in testing of illicit drug seizures and urinalysis of selected population in Hong Kong

The study investigates the prevalence of drugs of abuse detected from 2011 to 2015 through (i) forensic drug testing of illicit drug seizures from law enforcement agencies; and (ii) analysis of common drugs of abuse in urine samples obtained from offenders/probationers under mandatory drug-use surveillance programmes. Under the selected drug testing groups, there were an average of 5334 cases/year of illicit drug seizures examined and 28,438 samples/year requiring drugs of abuse analysis in urine, from 2011 to 2015. The drug positive rates for urinalysis in the selected population group (i.e., offenders/probationers requiring mandatory drug testing) were steady with an average of about 22%. The ratio of single drug use to more than one drug was about 4:1, showing predominant use of single drug. Ketamine, methamphetamine (MA) and heroin were the three most commonly encountered abused drugs through laboratory testing. During the period, identification of ketamine was shown to decline continuously in both illicit drug testing and urinalysis while there was substantial increase in detection of MA. A rising trend was noted for cases identified with new psychotropic substances (NPS) in illicit drug seizures although NPS cases contributed to a small proportion of overall drug seizure cases examined (<5%) in the study period. A total of 47 substances classified as NPS were encountered with cathinones, either synthetic or plant-based, contributed to the majority of NPS cases (˜77%) followed by synthetic cannabinoids and phenethylamines.

Prevalence Of Drug Abuse Among Drivers In Minia Governorate

Background: In Egypt, drug abuse is one of the dangerous problems that threaten the young adults and worry the government. One of the most essential points for drug abusers are those dealing with the transportation and driving on the road because substance abuse increases the possibility of death after road accidents. Subjects & methods: The study was conducted in Minia Governorate in order to determine the prevalence of drug abuse in urine samples of drivers. The screening test was done with the co-operation of health ministry and ministry of interior. The study was conducted in Minia Governorate from 6th September 2014 till 5th February 2015 on 3338 male drivers aged (16-70) years old. Results: The test was positive in 473 drivers (14.2%). The highest percentage of drug abuse was observed among age group (18-30) years old. The prevalence of tramadol was 7.2%, Tetrahydrocannabinol (THC) 3.6%, opium 0.15%, benzodiazepines 0.03%, combined tramadol and THC 2.9%, tramadol and opium 0.1%, tramadol and benzodiazepines 0.03%, combined tramadol, THC and opium 0.2%. According to vehicle type; taxi and microbus drivers had the highest percentage of drug abuse followed by private cars then truck drivers. There is decrease in number of positive cases among the period of study from September till February. Conclusion: The highest percentage of drug abuse is among age group (18-30) years old. Tramadol is the most common drug of abuse among drivers in Minia Governorate.

Rapid analysis of fentanyls and other novel psychoactive substances in substance use disorder patient urine using paper spray mass spectrometry.

Drug overdose deaths due to fentanyls and other novel psychoactive substances (NPS) are on the rise. The higher potencies of fentanyl analogs compared with morphine require new technologies to identify and quantitate NPS. Paper spray tandem mass spectrometry (MS/MS) and high-resolution mass spectrometry were used to identify and measure fentanyl analogs as well as common drugs of abuse in urine samples from substance use disorder clinics. Ten-microliter urine samples were deposited directly on paper spray cartridges previously loaded with internal standards, dried, and analyzed with no other sample treatment. Quantitative results were obtained using MS/MS. Individual drugs were identified using high-resolution accurate mass spectrometry, and confirmed by data-dependent MS/MS. Calibration curves in urine were linear over a range of 0.5-50ng/mL with R2 of 0.99 or better for eight representative fentanyl analogs. Cartridges preloaded with internal standards demonstrated satisfactory quantitative results compared with LC/MS. Direct identification and confirmation of fentanyl analogs and other common drugs of abuse in urine using high-resolution accurate mass and MS/MS fragmentation were demonstrated at low picogram levels. Paper spray mass spectrometry can reliably identify and quantitate fentanyl analogs and other drugs of abuse in urine. Using paper spray cartridges as collection devices reduces exposure and transportation risks associated with biological fluids. Cartridges preloaded with labeled internal standards can be effective for targeted screening of fentanyl analogs and other drugs of abuse.

Androgen- and estrogen-receptor mediated activities of 4-hydroxytestosterone, 4-hydroxyandrostenedione and their human metabolites in yeast based assays

4-Hydroxyandrost-4-ene-3,17-dione, also named formestane, is an irreversible aromatase inhibitor and therapeutically used as anti-breast cancer medication in post-menopausal women. Currently, no therapeutical indication led to approval of its 17-hydroxylated analog 4-hydroxytestosterone, an anabolic steroid. However, it is currently investigated in a clinical trial for breast cancer. In context with sports doping, aromatase inhibitors are administered to reduce estrogenic side effects of misused anabolic substances or their metabolites. Therefore, both substances are prohibited in sports by the World Anti-Doping Agency (WADA). Analysis of urinary phase I and phase II metabolites showed similar results for both compounds. In the current investigation, 4-hydroxyandrost-4-ene-3,17-dione, 4-hydroxytestosterone and seven of their described urinary metabolites as well as 2α-hydroxyandrostenedione were tested in the yeast androgen screen and the yeast estrogen screen. Androgenic effects were observed for all tested substances, except for one, which showed anti-androgenic properties. With regard to the yeast estrogen screen, estrogenic effects were observed for only two metabolites at rather high concentrations, while six out of the ten substances tested showed anti-estrogenic properties. In terms of the strong androgenic effect observed for 4-hydroxytestosterone (10−8 M), 4-hydroxyandrost-4-ene-3,17-dione (10−8 M) and two more urinary metabolites, the yeast androgen assay may also be used to trace abuse in urine samples.

Stability of Drugs of Abuse in Urine Samples at Room Temperature by Use of a Salts Mixture.

It has long been recognized that ensuring analyte stability is of crucial importance in the use of any quantitative bioanalytical method. As analyses are usually not performed directly after collection of the biological samples, but after these have been processed and stored, it is essential that analyte stability can be maintained at storage conditions to ensure that the obtained concentration results adequately reflect those directly after sampling. The conservation of urine samples in refrigerated/ frozen conditions is strongly recommended; but not always feasible. The aim of this study was to assess the stability of some well-known drugs of abuse methamphetamine (MA), 11-nor-9-carboxy-Δ9- tetrahydrocannabinol (THC-COOH), benzoylecgonine (BE), and morphine (MOR) in urine samples kept at room temperature by adding a salt mixture (sodium citrate, sodium ascorbate, borax). Two different urine samples were prepared with and without salt mixture, stored at room temperature and then analyzed by gas chromatography-mass spectrometry at 0, 1, 7, 15, and 30 days after collection/preparation to look for eventual analyte degradation. Methamphetamine showed no significant changes with respect to the time of collection/ preparation (T0) up to 7 days later (T7), with or without salt mixture addiction. Then a significant degradation occurred in both salted and non salted urine. BE decrease was observed starting from day 1 after sample collection in salted and not salted samples, respectively. Salt addition seemed to reduce at least the initial BE degradation, with a significant difference (p<0.001) at 7 and 15 days of storage. However, the degradation was not more prevented in salted samples at 30 days of storage. A 20% decrease of MOR concentration was observed starting from day 1 after collection/preparation, both in salted and not salted samples with no subsequent decrease. With regard to THCCOOH, a significant decrease was observed starting from 7 days after collection/preparation, with of without adding the salt mixture. However, when comparing salted versus non salted samples at each time point, a statistically significant difference was observed at 7 and 30 days of storage. The results obtained indicate that the degradation of MA, THC-COOH and BE in urine samples kept at room temperature can be slowed by the addition of the salt mixture, whereas it seems to be ineffective in samples containing MOR. This evidence has to be taken into account, in the eventuality of using salted urine to prevent in a certain extent abuse of above-reported drugs of abuse.

Capillary electrophoresis combined in-line with solid-phase extraction using magnetic particles as new adsorbents for the determination of drugs of abuse in human urine.

A simple approach is presented based on the in-line coupling between magnetic particles-based SPE and CE. Silica-coated iron oxide particles functionalized with C18 were successfully synthesized and used as a reverse-phase sorbent for in-line SPE-CE. Magnets were used to locally immobilize these sorbents inside the capillary. Four drugs of abuse were preconcentrated and determined in urine samples using the developed method with a simple pretreatment procedure based on LLE. Several parameters affecting the preconcentration were evaluated. The obtained results show that this strategy enhanced detection sensitivity in the range of 125-700-fold compared with CE without preconcentration. The developed method provides LODs (S/N = 3) for standard samples in the range of 0.5-20 ng/mL with satisfactory analytical precision, in both intraday and day-to-day experiments (RSDs <20%). The LODs (S/N = 3) reached for urine samples were in the range of 20-50 ng/mL. Relative recoveries greater than 75.9% were obtained. The established method has been applied to the analysis of drugs of abuse in urine samples from drug abusers.

Simultaneous Screening of 177 Drugs of Abuse in Urine Using Ultra-performance Liquid Chromatography with Tandem Mass Spectrometry in Drug-intoxicated Patients

ObjectiveThe demand for rapid and broad clinical toxicology screening methods to identify drugs of abuse and medicinal drugs is increasing steadily. Liquid chromatography-tandem mass spectrometry (LC-TMS) is increasingly used to screen for drugs of abuse and to identify a wide range of drugs and metabolites in clinical samples. We revised a high-throughput and rapid ultra-performance (UP) LC-TMS method for simultaneous screening of 177 of the most prevalent medicinal drugs and drugs of abuse in urine and validated the quality of performance using system suitability mixture (SSM) and quality control (QC) materials.MethodsWe assessed the limits of detection (LOD) using high concentrations of the test substances. The method was applied to 473 urine samples obtained from patients intoxicated with drugs who visited the emergency center.ResultsThe retention time, peak area, and total ion chromatogram of the SSM and QC materials were within the acceptance criteria of the pre-defined acceptance interval. The LODs were <62 ng/ml for 12 commonly encountered drugs. In total, 418 patients (88.4%) tested positive for one or more medicinal drugs or drugs of abuse. Twenty-eight drugs were detected over ten times; the most commonly detected were zolpidem, ephedrine, paracetamol, and chlorpheniramine.ConclusionThe UPLC-TMS method provided excellent performance for simultaneous screening of a large number of the drugs of abuse in urine samples. We conclude that this robust technique is useful for screening for a large number of drugs and for rapid screening of the most commonly encountered substances in emergency cases.

A high-sensitivity ultra-high performance liquid chromatography/high-resolution time-of-flight mass spectrometry (UHPLC-HR-TOFMS) method for screening synthetic cannabinoids and other drugs of abuse in urine

The continuing emergence of designer drugs imposes high demands on the scope and sensitivity of toxicological drug screening procedures. An ultra-high performance liquid chromatography/high-resolution time-of-flight mass spectrometry (UHPLC-HR-TOFMS) method was developed for screening and simultaneous confirmation of both designer drugs and other drugs of abuse in urine samples in a single run. The method covered selected synthetic cannabinoids and cathinones, amphetamines, natural cannabinoids, opioids, cocaine and other important drugs of abuse, together with their main urinary metabolites. The database consisted of 277 compounds with molecular formula and exact monoisotopic mass; retention time was included for 192 compounds, and primary and secondary qualifier ion exact mass for 191 and 95 compounds, respectively. Following a solid-phase extraction, separation was performed by UHPLC and mass analysis by HR-TOFMS. MS, and broad-band collision-induced dissociation data were acquired at m/z range 50-700. Compound identification was based on a reverse database search with acceptance criteria for retention time, precursor ion mass accuracy, isotopic pattern and abundance of qualifier ions. Mass resolving power in spiked urine samples was on average FWHM 23,500 and mass accuracy 0.3 mDa. The mean and median cut-off concentrations determined for 75 compounds were 4.2 and 1 ng/mL, respectively. The range of cut-off concentrations for synthetic cannabinoids was 0.2-60 ng/mL and for cathinones 0.7-15 ng/mL. The method proved to combine high sensitivity and a wide scope in a manner not previously reported in drugs of abuse screening. The method's feasibility was demonstrated with 50 authentic urine samples.

Highly sensitive capillary electrophoresis-mass spectrometry for rapid screening and accurate quantitation of drugs of abuse in urine

The combination of capillary electrophoresis (CE) and mass spectrometry (MS) is particularly well adapted to bioanalysis due to its high separation efficiency, selectivity, and sensitivity; its short analytical time; and its low solvent and sample consumption. For clinical and forensic toxicology, a two-step analysis is usually performed: first, a screening step for compound identification, and second, confirmation and/or accurate quantitation in cases of presumed positive results. In this study, a fast and sensitive CE-MS workflow was developed for the screening and quantitation of drugs of abuse in urine samples. A CE with a time-of-flight MS (CE-TOF/MS) screening method was developed using a simple urine dilution and on-line sample preconcentration with pH-mediated stacking. The sample stacking allowed for a high loading capacity (20.5% of the capillary length), leading to limits of detection as low as 2ngmL−1 for drugs of abuse. Compound quantitation of positive samples was performed by CE-MS/MS with a triple quadrupole MS equipped with an adapted triple-tube sprayer and an electrospray ionization (ESI) source. The CE-ESI-MS/MS method was validated for two model compounds, cocaine (COC) and methadone (MTD), according to the Guidance of the Food and Drug Administration. The quantitative performance was evaluated for selectivity, response function, the lower limit of quantitation, trueness, precision, and accuracy. COC and MTD detection in urine samples was determined to be accurate over the range of 10–1000ngmL−1 and 21–1000ngmL−1, respectively.

In-line solid-phase extraction–capillary electrophoresis coupled with mass spectrometry for determination of drugs of abuse in human urine

In-line solid-phase extraction-capillary electrophoresis coupled with mass spectrometric detection (SPE-CE-MS) has been used for determination of 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), codeine (COD), hydrocodeine (HCOD), and 6-acetylmorphine (6AM) in urine. The preconcentration system consists of a small capillary filled with Oasis HLB sorbent and inserted into the inlet section of the electrophoresis capillary. The SPE-CE-MS experimental conditions were optimized as follows: the sample (adjusted to pH6.0) was loaded at 930mbar for 60min, elution was performed with methanol at 50mbar for 35s, 60mmolL(-1) ammonium acetate at pH3.8 was used as running buffer, the separation voltage was 30kV, and the sheath liquid at a flow rate of 5.0μLmin(-1) was isopropanol-water 50:50 (v/v) containing 0.5% acetic acid. Analysis of urine samples spiked with the four drugs and diluted 1:1 (v/v) was studied in the linear range 0.08-10ngmL(-1). Detection limits (LODs) (S/N = 3) were between 0.013 and 0.210ngmL(-1). Repeatability (expressed as relative standard deviation) was below 7.2%. The method developed enables simple and effective determination of these drugs of abuse in urine samples at the levels encountered in toxicology and doping.

Effect of Buprenorphine Dose on Treatment Outcome

The goal of this meta-analysis is to provide evidence based information about proper dosing for buprenorphine maintenance treatment to improve treatment outcome. To be selected for the review and inclusion in the meta-analysis, articles had to be randomized, controlled, or double-blind clinical trials, with buprenorphine as the study drug; the length of buprenorphine maintenance treatment had to be 3 weeks or longer; doses of buprenorphine had to be clearly stated; outcome measures had to include retention rates in buprenorphine treatment; outcome measures had to include illicit opioid use based on analytical determination of drugs of abuse in urine samples as outcome variables; and outcome measures had to include illicit cocaine use based on analytical determination of drugs of abuse in urine samples as outcome variables. Twenty-nine articles were excluded because they did not meet the inclusion criteria. The authors present the results of 21 articles that met inclusion criteria. The higher buprenorphine dose (16–32 mg per day) predicted better retention in treatment compared with the lower dose (less than 16 mg per day) (P = .009, R2 adjusted = 0.40), and the positive urine drug screens for opiates predicted dropping out of treatment (P = .019, R2 Adjusted = 0.40). Retention in treatment predicted less illicit opioid use (P = .033, R2 Adjusted = 0.36), and the positive urine drug screens for cocaine predicted more illicit opioid use (P = .021, R2 Adjusted = 0.36). Strong evidence exists based on 21 randomized clinical trials that the higher buprenorphine dose may improve retention in buprenorphine maintenance treatment.

PH-resistant titania hybrid organic–inorganic coating for stir bar sorptive extraction of drugs of abuse in urine samples followed by high performance liquid chromatography–ultraviolet visible detection

An organic–inorganic hybrid titania-hydroxy-terminated silicone oil (titania-OH-TSO) stir bar coating was prepared by sol–gel method. The extraction performance of titania-OH-TSO coated stir bar was evaluated and compared with poly(dimethysiloxane) (PDMS), poly(dimethysiloxane)–divinylbenzene (PDMS–DVB), poly(dimethysiloxane)–β-cyclodextrin (PDMS–β-CD) and C 18 coated stir bar with five polar drugs of abuse including amphetamine (PA), methamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA) and ketamine (Ke) as the model analytes. The experimental results revealed that the titania-OH-TSO coated stir bar exhibited highly pH-resistant ability, good preparation reproducibility, superior selectivity and high extraction efficiency for the target compounds. Based on this fact, a new method of titania-OH-TSO coated stir bar sorptive extraction (SBSE) combined with high performance liquid chromatography (HPLC)–ultraviolet visible (UV) detection was developed for the analysis of five drugs of abuse in urine samples. The factors affecting the extraction efficiency of SBSE such as sample pH, desorption solvent, sample volume, extraction time, desorption time, stirring rate and ionic strength were investigated and the optimal extraction conditions were established. Under the optimized conditions, the limits of detection (LODs) for titania-OH-TSO coated SBSE–HPLC–UV determination of five polar drugs of abuse were in the range of 2.3–9.1 μg/L with relative standard deviations (RSDs) ranging from 7.3 to 8.9% ( c = 300 μg/L, n = 6), and all of the target compounds exhibited good linearity over a concentration range of 30–3000 μg/L. The developed method was applied to the determination of amphetamines and Ke in urine samples of drug abusers with satisfactory results.

Stability of drugs of abuse in urine samples stored at -20 degrees C.

Isolated studies of the stability of individual drugs of abuse have been reported. However, few have evaluated stability in frozen urine samples stored for 12 months. We have determined the stability of 11-nor-9-carboxy-delta 9-tetrahydrocannabinol (9-COOH-THC), amphetamine, methamphetamine, morphine, codeine, cocaine, benzoylecgonine, and phencyclidine in 236 physiological urine samples. Following the initial quantitative analysis, the samples were stored at -20 degrees C for 12 months and then reanalyzed. All drug concentrations were determined by gas chromatographic-mass spectrometric methods with cutoff concentrations of 5 ng/mL for 9-COOH-THC and phencyclidine and 100 ng/mL for each of the other drugs. The average change in the concentrations of these drugs following this long-term storage was not extensive except for an average change of -37% in cocaine concentrations.

A capillary column gas-chromatographic method for the identification of drugs of abuse in urine samples.

This paper describes the application of capillary column gas liquid chromatography (GLC) to the analysis of urine samples for drugs of abuse. A simple basic extraction into butylacetate is followed by temperature programmed analysis from 90 degrees C to 310 degrees C to provide a comprehensive screen for basic drugs. Retention data are presented for approximately 300 compounds. The use of capillary column GLC is compared with packed column methods used previously in this laboratory. The reproducibility of retention data and sensitivity of this analysis for several commonly encountered drugs are presented.