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Cloud point extraction (CPE) is a simple, safe and environment-friendly technique used in the preparation of various samples. It was primarily developed for the assessment of environmental samples, especially analyzed for metals. Recently, this technique has been used in the extraction and determination of various chemical compounds (e.g., drugs, pesticides and vitamins), in various matrices (e.g., human plasma, human serum, milk and urine). In this review, we show that CPE is a reliable method of extraction and can be used in analytical laboratories in combination with other techniques that can be used in the determination of drugs and other chemicals in the human biological matrix. According to the literature, a combination of different methods provides good recovery and can be used in the simultaneous determination of many drugs in a single analysis. CPE can be optimized by changing its conditions (e.g., type of surfactant used, incubation temperature, pH and the addition of salts). In this review, we present the optimized CPE methods used in the determination of various pharmaceuticals and describe how the conditions affect the performance of extraction. This data might support future designing of the new CPE applications that are simple and more accurate. We compared CPE with other extraction methods and also showed the advantages and disadvantages of various extraction techniques along with a discussion on their environmental impact. According to the publications reviewed, it is obvious that CPE is an easy, safe, rapid and inexpensive method of extraction., (© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The transition from presumptive (immunoassay) drug screening to definitive screening has continued in the practice of analytical toxicology. Development of a ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) screening method for over sixty drugs and metabolites (analytes) in urine has been reported by the authors and has been applied in probation, drug court, social services, chemical dependency, pain management and addiction medicine casework. Testing by the definitive screening method has increased both the rate and diversity of initial-positive drug findings, due to the lower positive thresholds and wider panel of analytes. Use of definitive screening in forensic casework, however, requires retesting of initial-positive analytes using a second method based upon a different analytical technique with at least equivalent sensitivity and selectivity. Consequently, a UPLC-MSE/TOF method for confirmation of the initial-positive analytes has been adapted; the method is for targeted confirmation and is based upon an alternate mass spectrometry technology and column separation. Both the initial screen and the confirmatory analysis employ threshold accurate calibration for normalization of matrix effects, without the use of stable isotopes. Validation and application of the complete workflow, in forensic urine drug testing casework, is reported., (© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

To intoxicated patients in the emergency room, toxicological analysis can be considerably helpful for identifying the involved toxicants. In order to develop a urine multi-drug screening (UmDS) method, gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS-MS) were used to determine targeted and unknown toxicants in urine. A GC-MS method in scan mode was validated for selectivity, limit of detection (LOD) and recovery. An LC-MS-MS multiple reaction monitoring (MRM) method was validated for lower LOD, recovery and matrix effect. The results of the screening analysis were compared with patient medical records to check the reliability of the screen. Urine samples collected from an emergency room were extracted through a combination of salting-out assisted liquid-liquid extraction (SALLE) and hybrid protein precipitation/solid phase extraction (hybrid PPT/SPE) plates and examined by GC-MS and LC-MS-MS. GC-MS analysis was performed as unknown drug screen and LC-MS-MS analysis was conducted as targeted drug screen. After analysis by GC-MS, a library search was conducted using an in-house library established with the automated mass spectral deconvolution and identification system (AMDISTM). LC-MS-MS used Cliquid®2.0 software for data processing and acquisition in MRM mode. An UmDS method by GC-MS and LC-MS-MS was developed by using a SALLE-hybrid PPT/SPE and in-house library. The results of UmDS by GC-MS and LC-MS-MS showed that toxicants could be identified from 185 emergency room patient samples containing unknown toxicants. Zolpidem, acetaminophen and citalopram were the most frequently encountered drugs in emergency room patients. The UmDS analysis developed in this study can be used effectively to detect toxic substances in a short time. Hence, it could be utilized in clinical and forensic toxicology practices.

Urine drug testing is common for workplace drug testing, prescription management, emergency medicine and the criminal justice system. Unsurprisingly, with the significant consequences based upon the results of urine drug testing, a donor in need of concealing the contents of their sample is highly motivated to cheat the process. Procedures and safeguards ensuring sample validity are well known, and include measuring sample temperature at the time of collection, and laboratory measurements of creatinine, specific gravity and pH. Synthetic urine samples are available and are designed to deceive all aspects of urine drug testing, including validity testing. These samples are sophisticated enough to contain biological levels of creatinine, and are at a physiological pH and specific gravity. The goal of our research was to develop new procedures designed to distinguish authentic samples from masquerading synthetic samples. We aimed to identify substances in commercial synthetic urines not expected to be present in a biological sample distinguishing fake specimens. Additionally, we aimed to identify and employ endogenous compounds in addition to creatinine for identifying biological samples. We successfully identified two compounds present in synthetic urines that are not present in biological samples and use them as markers of invalidity. Four new endogenous markers for validity were successfully evaluated. Validity assessment was further aided by monitoring metabolites of nicotine and caffeine. When the method was applied to patient samples, 2% of samples were identified as inconsistent with natural urine samples, even though they met the current acceptance criteria for creatinine, pH and specific gravity., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

For drug screening and pharmaco-/toxicokinetic analysis, bile as a major drug excretion route in addition to urine may be used in forensic autopsy cases; however, there are limited published data on correlations between bile and blood or urine drug concentrations. The present study retrospectively investigated drug concentrations in bile, compared with blood and urine concentrations, reviewing forensic autopsy cases during 6 years (January 2009-December 2014). Drugs were analyzed using automated gas chromatography-mass spectrometry following solid-liquid phase extraction. Compared with peripheral blood concentrations, bile concentrations were higher for most drugs; however, caffeine concentrations were similar. Bile concentrations were mostly lower than urine concentrations for amphetamines, caffeine and methylephedrine, but were usually similar to or higher for other drugs. Significant correlations were detected between bile and peripheral blood concentrations for amphetamines, several cold remedies, phenobarbital, phenothiazine derivatives and diazepam, as well as between bile and urine concentrations for amphetamines, caffeine, diphenhydramine, phenobarbital and promethazine derivatives. These findings suggest that bile can provide supplemental data useful in routine forensic toxicology, for the spectrum of drugs mentioned above, as well as for investigating pharmaco-/toxicokinetics and postmortem redistribution when analyzed in combination with drug concentrations at other sites., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: Liquid chromatography high-resolution mass spectrometry (LC-HRMS) with untargeted data collection is especially attractive for general unknown drug screening owing to its ability to identify unexpected compounds. LC-HRMS offers several advantages over traditional selected reaction monitoring (SRM) techniques and could be an ideal screening platform as long as its analytical performance is comparable to that of SRM-based methods., Methods: We developed a broad-spectrum drug screen on a high-resolution mass spectrometer [tandem quadrupole time-of-flight (QqTOF)] that collected data in an untargeted manner and compared its performance to a nominal mass instrument [triple quadrupole linear ion trap (QqLIT)] that collected data in a targeted manner. Both methods used information-dependent acquisition of product ion spectra. We evaluated the lower limits of detection and matrix effects for each method and compared their ability to identify drugs in 100 routine clinical urine samples. Additional information (patient prescription history, drug screening results, etc.) was used to confirm discordant results., Results: QqLIT was slightly more analytically sensitive than QqTOF; however, this difference did not significantly affect compound identification in patient samples. QqLIT identified 596 drugs in the urine samples, of which 531 (89%) were confirmed. QqTOF identified 515 drugs, of which 500 (97%) were confirmed. There were 562 instances of a confirmed drug (68 unique drugs) in the 100 urine samples; the methods were concordant in 469 of these instances., Conclusions: Overall, QqTOF performed similarly to QqLIT and could serve as an alternative method for general unknown screening., (© 2015 American Association for Clinical Chemistry.)

A rapid and sensitive ultra-HPLC/MSIMS (UHPLC/MSIMS) assay method for the simultaneous determination in human urine of 22 drugs belonging to different pharmaceutical groups was developed. The drugs were extracted from urine samples and then separated on a Zorbax Rapid Resolution High Definition SB-C18 column. The mobile phase consisted of methanol and water containing formic acid with gradient elution. The chromatographic separation time was 7 min. The MSIMS detector, equipped with an electrospray ionization source, was set up in both positive and negative modes. The lower LOQs for the drugs in this method were between 0.05 and 0.60 ng/mL. Calibration curves in human urine were generated in the range of 0.05-600 ng/mL. Method validation parameters such as intraday and interday precision, accuracy, extraction recovery, stability, selectivity, dilution integrity, and carryover effect for all the compounds were within the acceptable ranges. This simple and fast method was applied successfully to study the pharmacokinetics of four selected drugs in human urine collected from patients. This UHPLC/MS/MS method offers an attractive way forward for the development of a routine rapid analysis for selected substances, particularly given the growing amount of new information about drug properties.

Electromembrane extraction (EME) is a novel sample preparation technique in pharmaceutical, chemical, clinical and environmental analysis. This technique uses electromigration across artificial liquid membranes for selective extraction of analytes and sample enrichment from complex matrices. This review focuses on the setup, general procedure and parameters affecting the extraction efficiency of EME. An overview of innovations in EME (on-chip EME, low voltage EME, drop-to-drop EME, pulsed EME and EME followed by low-density solvent based ultrasound-assisted emulsification microextraction) is also presented in this article and attention is focused on the use of EME for pharmaceutical, chemical, clinical and environmental analysis.

An extensive search of published research and review articles indicates that enhancing the sensitivity and resolution of capillary electrophoresis (CE) is a very active area of interest. This review focuses on developments and applications in this field over several years, especially from 2009-present. It first reviews developments in the fields of online sample preconcentration and highly sensitive detection for sensitivity enhancement. The online sample preconcentration techniques cover all methods, from electrophoretic preconcentration, extraction-based preconcentration, micelle-based preconcentration and hybrid preconcentration to nanoparticle-based preconcentration. Attention is also given to multiple dimension separations, additives in buffer solution and capillary inner surface modifications that have been used to enhance the resolution and separation efficiency of complex samples in CE. The additives include nanoparticles, chiral selectors and other buffer additives that have been added to the buffer solution.

In medical practices, the determination of enantiomeric ratio of the chiral drugs is very important for their activities, bioavailabilities and biodegradation. Only homochiral medication is safe for humans. The chiral analysis in biological samples is the first and most important step. The present article describes the technical strategies of the enantiomeric resolution of racemic drugs in biological samples. Attempts have been made to describe sample preparation by solid-phase extraction and enantiomeric resolution by chiral high-performance liquid chromatography. Various chiral stationary phases used in chiral separations of racemic drugs have been described. Efforts are also made to discuss the chiral recognition mechanism and future perspectives of chiral analyses in biological samples.

Benzodiazepines have become commonly prescribed medicines worldwide in the therapy of anxiety, sleep disorders and convulsive attacks because they are relatively safe, with mild side effects. The availability of rapid, sensitive and selective analytical methods is essential for the determination of these drugs in clinical and forensic cases. Benzodiazepines are usually present at trace levels (μg/mL or ng/mL) in a complex biological matrix, and the potentially interfering compounds need to be removed before analysis. Therefore, a sample preparation technique is often mandatory, both to extract the drugs of interest from the matrices and to increase their concentration. An extended and comprehensive review is presented herein, focusing on bio-sample preparation (pretreatment, extraction and derivatization) and gas chromatographic methods applied for the quantification of 1,4-benzodiazepines.

Liquid chromatography-time-of-flight mass spectrometry (LC-TOFMS) is an emerging technique in toxicological drug screening. The applicability of vitreous humor as an alternative matrix for drug screening by LC-TOFMS in postmortem investigations was studied by comparison of findings in urine and vitreous humor in 50 autopsy cases. In addition, a cutoff value was determined for 70 drugs of toxicological relevance. The comparison study showed that vitreous humor is well-suited for qualitative screening analysis, although representativeness was not as good as urine because of less frequent metabolite detection. A total of 45 parent compounds and 24 metabolites were identified in vitreous samples; for urine, the figures were 55 and 39, respectively. The mean and median cutoff values were 0.072 and 0.023 mg/L, respectively, which are sufficient for routine casework according to the quantitative data available in the literature.

Background: The challenge in systematic toxicological analysis using gas chromatography and/or liquid chromatography coupled to mass spectrometry is to identify compounds of interest from background noise. The large amount of spectral information collected in one full-scan MS run demands the use of automated evaluation of recorded data files. We evaluated the applicability of the freeware deconvolution software AMDIS (Automated Mass Spectral Deconvolution and Identification System) for GC-MS-based systematic toxicological analysis in urine for increasing the speed of evaluation and automating the daily routine workload., Methods: We prepared a set of 111 urine samples for GC-MS analysis by acidic hydrolysis, liquid-liquid extraction, and acetylation. After analysis, the resulting data files were evaluated manually by an experienced toxicologist and automatically using AMDIS with deconvolution and identification settings previously optimized for this type of analysis. The results by manual and AMDIS evaluation were then compared., Results: The deconvolution settings for the AMDIS evaluation were successfully optimized to obtain the highest possible number of components. Identification settings were evaluated and chosen for a compromise between most identified targets and general number of hits. With the use of these optimized settings, AMDIS-based data analysis was comparable or even superior to manual evaluation and reduced by half the overall analysis time., Conclusions: AMDIS proved to be a reliable and powerful tool for daily routine and emergency toxicology. Nevertheless, AMDIS can identify only targets present in the user-defined target library and may therefore not indicate unknown compounds that might be relevant in clinical and forensic toxicology.

Chronic pain patients are frequently maintained on one or more powerful opioid medications in combination with other psychoactive medications. Urine tests provide objective information regarding patient compliance status. Little information is available on testing this unique population. The goal of this study was to characterize drug disposition patterns in urine specimens collected from a large population of pain patients. Confirmation data for 10,922 positive specimens were collated into 11 drug Classes. The number of drug/metabolites tested (#) and number of confirmed positive specimens were as follows: amphetamines (7), 160; barbiturates (5), 308; benzodiazepines (6), 2397; cannabinoids (1), 967; carisoprodol (2), 611; cocaine (1), 310; fentanyl (1), 458; meperidine (2), 58; methadone (2), 1209; opiates (7), 8996; and propoxyphene (2), 385. Subdivision into 19 distinct drug Groups allowed characterization of drug use patterns. Of the 10,922 positive specimens, 15,859 results were reported as positive in various drug Classes, and 27,197 drug/metabolites were measured by gas chromatography-mass spectrometry. The frequency of illicit drug use (cannabis, cocaine, ecstasy) was 10.8%. Being the first study of this type, these data present a large array of information on licit and illicit drug use, drug detection frequencies, drug/metabolite patterns, and multi-drug use combinations in pain patients.

Confirmation of opioids in urine samples of clinical patients requires liberation of opioids from their glucuronide conjugates. Both acid hydrolysis and enzyme hydrolysis using beta-glucuronidase from various sources have been reported, with the latter approach prevailing in most clinical toxicology laboratories. The goal of this study was to compare the efficiency of acid versus different enzyme hydrolysis methods in recovering morphine and common semisynthetic opioids from glucuronide standards and 78 patient urine samples that were screened positive for opioids as a class. Specimens were analyzed with a validated gas chromatography-mass spectrometry (GC-MS) procedure. With the exception of oxycodone, the results indicated that the majority of opioids tested were extensively glucuronide-conjugated in urine. Significantly, acid hydrolysis liberated > 90% of morphine and hydromorphone from their glucuronide standards but enzyme hydrolysis had lower and variable efficiency, depending on the opiate type and the enzyme source. In patient specimens, much higher concentrations of free codeine, morphine, hydromorphone, and oxymorphone were obtained with acid hydrolysis than with various enzyme methods. Incomplete hydrolysis using beta-glucuronidase could lead to false-negative results for many opioids when urine is tested for drugs of abuse. We conclude that acid hydrolysis is the method of choice for GC-MS confirmation of urine opioids.

Background: In clinical and forensic toxicology, general unknown screening is used to detect and identify exogenous compounds. In this study, we aimed to develop a comprehensive general unknown screening method based on liquid chromatography coupled with a hybrid triple-quadrupole linear ion trap mass spectrometer., Methods: After solid-phase extraction, separation was performed using gradient reversed-phase chromatography. The mass spectrometer was operated in the information-dependent acquisition mode, switching between a survey scan acquired in the Enhanced Mass Spectrometry mode with dynamic subtraction of background noise and a dependent scan obtained in the enhanced product ion scan mode. The complete cycle time was 1.36 s. A library of 1000 enhanced product ion-tandem mass spectrometry spectra in positive mode and 250 in negative mode, generated using 3 alternated collision tensions during each scan, was created by injecting pure solutions of drugs and toxic compounds., Results: Comparison with HPLC-diode array detection and gas chromatography-mass spectrometry for the analysis of 36 clinical samples showed that linear ion trap tandem mass spectrometry could identify most of the compounds (94% of the total). Some compounds were detected only by 1 of the other 2 techniques. Specific clinical cases highlighted the advantages and limitations of the method., Conclusion: A unique combination of new operating modes provided by hybrid triple-quadrupole linear ion trap mass spectrometers and new software features allowed development of a comprehensive and efficient method for the general unknown screening of drugs and toxic compounds in blood or urine.

This paper reviews liquid chromatographic-mass spectrometric (LC-MS) procedures for the screening, identification and quantification of doping agents in urine and other biological samples and devoted to drug testing in sports. Reviewed methods published approximately within the last five years and cited in the PubMed database have been divided into groups using the same classification of the 2004 World Anti-Doping Agency (WADA) Prohibited List. Together with procedures specifically developed for anti-doping analysis, LC-MS applications used in other fields (e.g., therapeutic drug monitoring, clinical and forensic toxicology, and detection of drugs illicitly used in livestock production) have been included when considered as potentially extensible to doping control. Information on the reasons for potential abuse by athletes, on the requirements established by WADA for analysis, and on the WADA rules for the interpretation of analytical findings are provided for the different classes of drugs.

Poor availability of reference standards for designer drugs, metabolites, and new substances prevents toxicology laboratories from rapidly responding to the changing analytical challenges of drug abuse. A novel screening approach comprising determination of accurate masses of sample components and comparison of these with databases of theoretical monoisotopic masses is described. Using liquid chromatography-time-of-flight mass spectrometry (LC-TOFMS), a routine mass search window of 20-30 ppm was applied to urine samples. The ultimate reference technique, liquid chromatography-Fourier transform mass spectrometry (LC-FTMS), was capable of confirming the findings within a 3 ppm mass accuracy. Using a target database of 7640 compounds, the number of potential elemental formulas ranged from one to three with LC-TOFMS, and it was always one with LC-FTMS. In contrast to ordinary techniques requiring primary reference standards, the formula-based databases can be updated instantly with fresh numeric data from scientific literature and authority sources.

The objective of this study was to develop a screening process for the analysis of sexual assault samples. Recently, the Society of Forensic Toxicologists created a committee to address the issue of drug-facilitated sexual assault (DFSA) in the toxicology field. This committee prepared a list of drugs that could be, or have been, used in DFSAs. The list comprises about 50 compounds, including illicit, prescription, and over-the-counter drugs. Using this list, our laboratory wanted an easy, fast, and sensitive method to analyze a urine sample for all 50 of these drugs. We screened and confirmed for 20 compounds, including cocaine, amphetamines, benzodiazepines, barbiturates, opiates, methadone, alcohol, and PCP. A gas chromatographic-mass spectrometric screening method that was able to detect the remaining 30 compounds following 1 extraction and using only 2 mL of urine was developed. The process is inexpensive and uses equipment available in most forensic toxicology laboratories. This method is recommended for any laboratory that commonly receives specimens collected from sexual assault victims and is interested in a more thorough analysis.

A rapid, sensitive, and rugged method for detecting drugs and drug metabolites in extracts of horse urine is described. The use of large-volume injection (LVI) gas chromatography-mass spectrometry (GC-MS) for analysis of horse urine extracts allowed automation of the derivatization procedure and reduction of the sample volume from 5 mL to 1 mL of urine. An autosampler and temperature-programmable inlet were used to automatically dissolve the sample extract and form trimethylsilyl derivatives of over 200 analytes. The suitability of this procedure for routine GC-MS detection of approximately 80 basic analytes in extracts of racehorse urine was investigated. The formation of derivatives using LVI with in-liner derivatization was compared to a manual procedure involving the dissolution of sample extracts in N,O-bis(trimethylsily)trifluoroacetamide, heating the resulting mixture, and injecting 1 or 2 microL of the mixture through a splitless injector into the GC-MS instrument. In all cases, the in-liner derivatization reactions were found to be as complete as conventional heating block procedures. Ruggedness testing of the method demonstrated that peak resolution, shape, and area were maintained through 40 consecutive injections of sample extracts. No evidence of the accumulation of interfering substances was observed. The limits of detection using LVI GC-MS for routine screening of basic drugs in urine were generally in the range of 5-25 ng/mL. The method is currently being used to detect basic analytes in horse urine extracts with a throughput of approximately 50 urine sample extracts per instrument per day.

A dual-plate overpressured layer chromatography (OPLC) method was evaluated for broad-scale screening of basic drugs in 2-mL autopsy urine samples. Extraction was carried out by mixed-mode solid-phase extraction, and identification was based on automated comparison of corrected Rf values (hRfc) and in situ UV spectra with library values by dedicated software. The day-to-day precision of hRfc values was good in both OPLC1 and OPLC2 systems with median relative standard deviations of 2.4% and 3.4%, respectively. Both Rf and hRfc values were independent of the amount of analyte (0.5-10 microg) applied to the plate. Detection limits were determined for 47 drug substances in 2-mL urine samples, and they varied between 0.05 and 3.5 mg/L with a median of 1.0 mg/L. The performance of OPLC was evaluated by analyzing 30 autopsy urine samples by both OPLC and gas chromatography-mass spectrometry (GC-MS). The majority of findings by OPLC were in agreement with GC-MS. Some substances with low concentrations were not detected by OPLC, whereas GC-MS failed to detect a few polar substances. The OPLC method thus provides an alternative for current planar and column liquid chromatographic drug screening methods with the possibility of lowering detection limits by using a larger sample size.

Background: In chronic renal failure, the renal excretion of certain drugs is dramatically reduced. To determine whether other routes of drug elimination, such as secretion through the intestinal barrier by intestinal P-glycoprotein can be altered, we compared P-glycoprotein activity, P-glycoprotein protein content, and P-glycoprotein mRNA levels in intestine of control and chronic renal failure rats., Methods: Chronic renal failure was surgically induced in rats by partial (7/8) nephrectomy. After 5 weeks, intestinal transport of rhodamine 123, a P-glycoprotein substrate, was carried out using an in vitro model of everted gut sacs. P-glycoprotein protein content was quantified by enzyme-linked immunosorbent assay and P-glycoprotein mRNA expression was evaluated by semi-quantitative reverse transcriptase polymerase chain reaction., Results: A decrease of intestinal rhodamine 123 transport was observed in chronic renal failure rats, pointing to an inhibition of P-glycoprotein activity. Transport was inhibited in both sham-operated rats and rats with chronic renal failure by verapamil and cyclosporin A, but relative inhibition vs baseline was less marked in chronic renal failure than in sham-operated rats. In contrast, no significant differences in levels of P-glycoprotein protein or mRNA were observed between the two groups., Conclusions: Intestinal secretion of rhodamine 123 is mainly mediated by P-glycoprotein. It was reduced in rats with chronic renal failure, reflecting reduced intestinal drug elimination via a decrease in P-glycoprotein transport activity rather than via protein underexpression.

A method for analyzing urine for the presence of basic drugs and their metabolites using two fused silica capillary columns is described along with operating conditions and column characteristics. Urine extracts were injected into a gas chromatograph equipped with nitrogen phosphorous detectors (GC/NPD) and two capillary columns, housed in a single injection port. The injected material was simultaneously chromatographed in each column. Identification of unknowns was done using relative retention times.

I have adapted, for use with a centrifugal analyzer, reagents from 10 different EMIT (Syva Co.) enzyme immunoassay urine drug-detection kits, reagents from another five serum kits, and reagents for determining ethanol. Assays for individual drugs in 100 microL of urine and in 100 microL of serum are performed simultaneously rather than sequentially in less than 15 min, with one-tenth the usual amount of reactants (sample + reagents). These assays, when combined with other easily performed tests, provide a rapid toxicology screen well-suited for evaluating acute emergency patients, and for performing a small number of daily routine screens. The total screen requires 500 microL of urine and 500 microL of serum. I summarize my experience with this procedure in its first year of use, and discuss differences between testing for the care of patients compared with searching for evidence of illegal drug use.

The authors prospectively performed simultaneous determinations of serum delta osmolality (delta-Osm), enzymic (alcohol dehydrogenase [ADH]) quantitation of serum ethanol (EtOH), and urine drug screens on 339 acutely intoxicated patients. In addition, the authors established reference ranges for measured and calculated serum osmolalities in a group of 55 healthy volunteers. The authors determined the clinical utility of the combined delta-Osm/ADH procedure for detecting the presence of EtOH or other low molecular weight (Mr) volatiles. In the reference population, the measured osmolality (M-Osm) and calculated osmolality (C-Osm) was 285.1 +/- 4.3 (SD) mOsm/kg and 287.4 +/- 5.1 (SD) mOsm/kg, respectively. The correlation between delta-OsM and serum EtOH was 0.968 in 151 patients in whom EtOH was detected. The presence of drugs in 67 (44%) patients or absence of drugs in 84 (55.6%) patients was shown to have no significant effect on the delta-Osm. The delta-Osm/ADH method failed to detect a volatile other than EtOH in only two cases (0.6%) or in addition to EtOH in three cases (0.9%). The concentrations of these volatiles were not clinically significant. The sensitivity for detecting EtOH by means of the delta-Osm calculation was 98.1% with a specificity of 98.2%. A disparity (delta-Osm greater than 10 mOsm/kg) between delta-Osm and the EtOH determination suggested a volatile other than EtOH in five cases (1.5%), which was confirmed by head-space gas chromatographic (GC-HS) analysis. A volatile in addition to EtOH in seven cases (2.1%) was suggested but not confirmed by GC-HS analysis. The delta-Osm/ADH procedure provides an efficient, rapid, and readily available method to evaluate the acutely intoxicated patient for the presence of EtOH and/or other low Mr volatiles.

Recently, the use of a prolonged and combined procedure of hemoperfusion (HP) and hemodialysis (HD) was considered as a treatment for severely intoxicated patients caused by drug overdose. Working in cooperation with different hospitals, this laboratory has been involved with the toxicological analysis of biological samples taken during such a treatment. This paper describes the use of a combined HP/HD treatment, especially the evaluation of the system, by giving the analytical results obtained by gas chromatography. The methods utilized enable this application for routine toxicological analysis.

A simple direct colorimetric test using a tetrabromophenolphthalein reagent for detecting basic drugs in urine is described. The response of 62 commonly encountered drugs and metabolites to this test are described and 39 of these compounds were found to react. The sensitivity for many of the drugs is adequate for their detection following recommended therapeutic doses.

A capillary column gas chromatographic (GC) method is described for detecting basic drugs of abuse and their metabolites in urine. One milliliter of urine, buffered with 400 microL Tris buffer (pH 9.5) containing 1.0 microgram/mL internal standard SKF 525A (proadifen hydrochloride), is extracted with 100 microL of 5% (v/v) isoamyl alcohol/hexane. The sample is vortexed for 30 sec and centrifuged for 10 min. The upper organic layer is directly injected into the GC, thus eliminating the need for an evaporation step. The GC is equipped with two DB-1701 fused silica capillary columns and nitrogen phosphorus detectors. The column oven is temperature programmed from 185 degrees to 265 degrees C at 8 degrees/min. Identification of the unknown drugs is accomplished by using retention time relative to that of a common internal standard.

The computer-assisted liquid chromatographic system (MCASYST) is developed for automated identification and analysis. The system has six main functions: retention prediction system, liquid chromatographic data base system, automated identification system, optimization of separation conditions, data loading program from UV multichannel detector, and UV spectral data base system. The performance and potential of this MCASYST system is evaluated for toxic compounds identification in poisoned human fluids.

The equipment, methods, logistics, and results of doping-control analyses for the 1984 Los Angeles Olympic Games are discussed in this article. Within 15 days, 1510 different urine specimens underwent 9440 screening analyses by a combination of gas chromatography, gas chromatography-mass spectrometry, "high-performance" liquid chromatography, and radioimmunoassay. These tests covered more than 200 different drugs and metabolites, including psychomotor stimulants, sympathomimetic amines, central nervous system stimulants, narcotic analgesics, and anabolic steroids. The results are summarized by class of drug. Less than 2% of the samples were found to contain a banned drug.

From a modest beginning, QSIM has established itself with over three hundred applications in the 1970s as not only a reference technique for other methods but also as a useful method in its own right for the quantitation of drugs in biological matrices. Relative to its potential sensitivity, the actual sensitivity of QSIM drug assays is disappointing, although a number of QSIM drug assays report LOQs of 250 pg ml-1 or less. The mean reported precision of QSIM drug assays (approximately 6%) is similar to that of traditional GC and LC assays, but is an order of magnitude less than either what is theoretically possible or what has been demonstrated in a few selected QSIM assays.

This paper presents the methodological aspects of a computerized system for the gas-chromatographic screening and primary identification of central nervous system stimulants and narcotic analgesics (including some of their respective metabolites) extracted from urine. The operating conditions of a selective nitrogen detector for optimized analytical functions are discussed, particularly the effect of carrier and fuel gas on the detector's sensitivity to nitrogen-containing molecules and discriminating performance toward biological matrix interferences. Application of simple extraction techniques, combined with rapid derivatization procedures, computer data acquisition, and reduction of chromatographic data are presented. Results show that this system approach allows for the screening of several drugs and their metabolites in a short amount of time. The reliability and stability of the system have been tested by analyzing several thousand samples for doping control at major international sporting events and for monitoring drug intake in addicts participating in a rehabilitation program. Results indicate that these techniques can be used and adapted to many different analytical toxicology situations.

In a prospective drug-testing program, individuals whose job classifications have been defined as sensitive are placed in a selection pool. Periodically, individuals are chosen from this pool for drug testing. Random selection is a fair and impartial approach for this because each individual has an equal chance of being selected. Random selection also serves to reinforce the deterrent potential of a drug-testing program because individuals in the pool never know when or if they will be selected. This uncertainty discourages drug usage because of the risk involved in being selected and tested. A random selection process generates a Poisson distribution of probabilities that can be used to predict how many times an individual will be selected during a specific time interval. This information can be used to model the selection part of a drug-testing program to determine whether specific conditions of testing are met. For example, the probability of being selected a given number of times during the testing period can be minimized or maximized by varying the frequency of the sampling process. Consequently, the Poisson distribution and the mathematics governing it can be used to structure a drug-testing program to meet the needs of any given situation.

This paper describes a novel technique for the rapid screening of drugs of abuse in urine involving extraction with encapsulated Amberlite XAD-2 resin followed by gas chromatographic analysis. Each capsule is fabricated as a rigid, porous, polypropylene sphere, 2 cm in diameter, and contains 300 mg of the XAD-2 resin. Two mL of urine is shaken with one capsule under slight positive pressure for eight minutes. A sequential extraction is employed to obtain separate elution of the acidic-neutral and basic drugs. Identification is by dual column gas chromatography. The results, as given for spiked urine samples containing 16 commonly encountered drugs, were found to be linear and reproducible over both the therapeutic and toxic ranges. Extraction efficiencies using the encapsulated XAD-2 technique are comparable to those reported in literature for XAD-2 column chromatography. The purity of the extracts, as seen from the gas chromatographic analysis, is demonstrably better than that seen with the conventional procedures. There was minimal interference from polymer bleed. The total volume of solvents used in the sequential scheme is 5 mL. Total extraction time to achieve dried residues is 15 minutes.

A rapid extraction method preliminary to analysis for drugs in urine is described. Extraction columns containing purified cotton fiber (JETUBE, Manhattan Instrument Co., Santa Monica, Calif.) are shown to give high (approximately 90-97%) extraction efficiencies for some commonly prescribed or abused drugs, notably phenobarbital, amphetamine, morphine, and methadone. Analysis time, extraction efficiency, convenience, and eluate purity with a modified JET procedure are shown to be superior to results obtained with XAD-2 resin columns.

A rapid screening technique is presented for the detection of underivatized drugs using a multi-level temperature program. This allowed for the identification of major clinically significant drugs extracted from serum, urine, and other body fluids. Acidic or basic extractions are injected into a gas chromatograph equipped with a flame ionization detector and a single wide-bore, thick film capillary using the splitless mode of injection. Identification is by retention time relative to that of a common internal standard. Deactivation of the fused silica liner is necessary to consistently detect low concentrations of specific drugs.

The utility of performing comprehensive toxicology screening in patients admitted to a university trauma center was evaluated by retrospective review of the results of such screening for a one-year period. Eighty-five percent of the screens were performed on males. Sixty-nine percent of the screens were positive for one or more drugs, and eighty-five percent of the positive screens occurred in males. More than half of the positives were in individuals 30 years of age or less. Ethanol was present in 81% of the positive screens, and of these it was the only drug found in 84% of the cases. Blood ethanol concentrations for the entire series ranged from 0.01 to 0.41% (mean, 0.15%; SD, 0.08%). Blood ethanol measurement alone is more cost effective than comprehensive toxicology screening and may be nearly as useful as the comprehensive screen in the majority of trauma cases.

Hundreds of drugs and other substances are excreted in urine. In a comprehensive drug screen, it is impossible to identify every detectable substance. In order to delineate the most commonly detected drugs, approximately 1000 urine specimens from geographically distributed clinical laboratories were analyzed for drug substances. Twenty-nine (29) clinical laboratories submitted up to 76 consecutive urine specimens found to be positive for substances other than nicotine and caffeine. Specimens were analyzed by thin layer chromatography and special procedures for salicylates, benzoylecgonine, PCP, benzodiazepines, and cannabinoid metabolites. Every specimen was also tested for opiates, PCP, and cannabinoid metabolites by an enzyme immunoassay procedure. The total number of drugs detected in 1000 specimens was 3014, an average of three drugs per specimen; and 110 different drugs were identified. Of these, 50 drugs accounted for 95% of the total detected; 21% of the specimens contained cannabinoid metabolites, and 4% of the specimens contained cocaine and/or benzoylecgonine. Most of the specimens were routine, and only 4% originated from comatose patients.

An evaluation of Technology Resources Inc. (TRI) Amphetamine, Barbiturate, Narcotic (G) and Narcotic (S) "Dipsticks" for drugs of abuse in urine was made. The results obtained by six individuals reading the "Dipstick" papers was compared with the analysis of the same urine samples, by a combination of TLC, EMIT, RIA and GLC. The data obtained with "Dipstick" papers, regardless of the drug tested, were clearly unreliable (high percentage of false negatives, low percentage of true positives) and the assay was unsuitable as a technique for screening urines for drugs of abuse.