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Many natural products have biological effects on humans and animals. Poisoning caused by natural products is common in clinical toxicology cases. Liquid chromatography–high-resolution mass spectrometry (LC–HRMS) has recently emerged as a powerful analytical tool for large-scale target screening, and the application of LC–HRMS can be expanded to evaluate potential natural product poisoning in clinical cases. We report the construction of an LC–HRMS spectral library of 95 natural products commonly implicated in poisoning, and an LC–HRMS assay was validated for definitive detection of natural products in urine and serum samples. For each compound, the limit of detection was determined in the analytical range of 1.0–1,000 ng/mL for urine samples and 0.50–500 ng/mL for serum samples. The mean (SD) values of matrix effects for urine samples and that for serum samples were both −21% (22%), and the mean (SD) value of recovery for serum samples was 89% (26%). The LC–HRMS assay was successfully applied to identify natural products in clinical cases. The spectral library parameters of each compound are provided in the supplementary material to aid other laboratories in identification of unknown natural toxins and development of similar methods on different mass spectrometry platforms.

Benzodiazepines (BZDs) are widely used for treatment of anxiety and insomnia, however, this class of drugs is also commonly abused. Many different BZDs and analogs have been produced that are not FDA-approved. We tested 15 of these with the ThermoFisher CEDIA® BZD-immunoassay. With the exception of ketazolam, all compounds showed significant reactivity, highlighting the need for mass spectrometry confirmation assays. We developed a liquid-chromatography high-resolution mass spectrometry method for the detection of these 15 non-FDA approved BZDs. The limit of detection for most compounds ranged from 1 to 50 ng/mL, with mostly positive matrix effects observed in urine and negative matrix effects in serum. In a clinical research case, clonazolam and etizolam were detected in serum at 10.2 and 281 ng/mL, with an apparent elimination half-life of 3.6 and 4.8 hours, respectively. Although we did not detect non-FDA approved BZDs in 211 urine samples that were previously determined to be BZD-positive by immunoassay, abuse of these drugs is on the rise and clinical and forensic toxicology laboratories should consider developing methods to detect them.

The postmortem redistribution phenomenon is an important factor in the interpretation of blood drug concentrations as a cause or factor in death. Intraosseous fluid (IOF) may serve as an alternative matrix for drug testing. Intraosseous fluid was collected from the left and right tibias and humerus of 29 decedents using the Arrow EZ-IO Intraosseous Vascular Access System. Standard autopsy specimens including blood were also collected at the same time during autopsy. Blood and IOF specimens were screened by immunoassay for opioids, fentanyl analogs, oxycodone, methadone, cocaine, methamphetamine, amphetamines, phencyclidine, tricyclic antidepressants, benzodiazepines and cannabinoids, using commercially available enzyme-linked immunosorbent assay (ELISA) kits. Correlation between cardiac/central blood ELISA and IOF ELISA results was mostly 100% for drug targets. Further blood confirmation analysis was performed by gas chromatography mass spectrometry also showed comparable correlation to IOF screen results. There was no significant difference between the IOF sites or sides of the body. This novel study supports the use of IOF as an alternative postmortem specimen for toxicological investigations as a potentially less-compromised tissue in decomposed or traumatized bodies. Preliminary data is provided for the screening of common drugs of abuse in IOF that may show to be subject to alternative rates of postmortem redistribution than to that of other biological specimens in future studies that quantitate IOF drug concentrations.

Fentanyl and its analogs, such as acetylfentanyl, have become a concern for potential abuse. Fentanyl compliance monitoring and urine drug testing are becoming increasingly necessary; however, a limited number of fentanyl immunoassays have been validated for clinical use. The purpose of this study was to validate the use of the DRI® fentanyl immunoassay, determine the potential cross-reactivity of acetylfentanyl and other pharmaceuticals, and investigate acetylfentanyl use in San Francisco. All urine toxicology samples from patients presenting to the emergency department were analyzed using the fentanyl immunoassay for 4 months. Positive samples were analyzed qualitatively using liquid chromatography-high resolution mass spectrometry (LC-HRMS) for fentanyl, fentanyl metabolites, fentanyl analogs and greater than 200 common drugs and metabolites. Subsequently, quantitative analysis was performed using LC-tandem mass spectrometry (LC-MS-MS). Acetylfentanyl, risperidone and 9-hydroxyrisperidone were found to cross-react with the fentanyl immunoassay. No acetylfentanyl was detected in our emergency department patient population. The fentanyl immunoassay demonstrated 100% diagnostic sensitivity in a subset of urines tested; however, the specificity was only 86% due to seven false-positive samples observed. Five of the seven samples were positive for risperidone and 9-hydroxyrisperidone. The DRI® fentanyl immunoassay can be used to screen for fentanyl or acetylfentanyl; however, confirmatory testing should be performed for all samples that screen positive.

With the rise in the use and misuse of prescription opioids, there is an increasing need for the confirmed identification of opioid analgesics in toxicology laboratories. The goals of this study were to (i) systematically evaluate the hydrolysis efficiency of four β-glucuronidase enzymes under optimized condition; (ii) evaluate compound recovery, matrix effects and precision of three protein precipitation plates and (iii) develop and validate a qualitative liquid-chromatography mass spectrometry (LC-MS/MS) assay to identify 13 opioids in urine. A recombinant β-glucuronidase exhibited the best overall hydrolysis efficiency for seven opioid glucuronide conjugates compared with β-glucuronidase from red abalone, Escherichia coli and Patella vulgata One of the protein precipitation plates tested exhibited overall better recovery of the opioids and lower ion suppression compared with the other two plates. An ESI positive mode LC-MS/MS assay for qualitative opioid analysis was developed and validated. Linearity, LOD, precision, matrix effect, recovery, carryover and interference of the method were evaluated. Sixty-two patient samples were analyzed by both a legacy GC-MS opioid method and the LC-MS/MS method, and 22 samples were analyzed by the LC-MS/MS and an LC-MS/MS reference method. The results of the comparisons showed good concordance. Overall, we described an efficient sample preparation procedure for a sensitive qualitative opioid confirmation assay in urine.

The opioids codeine and morphine have legitimate uses in managing chronic pain conditions, but they are frequently abused. Patients prescribed opioids submit urine samples for medication compliance monitoring, and the interpretation of the results is complex. The purpose of this study was to evaluate the percentage of codeine- and morphine-positive urine drug tests that result from morphine use only, with the positive codeine result arising from low levels of codeine present in pharmaceutical formulations of morphine. This study included 80 urine samples which tested positive for codeine and morphine after pre-analytical hydrolysis and analysis by gas chromatography-mass spectrometry. Quantitative results were correlated with patient prescription information and immunoassay results to classify patients into one of four categories: heroin users (50%), codeine users (34%), codeine and morphine users (5%), and morphine users (11%). The percentage of codeine-positive resulting from morphine use was higher than previous estimates. Urine from patients prescribed morphine only was found to contain codeine at

The consumption of poppy seeds in various foods may lead to a positive opiate result in urine subjected to testing for drugs of abuse. As a natural constituent of poppy seeds, thebaine was investigated as a possible marker for poppy seed consumption. Poppy seeds were examined for opiate content by gas chromatography-ion trap mass spectrometry (GC-MS) after extraction with methanol. Urine samples spiked with thebaine and urine from subjects given 11 g of poppy seeds were tested for the presence of thebaine, codeine, and morphine. Street heroin, one morphine and one codeine tablet, and urine from individuals who had used heroin were also examined for thebaine. Urine specimens were screened by enzyme immunoassay (EMIT) and confirmed for thebaine by GC-MS using a solid-phase extraction method. The GC-MS assay showed a linear response over a range of 1-100 ng/mL and a limit of detection of 0.5 ng/mL. Thebaine was detectable in the urine of poppy seed eaters in concentrations ranging from 2 to 81 ng/mL. Because thebaine was absent in powdered drugs and the urine of true opiate drug users, thebaine is proposed as a direct marker for poppy seed use.

A total of 2259 urine samples were assayed for lysergic acid diethylamide (LSD) using radioimmunoassay (RIA, Coat-a-Count, Diagnostics Products) and a premarket cloned enzyme donor immunoassay (CEDIA, Boehringer Mannheim). Urine samples were obtained from patients admitted to the emergency room, patients in drug rehabilitation programs, and adults and juveniles in criminal probation programs. An overall incidence of positive results was 0.80% for CEDIA (500-pg/mL cutoff) and 0.89% and 0.18% for RIA at cutoffs of 250 and 500 pg/mL, respectively. Of the CEDIA-positive samples, only 17 and 11% were positive by RIA at 250 and 500 pg/mL, respectively, whereas among RIA-positive samples, only 10% of those > 250 pg/mL and only 25% of those > 500 pg/mL were positive by CEDIA. Moreover, only 2 of 25 of samples positive by one of these screening assays were confirmed by gas chromatography-mass spectrometry (GC-MS). It is likely that discrepancies in results between immunoassays are due to differences in antibody specificities used to detect LSD metabolites. In addition, immunoassays may be more sensitive than GC-MS for detecting LSD use as current confirmation assays are targeted towards detection of the parent drug only. The interpretation of results for LSD analysis must be made with knowledge of the limitations for each assay.

Previous studies have shown that the ion response of a compound can be suppressed by the presence of a large amount of a coeluting substance in a gas chromatographic-mass spectrometric (GC-MS) system. In the present study, the change in the ion current of a constant amount of diazepam-d5 in the presence of a 100-fold amount of diazepam was used to monitor this condition in the Hewlett Packard mass selective detector (MSD). It was observed that a reduced recovery of ions occurred when the potentials of the MSD source elements were established by the autotune algorithm. Increasing the ion focus or the entrance lens potentials or both increased the recovery of the ion current of diazepam-d5 in the presence of large amounts of diazepam. The data suggested that the decreased recovery of ion current observed when the autotune source parameters were used was due to insufficient energy on the focusing lenses to extract a constant fraction of the ions from the source when a high concentration of molecules was present.

The Triage Panel for Drugs of Abuse (DOA) was evaluated for detection of phencyclidine (PCP), amphetamines (AMPH), opiates (OPI), tetrahydrocannabinol (THC), the cocaine metabolite benzoylecgonine (BE), and barbiturates (BARB) in urine. This assay was compared with Syva EMIT. The comparisons were conducted on 606 positive and 325 negative samples. When there was a sufficient volume of sample available for retesting, positive and negative samples with discordant results between these two screening assays were confirmed by quantitative gas chromatography/mass spectrometry (GC/MS). The percent agreement between the two assays for positive samples ranged from 93 to 100%. For negative samples, the agreement ranged from 95 to 100%. For AMPH, 19 out of 27 discordant samples of urine that were positive for EMIT and negative for Triage DOA contained total amphetamine and methamphetamine concentrations of less than 1000 ng/mL by GC/MS. For THC, seven urine samples that were negative for Triage DOA and positive for EMIT contained 9-carboxy THC concentrations at greater than 15 ng/mL by GC/MS. For BARB, three samples that were negative for Triage DOA and positive for EMIT contained barbiturates levels greater than 300 ng/mL. Two of these three samples contained phenobarbital below the concentration that produces a positive result for Triage DOA. For the majority of the urine samples studied, however, the Triage DOA produced identical results to a commercial-instrument-based immunoassay. Language: en

The serum and urine from 44 consecutive patients that tested positive for the cocaine metabolite benzoylecgonine (BE) were examined for free cocaine, ecgonine methyl ester (EME), and other metabolites by gas chromatography/ion trap mass spectrometry (GC/MS). In 13 of these patients, unique ethanol-related cocaine metabolites, cocaethylene and ecognine ethyl ester (EEE), were detected in urine and serum. One was from a newborn baby whose mother's blood was positive for cocaine and negative for cocaethylene. In two other patients, isopropanol was also consumed with cocaine and ethanol. In one of these two, cocaisopropylene and ecognine isopropyl ester (EPE) were identified in urine. The urine ethanol concentration in 7 of the 13 cocaethylene-positive patients ranged from 19 to 322 mg/dL. In the other six, ethanol was not detected in the urine. However, each of these latter patients had either prior serum results that were positive for ethanol or admitted to recent alcohol abuse. In the remaining 31 of 44 cocaine-positive patients, ethanol and the alcohol-specific cocaine metabolites were absent. The detection of alcohol-related cocaine metabolites is fairly common in a cocaine-positive patient population.

An underivatized methane chemical ionization (CI) assay for measuring amphetamines in urine was evaluated against derivatized electron impact (EI) assays using a gas chromatograph-ion trap mass spectrometer. The full-scan CI mass spectra of methamphetamine, ephedrine/pseudoephedrine, and phentermine were compared with the full scan and three-ion EI mass spectra of heptafluorobutyric anhydride (HFBA) and 4-carbethoxyhexafluorobutyryl chloride (CB) derivatives. The fragmentation patterns for these compounds were nearly identical for the three major high molecular weight ions (m/z 254, 210, and 169 for EI-HFBA derivatives, and m/z 308, 262, and 280 for EI-CB derivatives). The CI mass spectra of the underivatized drugs contained more discernible differences at the higher molecular weights, including m/z 119, 148, and 150 for methamphetamine, 148, 166, and 176 for ephedrine/pseudoephedrine, and 91, 133, and 150 for phentermine. The within-run precision ranged from 7-9% for CI versus 5-6% for EI with HFBA derivatization (mean 500 ng/mL, n = 5). The limits of detection (LOD) for amphetamine and methamphetamine were 2.4 and 8.6 ng/mL, respectively, for CI versus 0.7 and 1.4 ng/mL for EI. The limits of quantitation (LOQ) were 4.5 and 19.1 ng/mL for CI versus 1.4 and 5.7 ng/mL for EI. The use of full-scan mass spectral analysis with either electron impact or chemical ionization provides additional qualitative data that may be helpful for measuring methamphetamine in the presence of other sympathomimetic amines.

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.

A new sample preparation procedure is described for the extraction and simultaneous elution and derivation of urine for analysis of 11-nor-9-carboxy-delta 9-tetrahydrocannabinol (THC-COOH) by gas chromatography/ion trap mass spectrometry (GC/MS). Urine samples are extracted for THC-COOH and d6-THC-COOH internal standard onto a hydrophobic membrane. Extracts are simultaneously eluted and derivatized with MSTFA while on the membrane to produce the corresponding trimethylsilane derivative. Using results of blank urine, the limits of detection and quantitation were 1.1 and 2.5 ng/mL, respectively. The linearity of the assay was 250 ng/mL. The within-run and day-to-day precision ranged 3-5%. Compared with a solid-phase column extraction procedure, the overall time for sample preparation was decreased from 3 h down to 1. The SPEC extraction procedure with trimethyl derivatization produces a cleaner total ion chromatogram than the solid-phase column extraction system (minicolumn) and does not require the use of any organic solvents.

Analytical methods developed for the Finnigan MAT ITS40 gas chromatograph-ion trap mass spectrometer (GC/MS) were evaluated for the confirmation of drugs-of-abuse in urine. The specific drugs evaluated are those listed by the National Institute on Drug Abuse (NIDA): 11-nor-9-carboxy-delta 9-tetrahydrocannabinol (9-carboxy-THC), benzoylecgonine (BE), codeine and morphine, phencyclidine (PCP), amphetamine, and methamphetamine. Drugs were extracted from urine using solid-phase columns, separated by capillary gas chromatography, and analyzed by ion trap mass spectrometry following electron impact ionization. All drugs except PCP were derivatized prior to analysis. The full scan limits of detection (LOD), quantitation (LOQ), and linearity were 2.5, 5.0, and 1000 ng/mL, respectively, for 9-carboxy-THC; 37, 75, and 5000 ng/mL for BE; 50, 100, and 2500 ng/mL for the opiates; 0.25, 0.50, and 500 ng/mL for PCP; and 50, 100, and 5000 ng/mL for the amphetamines. The limits of detection (LOD) and limits of quantitation (LOQ) met the minimum criteria for the signal-to-noise (S/N) ratio and spectral match criteria for drug identification. Absolute LODs and LOQs (in ng/mL) for the ITS40 based on single ion monitoring of blank urines were: 0.8 and 2.0 for 9-carboxy-THC; 8.9 and 25 for BE; 3.3 and 9.6 for codeine; 6.2 and 16.7 for morphine; 0.25 and 0.32 for PCP; 0.7 and 2.0 for amphetamine; and 2.4 and 5.7, for methamphetamine, respectively. The coefficient of variation ranged from 5 to 10%, and analytical recoveries were in the range of 90-114%. The ion trap mass spectrometer permits full scan identification of drugs while maintaining analytical LOQ that are below NIDA guidelines, and has equivalent or better detection limits to quadrupole analyzers for high sensitivity applications.