Utility of immunoassay in drug screening in skeletal tissues: sampling considerations in detection of ketamine exposure in femoral bone and bone marrow following acute administration using ELISA

Detection of ketamine exposure in skeletal tissues by automated enzyme-linked immunosorbent assay (ELISA) and gas chromatography with electron capture detection (GC-ECD) is described. Rats (n = 18) received 0, 15, 30, or 75 mg/kg ketamine hydrochloride acutely (i.p.), and were euthanized within 15 min or 1 h. Ketamine was extracted from ground femoral bone by methanolic incubation followed by liquid-liquid extraction (LLE), while marrow was homogenized in alkaline solution, and then underwent LLE. Extracts were analyzed by ELISA, and subsequently by GC-ECD following derivatization with trifluoroacetic acid anhydride. The effect of tissue type (i.e., diaphyseal bone vs. epiphyseal bone vs. bone marrow) on the immunoassay response was examined through determination of binary classification test sensitivity (S) and measurement of the relative decrease in absorbance (%DA, drug-positive tissues vs. drug-free controls) in each tissue type. The %DA varied significantly between different tissues examined under a given dose condition, and generally decreased in the order marrow > epiphyseal bone > diaphyseal bone, at all dose levels examined. Measured S values for marrow, epiphyseal bone, and diaphyseal bone were 100%, 77%, and 23%, respectively (75 mg/kg dose). These results suggest that the type of skeletal tissue sampled and position sampled within a given bone (diaphyses vs. epiphyses) are important parameters in drug screening of skeletal tissues.     

Detection of acute fentanyl exposure in fresh and decomposed skeletal tissues part II: The effect of dose–death interval

The effects of dose–death interval on the detection of acute fentanyl exposure in fresh and decomposed skeletal tissues (marrow and bone), by automated enzyme-linked immunosorbent assay (ELISA) are described. Rats (n = 14) were administered fentanyl acutely at a dose of 0 (n = 2) or 60 μg/kg (n = 12) by intraperitoneal injection, and euthanized within 20, 45, 135, or 225 min. Femora and tibiae were extracted from the fresh corpses and marrow was isolated from the femoral and tibial medullary cavities. The remains were then allowed to decompose outdoors to the point of complete skeletonization, and vertebrae, pelvi and miscellaneous (humeri and scapulae) were recovered for analysis. In all cases, bones were cleaned in alkaline solution and then ground into a fine powder. Marrow was homogenized in alkaline solution. Fentanyl was extracted from ground bone by methanolic extraction. Extracts were adjusted to pH 6 and analyzed by ELISA. Perimortem heart blood was also collected and diluted in phosphate buffer prior to screening by ELISA. The effect of tissue type on ELISA response was examined through determination of binary classification test sensitivity and the relative decrease in absorbance (%DA, drug-positive tissues vs. drug-free controls) in each tissue type. Overall, the %DA varied significantly between extracts from different skeletal tissues at a given dose–death interval, according to the general order of marrow > decomposed bone > fresh bone. Binary classification test sensitivity values for fentanyl in marrow, fresh epiphyseal (femoral and tibial) bone, fresh diaphyseal (femoral and tibial) bone, decomposed vertebrae, decomposed pelvic bone, and decomposed miscellaneous bone were 67–100%, 0–33%, 0–33%, 0–67%, 0–67% and 0–33%, respectively, over all dose–death intervals. Although group mean %DA values showed a strong negative correlation with dose–death interval in marrow, fresh epiphyseal bone, decomposed vertebrae, pelvic and miscellaneous bone (r = ?0.989, ?0.930, ?0.955, ?0.903, and ?0.974, respectively), the high variability in both fresh and decomposed bone precluded differentiation of the dose–death intervals based on %DA value alone. Overall, the results suggested that the type of skeletal tissue sampled may not be as important as the amount of residual marrow remaining in skeletonized remains.     

Detection of benzodiazepines in different tissues, including bone, using a quantitative ELISA assay.

Benzodiazepines were analyzed in different tissue samples, including hone, by ELISA. The sensitivity of detection for different benzodiazepines was consistent with the manufacturer's reports of the cross reactivities of the antibodies used, with the greatest sensitivity for midazolam and the least for diazepam; in addition the pharmacokinetics was consistent with the known duration of action of the different benzodiazepines, with midazolam cleared rapidly, and diazepam slowly. Following intramuscular injection of 300 microg of midazolam at 16 h intervals for ten days, the drug was detectable in bone tissue samples obtained from skeletonized remains buried in soil at room temperature for three weeks.     

Examination of the effect of dose-death interval on detection of meperidine exposure in decomposed skeletal tissues using microwave-assisted extraction

The effect of dose-death interval and tissue distribution on the detection of meperidine in selected skeletal tissues was examined using a rapid microwave-assisted extraction (MAE) methodology. Rats (n=14) were dosed with 0 (n=2) or 30 mg/kg (n=12) meperidine (i.p.). Drug-positive rats were sacrificed with CO(2) after 20, 30, 90 and 150 min (n=3 per group). Heart blood was collected immediately after death. Tibiae were excised and frozen for further analysis. The remaining carcasses were allowed to decompose outside in secured cages to the point of complete skeletonization in a rural Northern Ontario location during the late summer months. Vertebrae and pelvi were collected for each animal. Tibial marrow was homogenized in 3 mL PB6 (phosphate buffer, 0.1M, pH 6). Fresh tibiae, and decomposed vertebrae and pelvi were cleaned in PB8.5 (phosphate buffer, 0.1M, pH 8.5) and sonicated to remove remaining soft tissue. Samples of dried, ground bone (0.5-1g) suspended in 2 mL PB6 were then irradiated in a domestic microwave oven (1100 W) at atmospheric pressure for 15 min. Samples of vertebral bone (1g) were also extracted by passive incubation in methanol (3 mL, 50°C, 72 h). All supernatants then underwent solid-phase extraction and analysis by GC/MS, using electron impact ionization in the Selected Ion Monitoring (SIM) mode. Mean GC/MS responses for each tissue type were negatively correlated with dose-death interval, with correlation coefficients ranging from -0.32 to -0.87. Analysis of variance showed dose-death interval to be a main effect (p<0.05) with respect to GC/MS response for blood, marrow, tibial epiphyses prepared by MAE, and vertebral bone prepared by passive extraction, but not for tibial diaphyses, pelvi or vertebrae prepared by MAE. Overall, MAE is advantageous as a rapid extraction tool for screening purposes in skeletal tissues, but assignment of significance to quantitative expressions of skeletal drug concentrations is complex and should be approached with caution.     

LC／MS／MS法测定生物组织中百草枯

目的建立LC／MS／MS检测生物体液中百草枯方法。方法弱阳离子交换固相萃取小柱提取剂，应用LC／MS／MS法对生物样品中百草枯进行定性定量分析。结果经该方法测得百草枯的最小检出限为10ng／ml血（S／N≥3），线性范围为0．02～20μg／ml。结论该方法快速、灵敏、准确，适用于生物检材中百草枯的分析。     

Detection of gamma-hydroxybutyrate (GHB) in beverages

OBJECTIVE: To establish an analytical method for the determination of GHB in beverages using GC/MS and LC/MS/MS. METHODS: After beverage samples with GHB-d6 as the internal standard were extracted with ethyl acetate, then the extracts were derivatized with N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA), at last the derivateized extracts analyzed by gas chromatography- mass spectrometry. After beverage samples with GHB-d6 as the internal standard were diluted by mobile phase then directly analyzed by LC/MS/MS. Results The limit of detection was 0.2 microg/mL and both relative standard deviations for between-day and within-day assays were < 8.54% in GC/MS. The limit of detection was 2 microg/mL and both relative standard deviations for between-day and within-day assays were <8.62% in LC/MS/MS. Conclusion These methods of qualitative and quantitative analysis were found to be sensitive, accurate, rapid and suitable for the forensic toxicology to test of GHB in real cases.     

Determination of Nicotine,Cotinine and Trans‐3′‐Hydroxycotinine using LC/MS/MS in Forensic Samples of a Nicotine Fatal Case by Oral Ingestion of e‐cigarette Liquid,

Nicotine is a potent neurotoxin alkaloid and is used in e‐cigarette liquid. The LC/MS/MS method was linear over 0.01–1.0 mg/L (r² = 0.992–0.995). Limit of detection and limit of quantitation were 0.001 mg/L (S/N = 3) and 0.003 (S/N = 10). The inaccuracy and imprecision were <13.2%. The recoveries were >99.3%. A 39‐year‐old dentist was found dead lying on the floor under the couch in his dental clinic. The concentration of nicotine, cotinine, and trans‐3′‐hydroxycotinine (heart blood/peripheral blood) was analyzed as follows: 87.2/85.2 mg/L (ratio 1.0), 1.4/1.1 mg/L (ratio 1.3), and 0.012/0.0089 mg/L (ratio 1.3), respectively. The concentration of nicotine was determined to be 6734.8 mg/kg in gastric contents and 7262.0 mg/L in remaining e‐liquid. Only, high concentration of nicotine was detected in the gastric contents as well as the two pieces of evidence collected from the death scene. This fatal case resulted from oral ingestion of e‐cigarette liquid. It is estimated that at least 714 mg of nicotine was orally ingested.     

Analytical Challenge in Postmortem Toxicology Applied to a Human Body Found into a Lake after Three Years Immersion

The body of a 30‐year‐old woman was found in Como lake at a depth of about 120 meters in her own car after 3 years of immersion. The aim of this study was to evaluate psychoactive drugs as well as alcohol biomarkers in biological matrices. The following analyses were initially performed: GC‐MS systematic toxicological analysis on biological fluids and tissues; GC‐MS analysis of drugs of abuse on pubic hair; direct ethanol metabolite determination in pubic hair by LC‐MS/MS. After 7 years, the samples, that had been stored at ?20°C, were re‐analyzed and submitted to an LC‐MS/MS targeted screening method, using multiple reaction monitoring mode. These analyses detected citalopram (150–3000 ng/mL), desmethylcitalopram (50–2300 ng/mL), clotiapine (20–65 ng/mL), and ethyl glucuronide (97 pg/mg). The methods showed an acceptable reproducibility, and the concentrations of citalopram and desmethylcitalopram calculated through the two analytical techniques did not significantly differ in biological fluids.     

X‐ray Scattering Evaluation of Ultrastructural Changes in Human Dental Tissues with Thermal Treatment

Micro‐ and ultrastructural analysis of burned skeletal remains is crucial for obtaining a reliable estimation of cremation temperature. Earlier studies mainly focused on heat‐induced changes in bone tissue, while this study extends this research to human dental tissues using a novel quantitative analytical approach. Twelve tooth sections were burned at 400–900°C (30‐min exposure, increments of 100°C). Subsequent combined small‐ and wide‐angle X‐ray scattering (SAXS/WAXS) experiments were performed at the Diamond Light Source synchrotron facility, where 28 scattering patterns were collected within each tooth section. In comparison with the control sample, an increase in mean crystal thickness was found in burned dentine (2.8‐fold) and enamel (1.4‐fold), however at a smaller rate than reported earlier for bone tissue (5–10.7‐fold). The results provide a structural reference for traditional X‐ray scattering methods and emphasize the need to investigate bone and dental tissues separately to obtain a reliable estimation of cremation temperature.     

Human Electrical Muscular Incapacitation and Effects on QTc Interval

Human Electrical Muscular Incapacitation (HEMI) is used to subdue combative individuals. Changes in cardiac electrical activity have been proposed as the cause of death in a small fraction of these individuals. The current study sought to determine whether changes in QTc interval occur after HEMI exposure. Twenty‐four participants had EKG readings before a 5‐second HEMI exposure and within 30 min after exposure. All subject EKGs were read by a data‐blinded cardiac electrophysiologist who calculated a QT corrected (QTc) interval. QTc interval was calculated using Bazett method. QTc prolongation was defined as >430 ms and a threshold of 30 ms for identifying QTc lengthening. Five participants experienced QTc prolongation and six had QTc lengthening. One participant developed QTc prolongation exceeding 500 ms, which carries a risk of developing multifocal ventricular tachycardia. These results suggest that HEMI exposure may cause EKG changes with a risk of ventricular tachycardia.     

Quantitative Analysis of Gamma‐Hydroxybutyrate at Endogenous Concentrations in Hair using Liquid Chromatography Tandem Mass Spectrometry

Abstract: A method capable of quantifying endogenous concentrations of gamma‐hydroxybutyrate (GHB) in human head hair was developed and validated using liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS). Hair was digested under alkaline conditions, and GHB was isolated using liquid–liquid extraction. LC/MS/MS was performed using atmospheric pressure chemical ionization in the negative mode, multiple reaction monitoring, and deuterated internal standard (GHB‐D₆). Linearity was observed between 0.1 and 100 ng/mg GHB (R² = 1.000). The limits of detection and quantitation in human hair were 0.2 and 0.4 ng/mg, respectively. Accuracy at 2 ng/mg and 10 ng/mg was determined to be 97% and 94%, and intra‐assay CVs at these concentrations were 5.2% and 7.4% (n = 4). Beta‐hydroxybutyrate (BHB), alpha‐hydroxybutyrate, gamma‐butyrolactone, and 1,4‐butanediol did not produce an interference, and there was negligible ion suppression or enhancement from the matrix.     

Teens and Spice: A Review of Adolescent Fatalities Associated with Synthetic Cannabinoid Use

Synthetic cannabinoids (SCs) are commonly abused by adolescents with reported past year (2013) use in high school students between 3 and 10%. Standard adolescent postmortem toxicology does not include routine SC analysis, and thus, the true burden of fatalities related to SCs is unknown. A retrospective case review of two cases included scene investigation, interviews, autopsy, and toxicology. SCs were confirmed by liquid chromatography–tandem mass spectrometry (LC?MS/MS). Review of the eight adolescent SC‐associated fatalities in the literature revealed five of eight cases had no other discernible cause of death on autopsy. Compounds detected included PB‐22 (1.1 ng/mL), JWH‐210 (12 ng/mL), XLR‐11 (1.3 ng/mL), JWH‐122, AB‐CHMINACA (8.2 ng/mL), UR‐144 (12.3 ng/mL), and JWH‐022 (3 ng/mL). With synthetic drug use on the rise, forensic experts should have a high index of suspicion for the possibility of SC intoxication in adolescent fatalities with no other discernible cause of death.     

Alprazolam and Zolpidem in Skeletal Tissue of Decomposed Body Confirms Exposure

In several medico‐legal cases, bone samples analysis may provide the only source of toxicological information. This case study reports the analysis of a human bone specimen, belonging to a 46‐year‐old man, found 3 months after his death due to cervical–thoracic injuries in a motorcycle accident. Bone specimen was the only available material for toxicological analysis, among few skull hair and rotten skin. Analysis was performed by a newly developed and validated ultra‐high‐pressure liquid chromatography–mass spectrometry/mass spectrometry (UHPLC‐MS/MS) method, following simple and efficient sample pretreatment. The results were in accordance with the man's medical record: Alprazolam and zolpidem were found at 2.2 and 5.4 ng/g of bone, respectively. Both these drugs were prescribed to the deceased.     

Detection of toluene in an adipoceratous body

A 24-year-old male was found dead in a car left in a river for about 3 months. The cadaver was almost adipoceratous and autopsy findings revealed that there were neither remarkable injuries nor lethal diseases. Toluene, ethanol, 1-propanol, 2-propanol, 1-butanol, dimethyl sulfide, dimethyl disulfide, isovaleraldehyde and n-butyl n-butyrate were detected in the specimens collected at the autopsy by head space gas chromatography/mass spectrometry (GC/MS). The toluene concentrations (μg/g) were 31.0 in brain, 10.6 in liver, 5.4 in kidney, 15.0 in skeletal muscle and 187.1 in adipose tissue. The presence of diatom in lung, liver and kidney suggested that death was caused by drowning. So far as we know, this is the first report of detection of toluene in an adipoceratous body.     

Identification of selected psychopharmaceuticals and their metabolites in hair by LC/ESI-CID/MS and LC/MS/MS

Hair samples of patients of psychiatry and hair samples of suicide cases were analysed by liquid-chromatography/ionspray-mass spectrometry (LC/MS) for antidepressants and neuroleptics. Electrospray ionisation (ESI) with in-source collision induced dissociation (ESI/CID) and tandem-mass spectrometry (MS/MS) were used for drug and metabolite identification. Mass spectra library searching was performed using an ESI/CID mass spectra library and a MS/MS spectra library. Furthermore, extracted ion chromatograms were used for the detection of N-desmethyl-metabolites, which were also identified by their fragment-ion spectra. Three examples using these methods are shown: The tricyclic antidepressant maprotiline, the selective serotonin receptor inhibitor (SSRI) citalopram and their desmethylmetabolites as well as the neuroleptic pipamperone were detected and identified in hair extracts. For extraction powdered hair was treated by ultrasonication in methanol and solid-phase extraction was used for sample clean-up prior to LC/MS or MS/MS analysis. These examples demonstrate the power of LC/MS and LC/MS/MS for the detection and identification of drugs in hair extracts using full-scan mode and ESI/CID with library searching or using highly selective LC/MS/MS-analysis with library searching or in multiple reaction monitoring mode.     

A Comparison Between Digital Radiography,Computed Tomography,and Magnetic Resonance in the Detection of Gunshot Residues in Burnt Tissues and Bone

The radiological search for GSR is crucial in burnt material although it has been rarely tested. In this study, thirty‐one bovine ribs were shot at near‐contact range and burnt to calcination in an oven simulating a real combustion. Computed tomography (CT) and magnetic resonance (MR) were performed before and after carbonization and compared with former analyses with DR (digital radiography); thus comparing the assistance, the radiological methods can provide in the search for GSR in fresh and burnt bone. DR demonstrated the greatest ability in the detection of metallic residues, CT showed lower abilities, while MR showed a high sensitivity only in soft tissues. Thus, DR can be considered as the most sensitive method in the detection of GSR in charred bones, whereas CT and MR demonstrated much less reliability. Nonetheless, the MR ameliorates the analysis of gunshot wounds in other types of remains with large quantities of soft tissues.     

Quantitation of Synthetic Cannabinoids in Plant Materials Using High Performance Liquid Chromatography with UV Detection (Validated Method)

Plant based products laced with synthetic cannabinoids have become popular substances of abuse over the last decade. Quantitative analysis for synthetic cannabinoid content in the laced materials is necessary for health hazard assessments addressing overall exposure and toxicity when the products are smoked. A validated, broadly applicable HPLC‐UV method for the determination of synthetic cannabinoids in plant materials is presented, using acetonitrile extraction and separation on a commercial phenylhexyl stationary phase. UV detection provides excellent sensitivity with limits of quantitation (LOQs) less than 10 μg/g for many cannabinoids. The method was validated for several structural classes (dibenzopyrans, cyclohexylphenols, naphthoylindoles, benzoylindoles, phenylacetylindoles, tetramethylcyclopropylindoles) based on spike recovery experiments in multiple plant materials over a wide cannabinoid contents range (0.1–81 mg/g). Average recovery across 32 cannabinoids was 94% for marshmallow leaf, 95% for damiana leaf, and 92% for mullein leaf. The method was applied to a series of case‐related products with determined amounts ranging from 0.2 to >100 mg/g.     

Morbidity Involving the Hallucinogenic Designer Amines MDA and 2C‐I*

Abstract: A case is presented of a 39‐year‐old woman who suffered severe debilitation because of a hemorrhagic stroke in the context of substance abuse. The patient presented to the emergency room with rapidly diminishing mental status, hypertension, and vasoconstriction; her friends provided a history of ingestion of cocaine, 3,4‐methylenedioxymethamphetamine (MDMA), and 2C‐I, a novel designer amine. A multi‐targeted LC‐MS/MS method for sympathomimetic amines and related drugs in urine detected and quantified 2C‐I and MDA, while ruling out MDMA. The cause of the stroke was determined to be an underlying cerebrovascular abnormality called Moyamoya, secondary to substance abuse. In clinical laboratories, gas chromatography–mass spectrometry or liquid chromatography–tandem mass spectrometry (LC‐MS/MS) confirmation of a positive amphetamine immunoassay is usually directed only towards amphetamine, methamphetamine, MDMA and MDA. This report demonstrates the utility of testing for a wider menu of compounds using LC‐MS/MS in order to better characterize the prevalence and toxicities of novel amines such as 2C‐I.     

Validation of an LC–MS Method for the Detection and Quantification of BZP and TFMPP and their Hydroxylated Metabolites in Human Plasma and its Application to the Pharmacokinetic Study of TFMPP in Humans*

Abstract: An LC–MS method was developed for benzylpiperazine (BZP) and trifluoromethylphenylpiperazine (TFMPP), constituents of “party pills” or “legal herbal highs,” and their metabolites in human blood plasma. Compounds were resolved using a mixture of ammonium formate (pH 4.5, 0.01 M) and acetonitrile (flow rate of 1.0 mL/min) with a C18 column. Calibration curves were linear from 1 to 50 ng/mL (R² > 0.99); the lower limit of quantification (LLOQ) was 5 ng/mL; the accuracy was >90%; the intra‐ and interday relative standard deviations (R.S.D) were <5% and <10%, respectively. Human plasma concentrations of TFMPP were measured in blood samples taken from healthy adults (n = 6) over 24 h following a 60‐mg oral dose of TFMPP: these peaked at 24.10 ng/mL (±1.8 ng/mL) (C_max) after 90 min (T_max). Plasma concentrations of 1‐(3‐trifluoromethyl‐4‐hydroxyphenyl) piperazine peaked at 20.2 ng/mL (±4.6 ng/mL) after 90 min. TFMPP had two disposition phases (t_½ = 2.04 h (±0.19 h) and 5.95 h (±1.63 h). Apparent clearance (Cl/F) was 384 L/h (±45 L/h).