Longitudinal evaluation of fentanyl concentrations in equine plasma and synovial fluid following application of transdermal fentanyl patches over one carpal joint.

OBJECTIVE: To determine if transdermally delivered fentanyl can achieve greater concentrations of fentanyl in synovial fluid when applied over a synovial structure. STUDY DESIGN: Randomized, experimental study. ANIMALS: Six healthy adult horses. METHODS: Each horse had two 100 µg/h fentanyl matrix patches applied on the dorsal aspect of one, randomly assigned, carpometacarpal joint (CMCJ) for 48 h. Whole blood and bilateral synovial samples from the intercarpal joint were obtained at 0, 2, 6, 12, 24, 36 and 48 h. Fentanyl concentrations were measured with liquid chromatography-mass spectrometry. RESULTS: All subjects achieved detectable concentrations of fentanyl in both plasma and synovial fluid. Time to peak synovial and plasma concentration was 12 h. At 6 h, the synovial concentration in the untreated carpus (0.104 ng/mL ± 0.106) was lower than plasma fentanyl concentrations 0.31 ± 0.27 (p = .036). At 12 h, both treated (0.55 ng/mL ± 0.3) and untreated (0.53 ng/mL ± 0.28) synovial fluid fentanyl concentrations were lower than plasma (0.87 ng/mL ± 0.48) concentrations (p < .001 and p = .001, respectively). Synovial concentrations of fentanyl did not differ between treated and untreated joints (p > 0.608 for all time points). CONCLUSION: Application of fentanyl matrix patches directly over the CMCJ did not result in increased fentanyl concentrations in the synovial fluid of the treated intercarpal joint in normal horses. CLINICAL SIGNIFICANCE: There is likely no analgesic advantage to placing fentanyl patches directly over the affected joint, as it did not result in increased synovial concentrations at the tested site.

Detection and confirmation of fentanyls in high clay-content soil by electron ionization gas chromatography-mass spectrometry.

Detection of illicit drugs in the environment, particularly in soils, often suggests the present or past location of a clandestine production center for these substances. Thus, development of efficient methods for the analysis and detection of these chemicals is of paramount importance in the field of chemical forensics. In this work, a method involving the extraction and retrospective confirmation of fentanyl, acetylfentanyl, thiofentanyl, and acetylthiofentanyl using trichloroethoxycarbonylation chemistry in a high clay-content soil is presented. The soil was spiked separately with each fentanyl at two concentrations (1 and 10 µg/g) and their extraction accomplished using ethyl acetate and aqueous NH4 OH (pH ~ 11.4) with extraction recoveries ranging from ~56% to 82% for the high-concentration (10 µg/g) samples while ranging from ~68% to 83% for the low-concentration (1 µg/g) samples. After their extraction, residues containing each fentanyl were reacted with 2,2,2-trichloroethoxycarbonyl chloride (Troc-Cl) to generate two unique and predictable products from each opioid that can be used to retrospectively confirm their presence and identity using EI-GC-MS. The method's limit of detection (MDL/LOD) for Troc-norfentanyl and Troc-noracetylfentanyl were estimated to be 29.4 and 31.8 ng/mL in the organic extracts. In addition, the method's limit of quantitation for Troc-norfentanyl and Troc-noracetylfentanyl were determined to be 88.2 and 95.5 ng/mL, respectively. Collectively, the results presented herein strengthen the use of chloroformate chemistry as an additional chemical tool to confirm the presence of these highly toxic and lethal substances in the environment.

Fentanyl pharmacokinetics in blood of cancer patients by Gas Chromatography - Mass Spectrometry.

In order to find a correlation between Fentanyl action on pain and inter-individual variability in different cancer patients, the pharmacokinetic characterization of the drug becomes essential. Therefore, a gas chromatographic-mass spectrometric (GC-MS) in SIM mode analytical procedure has been developed and validated for the determination of Fentanyl in human blood. The sample preparation consisted of a liquid-liquid extraction (LLE) from whole blood. The analysis were carried out with Agilent 7820 A series gas chromatograph equipped with a 5977E series mass selective single quadrupole detector (MSD) with an electron impact (EI) source (70 eV), under a temperature gradient elution. The limit of detection (LoD) and the limit of quantification (LoQ) values were found to be 5.60E-02 ± 3.50E-02 ng mL-1 and 1.86E-01 ± 1.18E-01 ng mL-1 respectively. The developed method was found selective and sensitive and therefore suitable for a fast determination of Fentanyl in human blood and for its pharmacokinetic characterization. Blood samples from 31 cancer patients treated with transdermal Fentanyl (doses in the range of 12-100 µg h-1) were collected at fixed intervals during an overall exposure time of 72 h. The analysis of data and the pharmacokinetic parameters revealed dissimilar pharmacokinetic profiles in the patients examined. Patients were therefore grouped in three categories representing the different trends observed: high, medium and slow responders. These preliminary data provided significant outcomes for a correlation to clinical response.

Accidental Occupational Exposure to a Large Volume of Liquid Fentanyl on a Compromised Skin Barrier with No Resultant Effect.

The high prevalence of fentanyl in the illicit drug supply has generated concern among first responders regarding occupational exposure. Social media sharing of unconfirmed first responder overdoses after brief exposure to fentanyl may be contributing to an inappropriate risk perception of brief dermal fentanyl exposure. This case details a dermal exposure to a large dose of analytically confirmed pharmaceutical fentanyl (fentanyl citrate, 10 microgram fentanyl base per ml), over a large skin surface area. Additionally, the exposure occurred at a site with some skin barrier compromise, a factor that can increase fentanyl absorption. The patient underwent appropriate decontamination and underwent a brief medical assessment with no clinical effects of opioid exposure observed. This information is of value to first responders and other health care workers who are at risk of occupational fentanyl exposure. Findings are consistent with in vitro and ex vivo data supporting low risk of rapid absorption after brief dermal fentanyl exposure.

11-Year Study of Fentanyl in Driving Under the Influence of Drugs Casework†.

Prior to 2017, heroin and other prescription opioids were the most prevalent opioids implicated in driving under the influence of drugs (DUID) investigation cases, and fentanyl was rarely included in the scope of toxicological analysis. Fentanyl has become the most frequently identified opioid in DUID cases, with many suspected heroin cases turning out to be only fentanyl. A review of fentanyl-positive DUID cases at NMS Labs was performed to provide prevalence information, change in concentration, patterns of combined drug use, indicators of impairment and driving behavior in order to assist with the toxicological interpretation of DUID scenarios involving fentanyl. Fentanyl-positive DUID cases received between January 2010 and December 2020 were examined. Blood results were confirmed and quantitated for fentanyl, norfentanyl and acetylfentanyl using a liquid chromatography--tandem mass spectrometry analysis with a limit of quantitation of 0.10, 0.20 and 0.10 ng/mL, respectively. Of 153,234 blood cases examined for DUID over 11 years, fentanyl was confirmed positive in 6,779 (4.4%) cases. However, there were significant changes in positivity over time. Fentanyl percentage positivity increased from 0.60% in 2010 to 12% in 2020. Of 5,976 confirmed fentanyl-positive cases in 2018-2020, blood concentrations >4.0 ng/mL were observed in 44% (2018), 55% (2019) and 59% (2020) of cases. Polypharmacy was common with 87% of blood samples confirmed positive for fentanyl and at least one other compound. Stimulant was the most commonly identified drug class in cases where at least one additional drug class was present. This study illustrates the importance of including fentanyl in a routine blood DUID panel.

Gas Chromatography-Mass Spectrometry Analysis of Synthetic Opioids Belonging to the Fentanyl Class: A Review.

The rising number of deaths caused by fentanyl overdosing in the US due to the overwhelming illicit use of this synthetic opioid has started a global campaign to develop efficient ways to control its production and distribution as well as discovering efficient antidotes to mitigate its lethal effects. Another important vein of focused research established by various agencies lies in the development of efficient and practical protocols for the detection of this opioid and analogs thereof in various matrices, whether environmental or biological in nature, particularly in the field of gas chromatography-mass spectrometry (GC-MS). The following review will cover the literature dealing with the detection and identification of synthetic opioids belonging to the fentanyl class by GC-MS means and hyphenated versions of the technique. Detailed descriptions will be given for the GC-MS methods employed for the analysis of the opioid, starting with the nature of the extraction protocol employed prior to analysis to the actual findings presented by the cited reports. Great effort has gone into describing the methods involved in each paper in a detailed manner and these have been compiled by year in tables at the end of each section for the reader's convenience. Lastly, the review will end with concluding remarks about the state of GC-MS analysis with regards to these powerful opioids and what lies ahead for this analytical field.

Effect of positive urine fentanyl screen on attitudes toward heroin use.

BACKGROUND: It is unknown if targeted risk reduction counseling in the health care setting, after documented exposure to fentanyl, can affect behavior change to reduce risks and increase utilization of evidence-based overdose prevention strategies. METHODS: We conducted a retrospective analysis of results (7/2018-6/2019) from questionnaire-facilitated counseling by recovery coaches in the emergency department (ED) and primary care settings following disclosure of a urine toxicology positive for fentanyl. RESULTS: Seventy-five percent of N = 101 respondents were neither aware of nor expecting fentanyl in their substances of use. Fifty-three (70 %) of those initially unaware answered that learning about exposure to and the risks from fentanyl changed their thoughts about reducing or abstaining from use. A greater proportion of patients seen in the ED expressed desire to stop or reduce opioid use as compared to ambulatory clinic patients (91 % vs. 46 %, p < 0.001). Of those not already engaged in treatment, 18 % and 15 % were interested in medication and behavioural health treatment, respectively, and each of them indicated a change in thought based on the counseling. Forty-five percent of individuals not yet receiving naloxone endorsed interest in receiving it, and 22 % of all respondents were somewhat or very interested in access to safe consumption sites. CONCLUSION: This study suggests a novel clinical utility in toxicology screens to inform behavior in the setting of illicit fentanyl exposure. In addition to linkages to evidence-based treatment, linkages to harm-mitigating strategies associated with ongoing substance use may be critical to a comprehensive overdose prevention strategy in the clinical setting.

Hitting the Jackpot - development of gas chromatography-mass spectrometry (GC-MS) and other rapid screening methods for the analysis of 18 fentanyl-derived synthetic opioids.

In recent years, the occurrence of synthetic opioid fentanyl and its derivatives has grown significantly in forensic casework. This study presents the synthesis and analysis of 18 fentalogs, selected based on information received from local law enforcement. This study provides colorimetric tests, thin-layer chromatography (TLC) which can potentially be utilized for presumptive screening of the target compounds, as bulk powders or as trace-level adulterants. The fully validated confirmatory GC-MS method (employing SIM mode) allows the identification of the 18 derivatives, five commonly encountered controlled substances and four adulterants, within 20 minutes. The cross-validated method described herein provides a sensitive screening and quantitation method for the illicit (and potentially harmful) components at trace levels (LOD = 0.007-0.822 µg/mL and LOQ = 0.023-2.742 µg/mL respectively). Spectral data [1 H-NMR, 13 C-NMR, 19 F-NMR, FT-IR, and HRMS] and assignments for the synthesized reference materials are also provided in the Supplementary Information for laboratories engaged in the routine analysis of fentanyl and its derivatives.

Fatal misuse of transdermal fentanyl patches.

Fentanyl is a potent synthetic opioid with a variety of possible applications. Transdermal fentanyl patches are regularly prescribed for patients with severe chronic or cancer-related pain. The potential for abuse is well-known and cases associated with illicit fentanyl intake are common. Fentanyl related fatalities due to unintentional misuse are relatively rare. This study focused on those instances and their identification in forensic examinations and adds new cases and consolidates the existing femoral blood concentrations in the event of fatal fentanyl patch misapplications. A total of 35 cases between 2010 and 2018 in which transdermal fentanyl patches were detected during forensic autopsies were identified and reviewed for the frequency of unspecific macroscopic signs of opioid intoxication. Furthermore, a detailed examination is presented for 11 cases in which toxicological results were available. The cause of death was eventually considered to be related to fentanyl patch misuse in 5 of these 11 cases. Co-administered drugs and signs of opioid intoxication, especially pulmonary edema, were frequently found. Lastly, it is advised to include norfentanyl and hair analysis in the interpretation of post-mortem fentanyl concentrations.

Gas chromatography with tandem cold electron ionization mass spectrometric detection and vacuum ultraviolet detection for the comprehensive analysis of fentanyl analogues.

Fentanyl and its derivatives are amongst the ever-growing list of emerging drugs which are impinging on current traditional analytical techniques employed in forensic laboratories. To avoid current regulations, fentanyl analogues are being illicitly synthesized by slight alterations of functional groups to the fentanyl skeleton leading to inaccurate identifications, thus posing the greatest challenge to laboratories. In this study, a novel analytical technique is presented in which gas chromatography (GC) is interfaced with both cold electron ionization mass spectrometric (cold EI MS) and vacuum ultraviolet (VUV) detection by the means of a flow splitter for the simultaneous qualitative and quantitative analysis of twenty-four fentanyl analogues, including seven sets of positional isomers. For most of the twenty-four analogues, enhanced molecular ions were obtained with at least 1% intensity relative to base peak. In addition to enhanced molecular ions, the GC-cold EI MS maintained fragmentation pathways observed by GCMS with classical electron ionization. For the most part, VUV detection resulted in unique VUV spectra for fentanyl analogues including positional isomers. The combination of these two complementary detectors in tandem with the high resolving power of the gas chromatograph, allows for higher confidence in analyte identification by the combination of retention times, cold EI mass spectra and VUV spectra. The preferred method for quantitation was based on VUV detection and offered excellent determination coefficients (R2≥0.999) for most analytes over two orders of magnitude dynamic range, without the need for deuterated internal standards. For both run-to-run and day-to-day repeatability studies, at moderate solute concentrations, the correct fentanyl related compound was identified in almost every instance from a library containing all the fentanyl analogues plus hundreds of other analytes.

Testing hair for fentanyl exposure: a method to inform harm reduction behavior among individuals who use heroin.

BACKGROUND: Deaths from fentanyl exposure continue to increase in the US. Fentanyl test strips are now available to test urine for presence of fentanyl, but additional testing methods are needed to determine past exposure and to determine exposure to specific analogs. OBJECTIVES: To investigate exposure to such analogs through hair testing. METHODS: Forty individuals in inpatient detoxification (7.5% female) reporting past-month heroin use were surveyed and provided a hair sample to be tested at a later date. While results could not be provided to patients, they were asked how they would respond if informed that their hair tested positive for fentanyl. UHPLC-MS/MS was used to test for past exposure to fentanyl, six other novel synthetic opioids, and fentanyl biomarkers/metabolites. RESULTS: 27.5% reported known fentanyl use in the past year and 67.5% reported suspected exposure. 97.5% (39 of 40) tested positive for fentanyl, 90.0% tested positive for 4-ANPP (a biomarker) and norfentanyl (a metabolite); 82.5% tested positive for acetyl-fentanyl, 47.5% tested positive for furanyl-fentanyl, and 7.5% tested positive for U-47700. Most participants (82.5%) reported they would warn others about fentanyl if they learned their hair tested positive; 75.0% reported they would try to stop using heroin, and 65.0% reported they would ensure that someone nearby has naloxone to reverse a potential overdose. CONCLUSIONS: Hair testing is useful in detecting past exposure to fentanyl, its analogs, and other novel synthetic opioids. Further research is needed to determine whether individuals who use heroin learning about exposure affects drug-taking and treatment-seeking behavior.

Sensitive Determination of Fentanyl in Low-Volume Serum Samples by LC-MS/MS.

Fentanyl is a widely used drug in the management of pain. Present LC-MS/MS methods for analysis of fentanyl require a large volume of serum, but yet the sensitivity was at about 50 pg/mL. Here, we report a modified liquid-liquid extraction method for the analysis of fentanyl in serum. The method is very sensitive with a LLOQ of 5 pg/mL while using only 0.175 mL of serum for analysis. The separation was performed on a Zorbax XDB-C18 column (4.6 × 50 mm, 1.8 µm, 600 bar) using a mobile phase of water: acetonitrile (70:30 v/v) with 0.1% formic acid that was pumped isocratically at a flow rate of 0.5 mL per minute. The calibration curve was found to be linear over a range of 5-10,000 pg/mL. The inter-day and intra-day accuracy and precision were tested using low (20 pg/mL), medium (1000 pg/mL), and high (5000 pg/mL) quality control samples of fentanyl prepared in blank human serum and were within ± 15% of the nominal value. Fentanyl was also found to be stable in various storage and sample preparation conditions, including short-term bench-top storage (for 5 h), freeze-thaw cycling (three cycles), long-term frozen condition (4.5 months at - 70°C), and post-preparative storage (for 48 h).

Bioanalytical methods for the quantification of hydromorphone, fentanyl, norfentanyl, morphine, morphine-3ß-glucuronide and morphine-6ß-glucuronide in human plasma.

The aim of this study was to develop an assay for the quantification of hydromorphone, morphine, fentanyl and the metabolites norfentanyl, morphine-3ß-glucuronide and morphine-6ß-glucuronide in human plasma to support pharmacokinetic studies investigating the large interpatient variability in response to opioid treatment. For the quantitation of hydromorphone, morphine, fentanyl and its metabolite norfentanyl aliquots of 200µL human potassium EDTA plasma were deproteinized with deuterated internal standards in a mixture of acetonitrile and acetone, followed by a liquid-liquid extraction with 4% ammonium hydroxide and ethyl acetate. Morphine-3ß-glucuronide and morphine-6ß-glucuronide were extracted by a solid phase extraction using 10mM ammonium carbonate pH 8.8 and a deuterated internal standards solution. Morphine, hydromorphone, fentanyl and norfentanyl were separated on an Aquity UPLC® BEH C18 column 1.7µm, 100mm×2.1mm at 50°C. Separation, was achieved on a gradient of methanol with an overall run time of 6min. The compounds were quantified by triple-quadrupole mass spectrometry in the positive ion electrospray ionization mode. Morphine-3ß-glucuronide and morphine-6ß-glucuronide were separated on a VisionHT C18-P; 3µm 2.1×50mm, column at 40°C on a gradient of acetonitrile, with an overall run time of 10min. Both methods were precise and accurate, with within-run and between-run precisions within acceptable limits and accuracy ranging from 84.0 to 105.5%. The methods were successfully applied to support clinical pharmacological studies in patients treated with opioids for the treatment of moderate to severe cancer-related pain.

Echocardiographic parameters in dogs treated with acepromazine and fentanyl / Parâmetros ecocardiográficos em cães tratados com acepromazina e fentanil

Considering that the use of tranquillizers could optimize the performance of the echocardiogram, this study aimed to evaluate the effect of protocols with acepromazine and fentanyl on the echocardiographic parameters of healthy dogs, besides their effect in systolic blood pressure (SBP), respiratory rate (RR), heart rate (HR), time spent for examination and sedation scale. Ten adult dogs were submitted to different tranquilizing protocols 20 minutes before the echocardiographic examination, totalling five treatments for each pair, performed at seven-day intervals between evaluations. The treatments were CT (control treatment), IAT (intramuscular acepromazine), OAT (oral acepromazine), FT (fentanyl) and AFT (acepromazine associated with fentanyl). In addition to the echocardiographic evaluation, SBP, degree of reassurance, duration of the exam, HR and RR in the different protocols were evaluated. There was a significant decrease of SBP in OAT. There was a significant reduction in left ventricular diameter during systole and diastole and mitral annular movement in IAT, OAT and AFT, compared with CT. There was a decrease in tricuspid annular plane systolic excursion and increase in mitral E/mitral A ratio in IAT and OAT when compared with CT. All the tranquillizer protocols studied were found to significantly reduce HR, that facilitated the echocardiographic examination.(AU)

Considerando que o uso de tranquilizantes poderia otimizar a realização do ecocardiograma, objetivou-se com este estudo avaliar o efeito da tranquilização com acepromazina e fentanil sobre os parâmetros ecocardiográficos em cães saudáveis, bem como o efeito na pressão arterial sistólica (PAS), na frequência respiratória (FR), na frequência cardíaca (FC), no tempo gasto para a realização do exame e na escala de sedação. Dez cães adultos foram submetidos a diferentes protocolos tranquilizantes, 20 minutos antes da avaliação ecocardiográfica, totalizando cinco tratamentos para cada dupla, realizados com intervalos de sete dias entre as avaliações. Os tratamentos foram: TC (tratamento controle), TAI (acepromazina intramuscular), TAO (acepromazina oral), TF (fentanil) e TAF (acepromazina associada ao fentanil). Além dos parâmetros ecocardiográficos, foram avaliados a PAS, o grau de tranquilização, o tempo de duração do exame e a FC e a FR nos diferentes protocolos. Houve diminuição significativa da PAS no TAO. Observou-se redução significativa do diâmetro do ventrículo esquerdo em sístole e diástole e do movimento anular de mitral nos protocolos TAI, TAO e TAF, comparados com o TC. Observou-se também uma redução da excursão sistólica do plano anular tricúspide e aumento da relação mitral E/mitral A nos protocolos TAI e TAO quando comparados ao TC. Todos os protocolos de tranquilização reduziram significativamente a FC, o que facilitou a realização do exame.(AU)

In vitro Characterization of NPS Metabolites Produced by Human Liver Microsomes and the HepaRG Cell Line Using Liquid Chromatographyhigh Resolution Mass Spectrometry (LC-HRMS) Analysis: Application to Furanyl Fentanyl.

BACKGROUND: Identification of metabolites is of importance in the challenge of new psychoactive substances (NPS) as it could improve the detection window in biological matrices in clinical and forensic cases of intoxication. Considering the numerous and diverse NPS reported each year, producers increasingly appear today to be targeting non-controlled synthetic opioids, involving fentanyl derivatives such as furanyl fentanyl (Fu-F). OBJECTIVE: This work aims to investigate and compare metabolites of Fu-F using two in vitro experimental approaches. METHODS: CYP- and UGT-dependent metabolites of Fu-F were investigated by means of analyses of both human liver microsome (HLM) and hepatic (HepaRG) cell line incubates using liquid chromatography with high-resolution mass detection and, subsequently, compared and confronted to recently published data. RESULTS: Seventeen Fu-F metabolites were produced and several metabolic pathways can be postulated. HLMs and HepaRG cultures appear to be complementary: HepaRG cells produced 9 additional metabolites, but which appear to be minor in vivo metabolites. Specific* and/or abundant Fu-F metabolites are dihydrodiol-Fu-F*, norFu-F* and despropionylfentanyl. However, norFu-F seems to be inconstantly observed in in vivo cases. Furthermore, a sulfate metabolite presents at significant rate in urine obtained from FU-F users was not identified here, as in another in vitro study. CONCLUSION: HLMs represent an acceptable first choice tool for a single NPS metabolism study in forensic laboratories. Dihydrodiol-Fu-F and despropionylfentanyl could be proposed as reliable metabolites to be recorded in HRMS libraries in order to improve detection of Fu-F users. Nevertheless, additional verifications of in vivo data remain necessary to confirm relevant blood and urinary metabolites of Fu-F.

A Novel Oral Fluid Assay (LC-QTOF-MS) for the Detection of Fentanyl and Clandestine Opioids in Oral Fluid After Reported Heroin Overdose.

INTRODUCTION: The adulteration of heroin with non-pharmaceutical fentanyl and other high-potency opioids is one of the factors contributing to striking increases in overdose deaths. To fully understand the magnitude of this problem, accurate detection methods for fentanyl and other novel opioid adulterant exposures are urgently required. The objective of this work was to compare the detection of fentanyl in oral fluid and urine specimens using liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) in a population of heroin users presenting to the Emergency Department after overdose. METHODS: This was a prospective observational study of adult Emergency Department patients who presented after a reported heroin overdose requiring naloxone administration. Participants provided paired oral fluid and urine specimens, which were prepared, extracted, and analyzed using a dual LC-QTOF-MS workflow for the identification of traditional and emerging drugs of abuse. Analytical instrumentation included SCIEX TripleTOF® 5600+ and Waters Xevo® G2-S QTOF systems. RESULTS: Thirty participants (N = 30) were enrolled during the study period. Twenty-nine participants had fentanyl detected in their urine, while 27 had fentanyl identified in their oral fluid (overall agreement 93.3%, positive percent agreement 93.1%). Cohen's Kappa (k) was calculated and demonstrated moderately, significant agreement (k = 0.47; p value 0.002) in fentanyl detection between oral fluid and urine using this LC-QTOF-MS methodology. Additional novel opioids and metabolites, including norfentanyl, acetylfentanyl, and U-47700, were detected during this study. CONCLUSION: In this study of individuals presenting to the ED after reported heroin overdose, a strikingly high proportion had a detectable fentanyl exposure. Using LC-QTOF-MS, the agreement between paired oral fluid and urine testing for fentanyl detection indicates a role for oral fluid testing in surveillance for nonpharmaceutical fentanyl. Additionally, the use of LC-QTOF-MS allowed for the detection of other clandestine opioids (acetylfentanyl and U-47700) in oral fluid.

Development, validation and application of an HPLC-MS/MS method for the determination of fentanyl and nor-fentanyl in human plasma and saliva.

Monitoring fentanyl concentration in saliva and plasma may be useful in pharmacokinetic/pharmacodynamic studies. Salivettes(®) have been used widely for collecting saliva samples. However due to its lipophilicity, fentanyl adsorbs to the cotton dental bud (CDB) used in this device. Furthermore, due to dry mouth being a common adverse effect seen in patients treated with opioids, obtaining enough saliva for analysis is often a challenge. Hence, a simple simultaneous method to quantify fentanyl and its metabolite in both human plasma and saliva was developed and validated. A novel extraction method was also developed and validated to recover fentanyl in saliva directly from the CDB. This extraction method utilises acetonitrile to recover the fentanyl directly from the CDB rather than recovery by centrifugation, which is not always possible. Reverse phase chromatographic separation was performed on a Shimadzu LC 20A HPLC system using gradient elution. The electrospray ion source (ESI) was operated in positive ion mode using an Applied Biosystems API 3200 LC/MS/MS as detector. Deuterated fentanyl (D5) and nor-fentanyl (D5) were used as internal standards (IS). The retention times for fentanyl and nor-fentanyl were 3.70 min and 3.20 min respectively. The lower limit of quantitation (LLOQ) was determined to be 0.030 µg/L in plasma and 0.045 in saliva for fentanyl and nor-fentanyl. Acceptable linearity for fentanyl and nor-fentanyl in both plasma and saliva was demonstrated from 0.02 to 10 µg/L (R(2) 0.9988-0.9994). Accuracy for fentanyl and nor-fentanyl in both plasma and saliva samples was between 96% and 108%. Total imprecision expressed as the co-efficient of variation was between 1.0 and 15.5% for both analytes in both matrices. The validated method was applied successfully in 11 paired plasma and saliva samples obtained from patients with cancer pain receiving transdermal fentanyl (Duragesic(®)) at doses from 25 µg to 100 µg.

Assisted suicide by fentanyl intoxication due to excessive transdermal application.

Herein, we report a case of an assisted suicide committed by application of 34 matrix-based fentanyl-containing transdermal therapeutic systems (TTS) with different release rates. The TTS were supplied by the husband but administered by the deceased herself. Besides routine systematic toxicological analysis (STA), the concentrations of fentanyl and norfentanyl were determined in the blood (femoral and heart), urine, stomach content, brain, lung tissue, musculus iliopsoas, liver, kidney, bile and in some of the used TTS by LC-MS/MS. Blood levels of fentanyl were 60.6 µg/L in femoral blood and 94.1 µg/L in heart blood. These concentrations are in good concordance with levels described in cases with accidental or lethal suicidal fentanyl patch application. The organ distribution indicates an influence of post-mortem redistribution. The levels of residual fentanyl in the TTS were also determined. STA furthermore revealed supratherapeutic levels of bromazepam. Thus, the cause of death was a combination of fentanyl and bromazepam intoxication. However, considering the determined levels of fentanyl and norfentanyl in the entire set of specimens and the high toxicity in comparison to bromazepam, fentanyl was the leading toxic noxa.

Simple and rapid HPLC-UV method using an ultrafine particle octadecylsilane for determination of residual fentanyl in applied Durotep MT transdermal matrix patches and its clinical application.

A few complicated and time-consuming methods are available for the determination of residual fentanyl in Durotep MT transdermal patches, however, their application to clinical settings is limited. The aim of this study was to develop a simple and rapid HPLC-UV method using an ultrafine particle octadecylsilane (ODS) for the determination of residual fentanyl in applied Durotep MT transdermal matrix patches. Patch extraction involved sonicating a shredded Durotep MT patch in acetonitrile for 15 min. Fentanyl separation was completed within 2 min using a 2.3-µm particle ODS column (50 × 4.6 mm i.d.) at a flow rate of 1.5 mL/min. No peaks interfering with fentanyl (1.27 min) and papaverine (0.89 min) as an internal standard were observed. The calibration curve for fentanyl was linear over the range of 0.015-9.0 mg as a Durotep MT patch. The intra- and inter-assay precisions and accuracies of each patch were within 5.3% and 103.9-110.5% and within 8.2% and 97.1-104.3%, respectively. The validated method was applied to determine residual fentanyl in Durotep MT patches used in 35 cancer patients. Although the plasma fentanyl concentration was significantly correlated with its measured absorption rate, the measured absorption rate normalized fentanyl concentration showed a large inter-individual variation. The validated simple and rapid HPLC-UV method established in the present study is helpful for evaluating the absorption rate of fentanyl in patients receiving Durotep MT patches.