Developing and Validating a Fast and Accurate Method to Quantify 18 Antidepressants in Oral Fluid Samples Using SPE and LC-MS-MS.

Antidepressant drugs are one of the most widely used medicines for treating major depressive disorders for long time periods. Oral fluid (OF) testing offers an easy and non-invasive sample collection. Detection of antidepressants in OF is important in clinical and forensic settings, such as therapeutic drug monitoring and roadside testing for driving under influence. We developed and validated a comprehensive liquid chromatography-tandem mass spectrometry method for 18 antidepressants (amitriptyline, bupropion, citalopram, clomipramine, cyclobenzaprine, desipramine, desvenlafaxine, doxepin, duloxetine, fluoxetine, imipramine, mirtazapine, nortriptyline, paroxetine, sertraline, trazodone, trimipramine, venlafaxine) in oral fluid collected by Quantisal® oral collection devices. One-half milliliter of Quantisal® OF (125 µL of neat OF) was submitted to solid-phase extraction. The chromatographic separation was performed employing a biphenyl column in gradient mode with a total run time of 5 min. The MS detection was achieved by multiple-reaction monitoring with two transitions per compound. The range for linearity of all analytes was from 10 to 1,000 ng/mL, with a limit of detection of 10 ng/mL. Intra and inter-day accuracy and precision (n = 15) were all within acceptable limits, ±20% error and ±15% relative standard deviation. Analyte recovery at 400 ng/mL concentration (n = 15) ranged from 91 to 129%. Matrix effect ranged from 73.7 to 157%. The internal proficiency test detected all antidepressants with accuracy ranging from 83.1 to 112.1%. The authentic patient sample showed a percentage difference compared to the previously calculated concentration of 86.3-111%. This method provides for the rapid detection of 18 antidepressants and metabolites in OF, which is readily applicable to a routine laboratory.

Delayed hyperthermia from chlorfenapyr overdose.

We describe the hospital course of a 42-year-old patient who presented to the Emergency Department following an ingestion of an unknown quantity of chlorfenapyr, an organochlorine pesticide that acts as a mitochondrial uncoupler (MU). There is limited data on chlorfenapyr toxicity in humans, but reports indicate a 100% mortality rate after a 7-10 day quiescent period.3-6 Our patient was admitted for a 5-day asymptomatic observation period before becoming critically ill. Supportive care, antioxidant therapy, and late hemodialysis (HD) proved futile. The patient expired from complications due to uncontrollable hyperthermia on hospital day 6. This case represents the first reported fatality due to chlorfenapyr in North America, and illustrates: 1) its potency as a human toxin, 2) the futility of extracorporeal decontamination once late toxicity has set in; 3) the potential need for early and aggressive decontamination in the ED; and 4) the need for a better understanding of this unique poison.

Chiral Analysis of Methamphetamine in Oral Fluid Samples: A Method to Distinguish Licit from Illicit Drug Use.

Methamphetamine (MAMP) is a popular illicit drug abused for its central nervous system stimulating effects. MAMP is also used therapeutically in the treatment of overeating disorders, narcolepsy, attention deficit disorder, in over-the-counter (OTC) products to ease nasal congestion. MAMP exists in two enantiomeric forms, dextrorotary (d-MAMP) or levorotary (l-MAMP). The compounds are similar in chemical structure, simply differing in the orientation of functional groups around the asymmetric carbon. In part because of the availability of l-MAMP in OTC nasal inhalers, forensic guidelines require a sample to contain greater than 20% d-MAMP to consider illicit drug use when interpreting results. Standard analytical methods readily detect MAMP in biological specimens but cannot resolve the enantiomeric composition of the sample. Specialized analytical techniques based on chiral separation of the enantiomers are required to differentiate d-MAMP from l-MAMP. Our laboratory sought to develop and validate a method for the analysis of oral fluid specimens for d/l-MAMP using a chiral derivatizing agent and traditional reverse phase liquid chromatography tandem mass spectrometry (LC-MS-MS). MAMP was extracted from dilute oral fluid samples using Strata-XC solid phase extraction (SPE) cartridges and derivatized with Marfey's reagent. Chromatographic separation was achieved using Zorbax Eclipse Plus C18 columns. Linearity, accuracy and precision, recovery, matrix effects and specificity of the method were all within acceptable criteria. Intraday accuracy ranged from 93.3 to 103.4% and precision 0.1 to 1.6%. Interday accuracy ranged from 90.0 to 103.4% and precision 3.8 to 11.6%. Finally, having previously tested positive for MAMP using non-chiral analysis, 256 de-identified authentic oral fluid samples were analyzed using this validated method. 98% of all samples tested positive for d-MAMP at greater than 20%.

A Novel Chronic Opioid Monitoring Tool to Assess Prescription Drug Steady State Levels in Oral Fluid.

OBJECTIVE: Interpretation limitations of urine drug testing and the invasiveness of blood toxicology have motivated the desire for the development of simpler methods to assess biologically active drug levels on an individualized patient basis. Oral fluid is a matrix well-suited for the challenge because collections are based on simple noninvasive procedures and drug concentrations better correlate to blood drug levels as oral fluid is a filtrate of the blood. Well-established pharmacokinetic models were utilized to generate oral fluid steady state concentration ranges to assess the interpretive value of the alternative matrix to monitor steady state plasma oxycodone levels. METHODS: Paired oral fluid and plasma samples were collected from patients chronically prescribed oxycodone and quantitatively analyzed by liquid chromatography tandem mass spectrometry. Steady state plasma concentration ranges were calculated for each donor and converted to an equivalent range in oral fluid. Measured plasma and oral fluid oxycodone concentrations were compared with respective matrix-matched steady state ranges, using each plasma steady state classification as the control. RESULTS: A high degree of correlation was observed between matrices when classifying donors according to expected steady state oxycodone concentration. Agreement between plasma and oral fluid steady state classifications was observed in 75.6% of paired samples. This study supports novel application of basic pharmacokinetic knowledge to the pain management industry, simplifying and improving individualized drug monitoring and risk assessment through the use of oral fluid drug testing. Many benefits of established therapeutic drug monitoring in plasma can be realized in oral fluid for patients chronically prescribed oxycodone at steady state.

A Fast and Comprehensive Analysis of 32 Synthetic Cannabinoids Using Agilent Triple Quadrupole LC-MS-MS.

Synthetic cannabinoids are a group of psychoactive compounds that mimic the effects of Δ9-tetrahydrocannabinol, the primary psychoactive constituent of marijuana (Cannabis sativa L). The Drug Enforcement Administration has classified many of the most common cannabinoids as Schedule 1 controlled substances. As a result, several novel synthetic cannabinoid series have emerged in the illicit drug market, including PINACA, FUBINACA, PB-22, AKB-48 and multiple derivatives of these compounds. Our laboratory developed and validated an analytical method for the analysis 32 synthetic cannabinoid metabolites in urine samples. Included in this method are metabolites that are constituents of the new generation of synthetic cannabinoids. Following enzymatic hydrolysis, target analytes were recovered by liquid-liquid extraction utilizing 1-chlorobutane:isopropyl alcohol (70:30) as the organic ratio. Chromatographic separation and detection was achieved using an Agilent Technologies 1290 liquid chromatograph coupled to a 6460-triple quadrupole mass spectrometer with a Jetstream electrospray source. Linearity for all analytes was established along the range of 0.5-200 ng/mL. Both intraday and interday accuracy and precision data were all within acceptable limits, ±20% error and ±15% relative standard deviation, respectively. Recovery ranged from 48% to 104%. This method has shown to be selective and specific, providing no evidence of interference or carryover concerns. Finally, 11 distinct synthetic cannabinoids were detected in 23 of 25 donor samples analyzed with the method. The data presented here represents a validated liquid chromatography  tandem mass spectrometry method to accurately identify and quantitate synthetic cannabinoid metabolites in urine samples, incorporating new generation derivatives.

Assessment of the use of oral fluid as a matrix for drug monitoring in patients undergoing treatment for opioid addiction.

Drug testing is an important clinical tool that is available to physicians who are assessing the effectiveness of drug treatment as well as patient compliance to the administered program. While urine has traditionally been the matrix of choice for drug monitoring, oral fluid, a filtrate of the blood, has shown great promise as an alternative matrix for such applications. Oral fluid collection can be accomplished without the need for highly trained medical staff through the use of a simple, noninvasive oral fluid collection device, which obtains an adequate sample in only a few minutes. There has been a significant amount of research performed on the use of oral fluid for forensic toxicology application; however, more studies assessing the use of oral fluid drug testing are required to validate its ability to achieve clinical drug monitoring goals. Testing for various drugs in oral fluid may yield a different result when compared to the same drugs in urine, requiring an assessment of the utility of oral fluid for such practices. The purpose of this study was to examine the application of oral fluid drug testing in patients undergoing buprenorphine treatment for opioid dependence. A retrospective analysis of drug testing results obtained from 6,928 patients (4,560 unobserved urine collections and 2,368 observed oral fluid collections) monitored for heroin metabolite, amphetamine, benzodiazepines, buprenorphine, tetrahydrocannabinol, cocaine, codeine, hydrocodone, hydromorphone, methadone, morphine, oxycodone, and oxymorphone was completed. Results of this statistical exercise indicated that patients undergoing observed oral fluid collection tested positive more frequently than those unobserved urine collections for several illicit drugs and prescription medications targeted. Oral fluid was shown to detect illicit drug use as well as noncompliance in this patient population under the studied conditions more often than the urine specimens.

Validation of an EMIT® screening method to detect 6-acetylmorphine in oral fluid.

An automated assay was modified and validated to qualitatively screen for 6-acetylmorphine (6-AM) in oral fluid using the Siemens EMIT II(®) Plus 6-AM urine assay. The validation utilized an oral fluid calibrator at the currently proposed Substance Abuse and Mental Health Services Administration cutoff concentration of 4 ng/mL, as well as quality control material prepared and validated through liquid chromatography-tandem mass spectrometry. All calibrator, quality control and unknown specimens were analyzed based on the dilution and buffering system of the Quantisal(®) oral fluid collection device. Immunoassay parameters such as the pipetted sample and reagent volumes as well as photometric read times were adjusted as part of the assay modification process. Validation experiments included the determination of intra- and inter-day precision and reproducibility, limits of detection (LODs), assay selectivity, stability studies and a specimen agreement study (n = 132). The 6-AM assay performed well in all validation experiments, over multiple days and under various laboratory conditions. The LOD was determined to be 1.844 ng/mL. The assay sensitivity, specificity and overall misclassification rate were found to be 90, 100 and 6%, respectively.

A study of western pharmaceuticals contained within samples of Chinese herbal/patent medicines collected from New York City's Chinatown.

In America, recent growth in the popularity of Chinese herbal/patent medicines (CHM/CPM) has generated concerns as to the safety of these and other herbal remedies. Lack of strict federal regulations has lead to the possibility of improper labeling and even adulteration of these products with western drugs or other chemical contaminants. Our laboratory has conducted an analytical study to determine the presence of undeclared pharmaceuticals and therapeutic substances within CHM/CPM sold in New York City's Chinatown. Ninety representative samples randomly purchased in the form of pills, tablets, creams and teas were screened by appropriate analytical techniques including TLC, GC/MS and HPLC. Five samples contained nine different western pharmaceuticals. Two of these samples contained undeclared or mislabeled substances. One sample contained two pharmaceuticals contraindicated in people for whom the product was intended. Drugs identified include promethazine, chlormethiazole, chlorpheniramine, diclofenac, chlordiazepoxide, hydrochlorothiazide, triamterene, diphenhydramine and sildenafil citrate (Viagra).