Detection of Drugs in Oral Fluid Samples Using a Commercially Available Collection Device: Agreement with Urine Testing and Evaluation of A and B Samples Obtained from Employees at Different Workplace Settings with Uncontrolled Sampling Procedures

The use of oral fluid tests to detect drugs is of growing interest in various areas, including treatment centers, roadside and workplace testing. In this study, we investigated drug detection in oral fluid samples collected using a commercially available device, Oral Eze. Drug detection in oral fluid was compared to paired urine samples, which were simultaneously collected. We also evaluated the collection device by comparing A and B oral fluid samples. Finally, we studied the stability of various drugs in samples stored for at least 1 year. The drug profile was investigated by comparing the drugs detected in oral fluid samples with paired urine samples collected in a treatment center. A total of 113 paired oral fluid and urine samples were investigated for the presence of drugs in the following groups: amphetamines, benzodiazepines, opiates and opioids, cocaine and cannabis. A and B samples were collected from different workplaces through an uncontrolled sampling procedure (n = 76). The stability of drugs in A samples was assessed after storage at -20°C for 1 year. Generally, there was a good correlation between drugs detected in oral fluid samples and urine samples. The heroin metabolite, 6-MAM, was more frequently detected in oral fluid samples than in urine samples, while cannabis was better detected in urine samples. Drugs in oral fluid samples were stable when stored at -20°C for at least 1 year. However, in many positive A and B oral fluid samples, there was significant variation in the concentrations obtained. Hence, the collection device may need to be further standardized and improved.

Evaluation of an immunoassay procedure to measure 6-monoacetylmorphine

Introduction: 6-Monoacetylmorphine (6-MAM) is a specific metabolite of heroin. Thus, the presence of 6-MAM in urine is a definitive indication of heroin intake. The possibility of having an immunoassay procedure to measure 6-MAM would be a diagnosis tool to discriminate, among opiates-positive, those patients who have consumed heroin and those who have not.Methods: EMIT^® II Plus 6-Acetylmorphine Assay was used to measure 6-MAM in urine. The positive opiate screening results were confirmed at the Toxicology laboratory of our hospital by GC-MS.Results: This study includes 63 urine samples from subjects admitted to emergency department with suspicion of opiate consumption. Specificity was evaluated in the two groups of samples studied. In the first group all samples which resulted negative by opiate immunoassay (n = 33) were negative for 6-MAM immunoassay test. Thus, the specificity obtained for 6-MAM immunoassay in this group was 100%. Regarding the second specificity study, performed in positive samples by opiate immunoassay which were negative to 6 MAM by GC-MS, the specificity decreased down to 75%. In the study of sensitivity all samples confirmed as positive to 6-MAM by confirmatory method (GC-MS) resulted positive by the screening method, thus sensitivity obtained was 100%.Discussion: In this study no FN for 6-MAM was observed and therefore the new Emit^® II Plus 6- Acetylmorphine Assay procedure has a high NPV, thus a negative result with 6-MAM immunoassay practically excludes heroine consume. The positive results to 6-MAM by immunoassay should be confirmed by a more analytically specific method, such as GCMS.

Comparison of the Detection Windows of Heroin Metabolites in Human Urine Using Online SPE and LC-MS/MS: Importance of Morphine-3-Glucuronide

Heroin abuse is a serious problem that endangers human health and affects social stability. Though often being used as confirmation of heroin use, 6-monoacetylmorphine (6-MAM) has limitations due to its short detection window. To compare the detection windows of heroin metabolites (morphine (MOR), 6-MAM, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G)) in human urine, an automated online solid phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and fully validated. The limits of detections (LODs) of the four metabolites were in the range of 1.25-5 ng/mL. Intra and inter-day precision for all the metabolites was 0.4-6.7% and 1.8-7.3%, respectively. Accuracy ranged from 92.9 to 101.7%. This method was then applied to the analysis of urine samples of 20 male heroin abusers. M3G was detected 9-11 days after admission to the drug rehabilitation institute in 40% of heroin users while MOR or M6G was not always detected. The detection window of M3G was thus the longest. Furthermore, M3G had a much higher concentration than MOR and M6G. Therefore, M3G could provide diagnostic information with regard to heroin exposure in the combination with other clues (e.g., heroin seizures at the scene).

Detection of heroin intake in patients in substitution treatment using oral fluid as specimen for drug testing

BACKGROUND

Detection of heroin use is among the major tasks for drug testing and can be best performed by using 6-acetylmorphine as the target analyte. This study was performed to document analytical findings in oral fluid after OF heroin intake.

METHODS

The samples were from routine drug testing of patients in substitution treatment. The analytical investigation was made with a forensic accredited liquid chromatography-tandem mass spectrometry method.

RESULTS

Out of 2814 samples, from 1875 patients, sent for routine drug testing, 406 contained one or more opiate in the drug screening when applying a cutoff limit of 1 ng/mL neat OF. Out of these 406, 314 had a measured 6-AM concentration in neat OF ≥ 1 ng/mL. The study demonstrated that 6-AM is a viable parameter in oral fluid drug testing with an about 80% sensitivity compared to using morphine and codeine as biomarkers. An additional value of using 6-AM is the confidence in concluding a heroin intake. The 6-AM concentrations varied between 1 and >1000 ng/mL, with a median value of 18.6 ng/mL. Heroin was measured in 35 samples with a median value of 0.72 ng/mL. The positive rate for opiates in urine and OF drug testing was the same, 13.5%, in similar populations of patients.

CONCLUSIONS

6-AM is a preferred parameter in OF drug testing for monitoring heroin use and makes OF drug testing for detecting heroin use more effective than urine drug testing when using highly sensitive mass spectrometry methods.

A lateral flow strip based on gold nanoparticles to detect 6-monoacetylmorphine in oral fluid

We used lateral flow strips based on gold nanoparticles to detect 6-monoacetylmorphine (6-MAM; heroin's unique metabolite) in oral fluid samples. In this competitive lateral chromatographic immunoassay, the 6-MAM was chemically synthesized and conjugated to bovine serum albumin. The results were qualitatively detected via the colour change of the test line. By using a proper sample pad, a suitable nitrocellulose membrane and a customized sponge device adsorbed the oral fluid directly from the mouth; the total test time was 3 min. The sensitivity of the assay was 4.0 ng ml-1 without any cross-reactivity with 10 normal drugs, which are widely subject to abuse, including morphine and codeine. This test could be easily used on site to detect heroin in oral fluid, and it could be a promising product in the future including for driving under the influence.

Current state of bioanalytical chromatography in clinical analysis

Chromatographic methods have become popular in clinical analysis in both routine and research laboratories.

Effect of UGT2B7 -900G>A (-842G>A; rs7438135) on morphine glucuronidation in preterm newborns: results from a pilot cohort

AIM

Assess association between UGT2B7 polymorphism -900G>A (rs7438135, also known as -842G>A) with morphine kinetics in preterm newborns undergoing mechanical ventilation.

MATERIALS & METHODS

Thirty-four infants were enrolled in a randomized clinical trial and allocated to rapid sequence intubation with remifentanil (1 µg/kg) or morphine (0.3 mg/kg). The latter group was included in our study.

RESULTS

Morphine plasma concentrations at 20 min post intubation were associated with postnatal age (p=0.017) and UGT2B7 -900G>A (p=0.036). UGT2B7 -900A allele carriers (n=13) had lower morphine levels compared with UGT2B7 -900G/G patients (n=2). Morphine-3-glucuronide and morphine-6-glucuronide plasma concentrations were only found to be associated with gestational and postnatal age. However, -900A allele carriers had a higher morphine-3-glucuronide:morphine metabolic ratio compared with patients genotyped as -900G/G (p=0.005), as determined by linear regression.

CONCLUSION

Our small pilot study illustrates that in addition to gestational and postnatal age, the UGT2B7 -900G>A polymorphism significantly alters morphine pharmacokinetics in preterm infants.

Detection of morphine-3-sulfate and morphine-6-sulfate in human urine and plasma, and formation in liver cytosol

Morphine is still the mainstay in treatment of severe pain and is metabolized in the liver mainly by glucuronidation, partly to the pharmacologically active morphine-6-glucuronide (M6G). The sulfation pathway has attracted much less attention but may also form active metabolites. The aim of the present study was to study two sulfate metabolites of morphine in humans. Urine and plasma from newborns, adult heroin addicts, and terminal cancer patients was analyzed for the presence of morphine-3-sulfate (M3S) and morphine-6-sulfate (M6S) by a new liquid chromatography – tandem mass spectrometry (LC-MS/MS) method. In addition, morphine sulfation was studied in vitro in human liver cytosol preparations. M3S was present in urine and plasma from all study groups although at lower concentrations than morphine-3-glucuronide (M3G). The plasma M3S/M3G ratio was 30 times higher in newborns than in adults indicating that the relative sulfation is more important at early stage of life. M6S was measurable in only one plasma sample from a newborn patient, and in one of the urine sample from the drug testing group. The incubation of morphine with liver cytosol extracts resulted in approximately equal rate of formation of both M3S and M6S. In conclusion, sulfation of morphine is catalyzed in human liver but this minor metabolic pathway probably lacks clinical significance. The M6S metabolite is formed at a low rate, making it undetectable in most individuals.

Methods for urine drug testing using one-step dilution and direct injection in combination with LC–MS/MS and LC–HRMS

The advent of LC combined with MS made it possible to design analytical methods for urine drug testing based on the very simple concept of diluting urine with an internal standard as the sole preparation procedure prior to instrumental analysis. The number of publications using this method design increased after the development of high-efficiency LC based on sub-2 μm particles. The success of this method design for drug testing, doping control and toxicological investigations of urine is now well documented and comprise both screening and confirmation methods. The nondiscriminating nature of this method design makes it even more attractive in combination with high-resolution MS for multicomponent target and general unknown analysis applications.