A Study of Opiate, Opiate Metabolites and Antihistamines in Urine after Consumption of Cold Syrups by LC-MS/MS

Studying the origin of opiate and/or opiate metabolites in individual urine specimens after consumption of cold syrups is vital for patients, doctors, and law enforcement. A rapid liquid chromatography-tandem mass spectrometry method using "dilute-and-shoot" analysis without the need for extraction, hydrolysis and/or derivatization has been developed and validated. The approach provides linear ranges of 2.5-1000 ng mL^-1 for 6-acetylmorphine, codeine, chlorpheniramine, and carbinoxamine, 2.5-800 ng mL^-1 for morphine and morphine-3-β-d-glucuronide, and 2.5-600 ng mL^-1 for morphine-6-β-d-glucuronide and codeine-6-β-d-glucuronide, with excellent correlation coefficients (R² > 0.995) and matrix effects (< 5%). Urine samples collected from the ten participants orally administered cold syrups were analyzed. The results concluded that participants consuming codeine-containing cold syrups did not routinely pass urine tests for opiates, and their morphine-codeine concentration ratios (M/C) were not always < 1. In addition, the distribution map of the clinical total concentration of the sum of morphine and codeine against the antihistamines (chlorpheniramine or carbinoxamine) were plotted for discrimination of people who used cold syrups. The 15 real cases have been studied by using M/C rule, cutoff value, and distribution map, further revealing a potential approach to determine opiate metabolite in urine originating from cold syrups.

Positive percentages of urine morphine tests among methadone maintenance treatment clients with HIV/AIDS: a 12-month follow-up study in Guangdong Province, China

OBJECTIVE

We aimed to assess the positive percentages of urine morphine tests and correlates among methadone maintenance treatment (MMT) clients with HIV/AIDS in Guangdong, China.

SETTING

Fourteen MMT clinics located in nine cities of Guangdong were chosen as study sites.

PARTICIPANTS

In this study, we reviewed 293 clients with opioid dependence, who were HIV seropositive, 18 years or older, provided informed consent and had at least 10 records of urine morphine tests during the study period.

PRIMARY AND SECONDARY OUTCOME MEASURES

The positive percentages of urine morphine tests were calculated and underlying predictors were estimated.

RESULTS

The highest positive percentage (95.9%) was observed in the first month. After excluding the highest percentage in the first month, the average positive percentage was 40.9% for month 2 to month 12. Positive percentages of urine morphine tests that were <20%, 20-60% and >80% were 25.4%, 36.1% and 38.5% respectively. Lower percentages of continued heroin use were associated with being young (OR_≤30=0.31, 95% CI 0.12 to 0.78; OR_31-=0.44, 95% CI 0.20 to 1.00), and financial sources depending on family or friends (OR=0.55, 95% CI 0.32 to 0.93). Higher percentages of continued heroin use were associated with being unemployed (OR=1.99, 95% CI 1.13 to 3.49) and poor MMT attendance (OR_<20%=3.60, 95% CI 1.55 to 8.33; OR_20%-=2.80, 95% CI 1.48 to 5.33).

CONCLUSIONS

High positive percentages of urine morphine tests remain prevalent among MMT clients with HIV/AIDS in Guangdong. The present findings have implications for taking effective measures to facilitate attendance in order to decrease heroin use and ultimately improve the effectiveness among these sub-group MMT clients.

Study of the electrical connection mechanism of sheathless interface for capillary electrophoresis-electrospray ionization-mass spectrometry

With the combination of high separation ability of capillary electrophoresis (CE) and strong identification ability of mass spectrometry (MS), CE/MS is becoming a powerful tool for polar and ionic analytes analysis. Different interfaces have been developed to enhance the sensitivity and reliability since the first introduction of CE/MS in 1987. A sheathless porous interface based on a new ions transferring electric connection technique was reported to be with high sensitivity and reliability. In this work, a series of optical and electrochemical experiments were designed to study the electric connection process. The results indicated that closing CE electrical circuit and applying MS spray voltage were achieved by the small ions transferring through the interface porous wall. The new electric connection method significantly enhanced the sensitivity, resolution and stability of the CE/MS analysis. The interface was applied in CE/MS detection of morphine and 6-monoacetylmorphine in urine sample and showed an equal sensitivity to LC/MS. With the significant improvement of sensitivity and stability, the CE/MS with the new interface showed strong potential for the determination of low abundance analytes.

[Simultaneous determination of opioid compounds in human urine by UPLC-MS/MS]

OBJECTIVE

To propose a method for simultaneous determination of codeine(COD), 6-monoacetyl-morphine (6-MAM), morphine (MOR), morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) in human urine by ultra performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS).

METHODS

After precipitation of protein by acetonitrile, the urine samples, with added the morphine-d3 (MOR-d3) and morphine-3-Glucuronide-d3 (M3G-d3) as internal standards, were pre-treated by Sirocco protein precipitation plate, and then analyzed by UPLC-MS/MS.

RESULTS

The limit of detection was 0.2 ng/mL for both COD and MAM, the limit of quantitation was 0.5 ng/mL for both COD and MAM. The limit of detection was 0.5 ng/mL for MOR, M3G and M6G, the limit of quantitation was 1 ng/mL for them. The linear correlation coefficients were not less than 0.9997, both the inter-day and intra-day precisions were less than 10%, the recoveries were in the range of 70.0% to 98.3%, the matrix effects were about 50.5% to 99.0%.

CONCLUSION

This proposed method is simple, rapid and accurate, it could be applied in forensic toxicological analysis.

Tunable detection sensitivity of opiates in urine via a label-free porous silicon competitive inhibition immunosensor

Currently, there is need for laboratory-based high-throughput and reliable point-of-care drug screening methodologies. We demonstrate here a chip-based label-free porous silicon (PSi) photonic sensor for detecting opiates in urine. This technique provides a cost-effective alternative to conventional labeled drug screening immunoassays with potential for translation to multiplexed analysis. Important effects of surface chemistry and competitive binding assay protocol on the sensitivity of opiate detection are revealed. Capability to tune sensitivity and detection range over approximately 3 orders of magnitude (18.0 nM to 10.8 muM) was achieved by varying the applied urine specimen volume (100-5 muL), which results in systematic shifts in the competitive binding response curve. A detection range (0.36-4.02 muM) of morphine in urine (15 muL) was designed to span the current positive cutoff value (1.05 muM morphine) in medical opiate urine screening. Desirable high cross-reactivity to oxycodone, in addition to other common opiates, morphine, morphine-3-glucuronide, 6-acetyl morphine, demonstrates an advantage over current commercial screening assays, while low interference with cocaine metabolite was maintained. This study uniquely displays PSi sensor technology as an inexpensive, rapid, and reliable drug screening technology. Furthermore, the versatile surface chemistry developed can be implemented on a range of solid-supported sensors to conduct competitive inhibition assays.

Quantitation of opioids in blood and urine using gas chromatography-mass spectrometry (GC-MS)

The opioid and 6-acetylmorphine assays utilize gas chromatography-mass spectrometry (GC-MS) for the analysis of morphine, codeine, hydromorphone, hydrocodone, and 6-acetylmorphine in blood and urine. The specimens are fortified with deuterated internal standard and a five-point calibration curve is constructed. Specimens are extracted by mixed-mode solid phase extraction. The morphine, codeine, hydromorphone, hydrocodone, and 6-acetylmorphine extracts are derivatized with N-methyl-bis(trifluoroacetamide) (MBTFA) producing trifluoroacetyl derivatives. The final extracts are then analyzed using selected ion monitoring GC-MS.

GC-MS analysis of multiply derivatized opioids in urine

Opiates such as hydrocodone, hydromorphone, oxycodone, noroxycodone, and oxymorphone reportedly may interfere with the analysis of morphine and codeine. The analysis of these compounds themselves also is an important issue. Thus, double derivatization approaches utilizing methoxyamine and hydroxylamine to first form oxime products with keto-opiates, followed by the derivatization with trimethylsilyl (TMS) or propionyl groups, have been developed for the simultaneous analysis of these compounds. However, these studies have not included all compounds of interest and resulted in inadequate chromatographic resolution or significant intensity cross-contribution between the ions designating the analyte and its deuterated internal standard for certain compounds. By exploring three-step derivatization approaches with the combination of various derivatization groups and orders, this study concluded that application of methoxyimino/propionyl/TMS groups, in the order listed, facilitated the simultaneous analysis of eight opiates (morphine, 6-acetylmorphine, hydromorphone, oxymorphone, codeine, hydrocodone, oxycodone and noroxycodone) in urine samples, achieving satisfactory limits of quantitation and detection. In addition, the adapted approach resulted in two usable products for morphine and codeine providing alternatives, should interferences render any of these products non-usable.

Long-term stability of various drugs and metabolites in urine, and preventive measures against their decomposition with special attention to filtration sterilization

The long-term stability of drugs and metabolites of forensic interest in urine, and preventive measures against their decomposition have been investigated, with special attention to filtration sterilization. An aseptic urine collection kit, which was recently developed based on filtration sterilization, was utilized for the aseptic collection and storage of urine samples. For evaluating preservation measures, methamphetamine (MA), amphetamine (AP), nitrazepam (NZ), estazolam (EZ), 7-aminoflunitrazepam (7AF), cocaine (COC), and 6-acetylmorphine (6AM) were spiked into urine at 500 ng/mL each, and were monitored for 6 months at 25, 4, and -20 degrees C, after the addition of NaN(3) and/or filtration sterilization using the aseptic collection kit. In severely contaminated urine with bacteria, there were significant losses of 7AF and NZ, and slight decomposition of MA and AP at 25 degrees C. However, such degradation was successfully suppressed by the use of the kit, though the use of the kit and NaN(3) were preferred for 7AF. The kit was also effective in preventing the hydrolyses of COC and 6AM, while it was suggested that the common preservative NaN(3) can accelerate the hydrolysis of such ester-type drugs and metabolites.

Electrospray LC-MS Method with Solid-Phase Extraction for Accurate Determination of Morphine-, Codeine-, and Ethylmorphine-Glucuronides and 6-Acetylmorphine in Urine

A method for the identification and quantification of morphine-3-glucuronide, codeine-6-glucuronide, ethylmorphine-6-glucuronide, and 6-acetylmorphine in human urine based on solid-phase extraction (SPE) and electrospray ionization liquid chromatography-mass spectrometry (LC-MS) was validated for use as a confirmation procedure in combination with immunochemical screening for opiates. Three deuterium-labelled analogues were used as internal standards: morphine-3-glucuronide-d3, codeine-d3, and 6-acetylmorphine-d3. Fifty-microliter aliquots of urine were prepared by SPE using 30-mg Oasis HLB cartridges. The chromatographic system consisted of a 2.0 x 100-mm C18 column and the gradient elution buffers used acetonitrile and 25 mmol/L formic acid. The protonated molecular ions were monitored in the selected ion monitoring mode together with one qualifier ion for each analyte. The interassay variability was less than 10% at the reporting limit 30 ng/mL for 6-acetylmorphine and 300 ng/mL for the other analytes. The method was validated by comparison with a reference gas chromatographic (GC)-MS method using authentic urine samples. The two methods agreed completely regarding identified analytes, and for the quantitative results there were slightly lower levels when measuring glucuronides directly as compared to total determination after hydrolysis by GC-MS. This result was to be expected because the free compounds are not measured with the LC-MS method. This study concludes that the presented LC-MS method is robust and reliable, and suitable for use as a confirmation method in clinical urine drug testing for opiates.

Influence of Phenobarbital on Morphine Metabolism and Disposition:LC-MS/MS Determination of Morphine (M) and Morphine-3-Glucuronide (M3G) in Wistar-Kyoto Rat Serum, Bile, and Urine

A simple LC-MS/MS method has been developed and validated for the simultaneous determination of morphine (M) and morphine-3-glucuronide (M3G) in rat serum, bile, and urine. Deuterated D3-M and D3-M3G were used as internal standards (IS) for M and M3G, respectively. Serum samples were processed by acetonitrile precipitation. Bile samples were prepared by solid-phase extraction (SPE) using Oasis MCX cartridges. Urine samples were directly analyzed after dilution with mobile phase. Chromatography was performed using a Luna C18 column (5 microm, 150x2.1 mm I.D.). The mobile phase consisted of acetonitrile (ACN) and 7.5 mM ammonium formate (pH 9.3) delivered from separate pumps with a simple gradient. The method was validated to quantify M in the range of 1-1000 ng/ml in bile and serum, and 0.025-25 microg/ml in urine. M3G was quantified in the range of 1-1000 ng/ml in serum, 0.1-100 microg/ml in bile, and 0.05-25 microg/ml in urine. The method was applied to study the pharmacokinetics and disposition of M and M3G in Wistar-Kyoto (WKY) rats, and the effect of phenobarbital (PB) on M and M3G disposition. M is metabolized to M3G at a lower rate in male than female rats leading to higher M levels and lower M3G levels in serum, urine, and bile of male than female rats. PB administration induces M glucuronidation to M3G in male, but not female WKY rats, and abolishes the gender differences in M and M3G pharmacokinetics.

The Significance of Putative Urinary Markers of Illicit Heroin Use After Consumption of Poppy Seed Products

After consumption of poppy seeds various substances were detected in urine or blood samples using an immunoassay and a sophisticated liquid chromatographic-tandem mass spectrometric procedure. These compounds are widely considered to be putative markers of heroin (HER) abuse whereas acetylcodeine was regarded as a marker for illicit preparations ("street HER"). Besides positive urinary opiate immunoassay results during a 48 hours monitoring period, peak concentrations of morphine (MOR), codeine and their glucuronides appeared 4 to 8 hours after ingestion of poppy seeds, and concentrations of total MOR higher than 10 microg/mL were observed. Also, in serum samples taken up to 6 hours after consumption, MOR glucuronides were found. Free MOR was only detected in traces (1 to 3 ng/mL) within 2 hours of consumption. In addition, 3 of 6 onsite opiate sweat tests revealed positive results 6.5 hours after ingestion. Furthermore, it was demonstrated that neither noscapine (NOS) nor papaverine (PAP) was detectable in urine or blood samples after the consumption of poppy seeds containing up to 94 microg NOS and up to 3.3 mug PAP. NOS and PAP were rapidly metabolized, whereas desmethylpapaverine and, especially, its glucuronide were found in urine samples of poppy seed consumers even 48 hours after consumption. According to these results PAP metabolites should not be regarded as markers of illicit HER abuse. In conclusion, only acetylcodeine can be regarded as a specific marker but has the problem of a short half-life. Therefore, we suggest that NOS and PAP, but not their metabolites, might be used cautiously as additional markers of illicit HER abuse as they have not been detected after oral intake of poppy seeds in normal doses. But it must be kept in mind that in some cases poppy seeds with an unusually high content of these alkaloids could be available, and that these substances are also agents in some pharmaceuticals.

Comparison of the Various Opiate Alkaloid Contaminants and Their Metabolites Found in Illicit Heroin with 6-Monoacetyl Morphine as Indicators of Heroin Ingestion

In this study the use of the various opiate alkaloid contaminants as potential markers for illicit heroin ingestion were investigated. Urine samples (n = 227) taken from prisoners for routine drug screen, which were positive for opiates by immunoassay screening, were analyzed for contaminants in illicit heroin. A previously described method was used for the analysis; urines were extracted using mixed-mode solid-phase extraction; the extracts were derivatized using N-methyl-bistrifluoroacetamide and N-methyl-N-trimethylsilyltrifluoroactamide/trimethylchlorosilane. The derivatized extracts were subjected to electron impact gas chromatography-mass spectrometry. The extracts were injected in full scan mode followed by selected ion monitoring mode for target opiate alkaloids found as contaminants in illicit heroin. The opiate alkaloids and their metabolites specifically targeted included meconine, desmethylmeconine, hydrocotarnine, acetylcodeine, codeine, morphine, 6-monacetylmorphine (6-mam), papaverine, hydroxypapaverine, and dihydroxypapaverine. Of the 227 samples positive for opiates by immunoassay, using a cut-off of 300 ng/mL, 199 were confirmed positive for morphine and using a cut-off of 10 ng/mL, 28 were confirmed positive for 6-mam. Using the screening method described in the study, the following numbers of positives were found: 199 for morphine, 103 for codeine, 5 for meconine, 46 for desmethylmeconine, 18 for 6-mam, 136 for hydroxypapaverine, and 139 for dihydroxypapaverine. Acetylcodeine, hydrocotarnine, and papaverine were not detected in any of the samples. The results of this study show that analysis for papaverine metabolites is more sensitive than 6-mam as a way of demonstrating illicit heroin use.

Paradoxical Results in Urine Drug Testing for 6-Acetylmorphine and Total Opiates: Implications for Best Analytical Strategy

A major task in urine drug testing is to detect heroin intake. The most common way of doing this is by using morphine as the analytical target in opiate immunoassay screening. However, this strategy sometimes leads to false-positive results because morphine is not a metabolite unique to heroin. The objective of this study was to evaluate the usefulness of the unique heroin metabolite 6-acetylmorphine (6-AM) as the primary analytical target in combination with morphine in the screening assay. A total number of 3521 randomly collected urine samples from 707 patients undergoing heroin substitution treatment were investigated for 6-AM and opiates by CEDIA (cloned enzyme donor immunoassay) and for opiates by DRI immunoassays and by gas chromatography-mass spectrometry (free 6-AM, free morphine, total morphine, and total codeine). The rate of positive outcome in the screening for 6-AM was 9.1% (cutoff 10 microg/L), and for opiates, it was 22.6% (cutoff 300 microg/L), which is in accordance with a known shorter detection time for 6-AM following heroin intake. However, by comparing 6-AM and opiate screening results at different cutoff levels, it was observed that 7-8% of the samples and 12.5% of the patients with detectable 6-AM had an unexpected low content of free and total morphine in the urine. This study confirms earlier observations that certain individuals may escape detection in urine drug testing when morphine is being utilized for the detection of heroin intake. The underlying mechanism for this may be a metabolic defect and/or interaction. It is concluded that 6-AM is a valuable target analyte in the screening of drugs of abuse in urine and may be used in combination with opiate screening in clinical testing.

Fatal heroin intoxication in body packers in northern Thailand during the last decade: two case reports

A body packer is an important means of drug trafficking. While drug packets are inside the body, they can leak or rupture causing acute substance toxicity. Most of the reports of body packer syndrome have come from Europe and North America, which are destination targets. In the present study, the authors reported two cases of fatal heroin body packers from the northern part of Thailand. Both cases were foreign tourists who came to Chiang Mai and stayed in a hotel or a guesthouse room in which the deaths occurred. The autopsy findings revealed rupturing of heroin packages in the stomach. The packaging used in both cases was not sophisticated. The powder was packed inside condoms without extra covering, as observed in some other professional packers. The amount of heroin transported was about 30-50 gm. The purity of heroin in this powder was about 50-90%. Their destinations were their home countries and not directly to Europe or North America. Deaths occurred just prior to their return. The cause of death was a heroin overdose. A significant level of heroin metabolites, 6-MAM and morphine were detected in the blood and urine.

Surface-activated chemical ionization ion trap mass spectrometry in the analysis of drugs in dilute urine samples. Part II: analysis of morphine and other street drugs

The new ionization method, called surface-activated chemical ionization (SACI), was employed for the analysis of fives drugs (morphine, codeine, 6-monoacetylmorphine (6-MAM), benzoylecgonine and cocaine) by ion trap mass spectrometry. The results so obtained have been compared with those achieved by using atmospheric pressure chemical ionization (APCI), no-discharge-APCI and electrospray ionization (ESI) clearly showing that SACI is the most sensible one mainly due to the high ionization efficiency and the lower chemical noise. The performance of SACI in terms of sensitivity and linearity was compared with the sensitivity and linearity obtained using APCI, no-discharge-APCI and ESI, showing that the new SACI approach gives rise to the best results. Then, SACI was used to analyze morphine, codeine, 6-MAM, benzoylecgonine and cocaine in urine samples. After the optimization of the instrumental parameters for a mixture of the standard compounds, eight urine samples were analyzed. They were strongly diluted (1 : 20 and 1 : 100) in order to prevent the chromatographic column damage due to the matrix composition. Furthermore, the diluted urine samples were directly analyzed, without pretreatment, through LC-MS and LC-MS/MS, and the obtained results are reported.

The reliability of immunoassay for determining the presence of opiates in the forensic setting

Urine immunoassays are commonly used as a rapid screen for drugs of abuse in emergency room, hospital, clinic, and forensic settings. The authors were concerned whether or not a negative screen of the urine for opiates was of significance and indicative that analysis of blood for opiates was not necessary. Specifically, we wished to determine whether a negative test for opiates by immunoassay absolutely rules out an acute overdose, and if not, what percentage of cases with negative results have opiates in the blood. A retrospective analysis was performed using the toxicology results for cases ruled an acute narcotic overdose at the Bexar County Medical Examiner's Office between 1998 and 2003. One hundred eighty-three cases met the criteria for the study. A false-negative rate of approximately 15% was found using an immunoassay as compared with blood analysis for narcotics. The authors feel that while this rate may be acceptable in a clinical setting, it is unacceptable in a forensic setting.

LC-ESI-MS/MS analysis for the quantification of morphine, codeine, morphine-3-beta-D-glucuronide, morphine-6-beta-D-glucuronide, and codeine-6-beta-D-glucuronide in human urine

A liquid chromatographic-electrospray ionization-tandem mass spectrometric method for the quantification of the opiates morphine, codeine, and their metabolites morphine-3-beta-D-glucuronide (M-3-G), morphine-6-beta-D-glucuronide (M-6-G) and codeine-6-beta-D-glucuronide (C-6-G) in human urine has been developed and validated. Identification and quantification were based on the following transitions: 286 to 201 and 229 for morphine, 300 to 215 and 243 for codeine, 462 to 286 [corrected] for M-3-G, 462 to 286 for M-6-G, and 476 to 300 for C-6-G. Calibration by linear regression analysis utilized deuterated internal standards and a weighting factor of 1/X. The method was accurate and precise across a linear dynamic range of 25.0 to 4000.0 ng/ml. Pretreatment of urine specimens using solid phase extraction was sufficient to limit matrix suppression to less than 40% for all five analytes. The method proved to be suitable for the quantification of morphine, codeine, and their metabolites in urine specimens collected from opioid-dependent participants enrolled in a methadone maintenance program.

GC-MS Quantitation of Codeine, Morphine, 6-Acetylmorphine, Hydrocodone, Hydromorphone, Oxycodone, and Oxymorphone in Blood*

A method is described for the simultaneous analysis of seven opiates, codeine, morphine, 6-acetylmorphine, hydrocodone, hydromorphone, oxycodone, and oxymorphone, in blood samples by gas chromatography-mass spectrometry (GC-MS). One milliliter of blood is combined with an internal standard mixture containing 200 ng of each of the seven deuterated opiates. Two milliliters of acetonitrile is added to precipitate the proteins and cellular material. After centrifugation, the clear supernatant is removed, and the acetonitrile is evaporated. The remaining aqueous portion is adjusted to pH 9 with sodium bicarbonate buffer, and the drugs are extracted into chloroform/ trifluoroethanol (10:1). The organic extractant is transferred and dried under nitrogen. The residue is reconstituted in dilute hydrochloric acid and washed consecutively with hexane and chloroform. The purified aqueous portion is adjusted to pH 9 with bicarbonate buffer, and the drugs are again extracted into chloroform/trifluoroethanol (10:1). The organic portion is removed from the aqueous fraction and dried under nitrogen. The residue is consecutively derivatized with methoxyamine and propionic anhydride using pyridine as a catalyst. The ketone groups on hydrocodone, hydromorphone, oxycodone, and oxymorphone are converted to methoximes. Hydroxyl groups present at the O(3) and O(6) positions of codeine, morphine, 6-acetylmorphine, hydromorphone, and oxymorphone are converted to their respective propionyl esters. After a post-derivatization purification step, the extracts are analyzed by full scan GC-MS using electron impact ionization. The method is linear to at least 2000 ng/mL. Day-to-day precision (N = 15) at 500 ng/mL and 75 ng/mL were less than 10% for all seven targeted opiates. Extraction efficiencies at these two concentrations ranged from 50% to 68%. For each opiate, the limit of quantitation was 10 ng/mL, and the limit of detection was 2 ng/mL.

Evaluation of the Cedia(R) Heroin Metabolite (6-AM) Immunoassay with Urine Specimens from a Criminal Justice Drug-Testing Program

The ability to differentiate illicit from legitimate drug use in a drug-testing program would decrease costs by reducing the number of screening specimens requiring confirmation and also reduce the stigma attached to positive preliminary test results. Because many screening tests for drug detection use immunoassays, increasing the specificity of these tests has been a goal of manufacturers. In this study we evaluated the utility of one such assay, the Cedia heroin metabolite (6-acetylmorphine, 6-AM) assay to reliably detect heroin use. Specimens (N = 525) from a criminal justice drug-testing program were screened with this assay (cutoff concentration = 10 ng/mL 6-AM) and any positive samples were confirmed by gas chromatographic-mass spectrometric analysis (lower reporting limit for 6-AM = 5 ng/mL). The confirmation rate for the enzyme immunoassay (EIA) was 98% (517/525). Specimens contained 6-AM at concentrations ranging from 5 to 16,923 ng/mL (mean = 1251; median = 317). All confirmed specimens also contained morphine (range: 8-222,427 ng/mL; mean = 11,203 ; median = 4134). When challenged with standard drug solutions, the EIA correctly identified drug-free urine and produced positive results (lowest concentration, in ng/mL, that produced a positive result) with morphine at 10,000; oxycodone at 61,000; codeine at 60,000; hydromorphone at 10,000; hydrocodone at 60,000, 6-AM at 10, and pentazocine at 35,000 ng/mL. The Cedia heroin metabolite (6-AM) assay produced a high confirmation rate when challenged with urine specimens and therefore should be a useful tool in forensic toxicology. Potential users should be aware that high concentrations of other opioids (e.g., morphine, oxycodone) and structurally related compounds (e.g., pentazocine) may produce positive results.

Comparison of the Microgenics CEDIA(R) Heroin Metabolite (6-AM) and the Roche Abuscreen(R) ONLINE Opiate Immunoassays for the Detection of Heroin Use in Forensic Urine Samples

Current Department of Defense (DoD) and Department of Health and Human Services (HHS) procedures for the detection of heroin abuse by testing urine utilize an initial opiate (codeine/morphine) immunoassay (IA) screen followed by gas chromatography-mass spectrometry (GC-MS) confirmation of 6-acetylmorphine (6-AM), if the morphine concentration is above established cutoff. An alternative to the current opiates screen for heroin abuse is the direct IA for the metabolite of heroin, 6-acetylmorphine. In this regard, the performance of the Microgenics CEDIA heroin metabolite (6-AM) screening reagent was assessed. This evaluation was conducted on the P module of a Hitachi Modular automated IA analyzer calibrated using 6-AM at 10 ng/mL. Reproducibility, linearity, accuracy, sensitivity, and interferences associated with use of the 6-AM IA reagent were evaluated. The IA reagent precision (percent coefficient of variation (%CV)) around each of seven standards was less than 0.63%, with a linearity (r(2)) value of 0.9951. A total of 37,713 active duty service members' urine samples were analyzed simultaneously using the CEDIA heroin metabolite (6-AM) reagent and the Roche Abuscreen ONLINE opiate reagent to evaluate both the prevalence rate of 6-AM in the demographic group and the sensitivity and specificity of the reagents for the detection of heroin use. Of the 37,713 samples tested using the CEDIA heroin metabolite (6-AM) reagent, three samples screened positive at the DoD and HHS cutoff of 10 ng/mL. One of the three samples confirmed positive for 6-AM by GC-MS above the cutoff of 10 ng/mL, the two remaining samples confirmed negative for 6-AM at a GC-MS limit of detection (LOD) of 2.1 ng/mL. In contrast, the Roche Abuscreen ONLINE opiate IA produced 74 opiate-positive results for codeine/morphine, with 6 of the 74 specimens confirming positive for morphine above the DoD cutoff concentration of 4000 ng/mL (8% DoD morphine confirmation rate), only one of the 74 opiate-positive screen specimens confirmed positive for 6-AM above the 10 ng/mL GC-MS cutoff concentration. As a further check of the sensitivity and specificity of the Microgenics 6-AM IA reagent, human urine samples (n = 87) known to contain 6-AM by GC-MS, were re-analyzed using both IA reagents. All 87 of the samples screened positive using the CEDIA heroin metabolite (6-AM) assay. However, using the Roche ONLINE opiate reagent, 12 of the known 6-AM positives screened negative at the DoD and HHS screening cutoff of 2000 ng/mL (morphine). Of the remaining 75 samples that screened positive by the ONLINE opiate reagent, five of the samples did not contain morphine above the DoD GC-MS cutoff concentration of 4000 ng/mL and would not have required 6-AM analysis. However, under the HHS GC-MS morphine cutoff concentration of 2000 ng/mL all 75 samples would have required 6-AM analysis. Furthermore, using the current DoD opiate screen, 17 out of 87 samples known to contain 6-AM would have gone undetected (19.5% false-negative rate); additionally, even under the more stringent HHS opiate screening standards 12 out of the 87 samples known to contain 6-AM would also have gone undetected (13.8% false-negative rate). The Microgenics CEDIA heroin metabolite (6-AM) reagent assay appears well adapted for the rapid and specific detection of heroin abuse as an alternative for, or an adjunct test to, the current opiates (codeine/morphine) IA screening procedure.

Determination of multiple drugs of abuse in human urine using capillary electrophoresis with fluorescence detection

Methods for separation and determination of multiple drugs of abuse in biological fluids using capillary electrophoresis (CE) with native fluorescence and laser-induced fluorescence (LIF) detection are described herein. Using native fluorescence, normorphine, morphine, 6-acetyl morphine (6-AM), and codeine were analyzed by CE without any derivatization procedure and detected at an excitation wavelength of 245 nm with a cut-off emission filter of 320 nm, providing a rapid and simple analysis. The detection limits were in the range of 200 ng/mL. For a highly sensitive analysis, LIF detection was also examined using a two-step precolumn derivatization procedure. In this case, drugs extracted from human urine were first subjected to an N-demethylation reaction involving the use of 1-chloroethyl chloroformate (ACE-Cl) and then derivatized using fluorescein isothiocyanate isomer I (FITC) and analyzed by CE coupled to a LIF detector. Variables affecting this derivatization: yield of demethylation reaction, FITC concentration, reaction time and temperature, were studied. The estimated instrumental detection limits of the FITC derivatives were in the range of 50-100 pg/mL, using LIF detection with excitation and emission wavelengths of 488 nm and 520 nm, respectively. The linearity, reproducibility and reliability of the methods were evaluated. In addition, a comparison of the characteristics for both native fluorescence and LIF detections was also discussed.

High levels of morphine-6-glucuronide in street heroin addicts

RATIONALE

In the body, heroin is rapidly transformed to 6-acetylmorphine (6-AM) and then to morphine, that in turn is mainly metabolized to morphine-3-glucuronide (M3G) and, at lesser extent, to morphine-6-glucuronide (M6G). Unlike M3G, M6G is a potent opioid agonist. Intravenous heroin abusers (IHU) are exposed to a wide array of drugs and contaminants that might affect glucuronidation.

OBJECTIVES

We assessed plasma and urine concentrations of M3G and M6G in four groups of subjects: the first two included long-term IHU either exposed to street heroin ( n=8) or receiving a single IV injection of morphine ( n=4), while the other two groups included non-IHU patients receiving acute IV ( n=8) or chronic oral ( n=6) administrations of morphine.

METHODS

After solid phase extraction plasma and urine concentrations of morphine metabolites were determined by HPLC analyses.

RESULTS

M3G accounted for the greater part of morphine glucuronides detected in body fluids of non-IHU patients treated with morphine. This pattern of metabolism remained stable across 15 days of oral administration of incremental doses of morphine. In contrast, the two groups of IHU (street heroin taking or morphine-treated subjects) showed a reduction of blood and urine M3G concentrations in favor of M6G. Consequently, M6G/M3G ratio was significantly higher in the two IHU groups in comparison with the non-IHU groups.

CONCLUSIONS

Chronic exposure to street heroin causes a relative increase in concentrations of the active metabolite, M6G. Since the pattern of M6G action seems closer to heroin than to morphine, the increased synthesis of M6G observed in IHU may prolong the narrow window of heroin effects.

Interpretation of the Presence of 6-Monoacetylmorphine in the Absence of Morphine-3-glucuronide in Urine Samples

The presence of morphine in a urinary sample may be caused not only by intake of heroin but also by intake of poppy-seed-containing food shortly before urine sampling or intake of drugs containing morphine, ethyl morphine, or codeine. To facilitate the interpretation, the heroin-specific metabolite 6-monoacetylmorphine (6-MAM) can be analyzed along with morphine-3-glucuronide (M3G) in an LC-MS verification analysis. In sporadic samples positive in the immunologic opiate screening test, 6-MAM, but not M3G, was found. To systematically analyze the finding all specimens with positive 6-MAM and/or M3G found during a 1-year period were investigated (n = 1923). Of these, 423 were positive for 6-MAM. In 32 (7.6%) of the samples 6-MAM was detected while the M3G concentrations were below cutoff (300 ng/mL) and in some cases even below the limit of detection (15 ng/mL). The 32 samples with this excretion pattern came from 13 different individuals, all but one with previously known heroin abuse. Eleven urine samples, nine containing M3G and 6-MAM and two with only 6-MAM, were also analyzed for the presence of heroin. In six samples, including the two with only 6-MAM, heroin was detected. There are several plausible explanations for these findings. The intake may have taken place shortly before urine sampling. High concentrations of heroin and 6-MAM may inhibit UGT 2B7, the enzyme responsible for glucuronidation of morphine. The hydrolyzation of 6-MAM to morphine may be disturbed by either internal or external causes. To elucidate this, further studies are required. Nevertheless, our finding demonstrates that routine measurement of 6-MAM when verifying opioid-positive immunologic screening results facilitates interpretation of low concentrations of M3G in urine specimens.

Production of a recombinant anti-morphine-3-glucuronide single-chain variable fragment (scFv) antibody for the development of a "real-time" biosensor-based immunoassay

A recombinant single-chain variable fragment (scFv) antibody to morphine-3-glucuronide (M3G) was produced using genetic material obtained from the spleen cells of mice immunised with a morphine-3-glucuronide-bovine serum albumin (M3G-BSA) conjugate. Immunoglobulin light (V(L)) and heavy (V(H)) chain genes were amplified and cloned into pAK vectors for generation of recombinant antibody fragments in Escherichia coli. A competition ELISA assay was developed in PBS to characterise the ability of the antibody fragments to recognise free drug and the detection limits were found to be as low as 3 ng ml(-1). Surface plasmon resonance-based inhibition immunoassays were developed. The recombinant antibody was pre-incubated with various concentrations of free drug followed by injection over a morphine-3-glucuronide-thyroglobulin (M3G-THY) immobilised surface. The response of antibody binding to the surface of the chip was inversely proportional to the amount of free drug in solution. Regeneration conditions for antibody binding to the surface were optimised resulting in a binding-regeneration capacity of at least 30 cycles. The inhibition assay for M3G was tested with assay ranges between 3 and 195 ng ml(-1) and 3 and 97 ng ml(-1) in PBS and urine, respectively.

Immunoassay for the determination of morphine-3-glucuronide using a surface plasmon resonance-based biosensor

Polyclonal antibodies were produced for the development of competitive ELISA's and surface plasmon resonance (SPR)-based BIAcore inhibition assays for the detection of morphine-3-glucuronide (M3G, the main metabolite of heroin and morphine). A conjugate consisting of M3G and ovalbumin was produced and used for the generation of antibodies, for the coating of immunoplates and for immobilisation onto BIAcore chips. Competition ELISA's were developed in PBS and urine to characterise the antibodies ability to recognise free M3G. SPR-based inhibition immunoassays on BIAcore were developed. The regeneration of the surface of a chip immobilised with conjugate following antibody binding, essential for the development of inhibition assays was investigated. Regeneration of the conjugate-coated surface was optimised for both polyclonal antibodies resulting in binding-regeneration capacities of approximately 60 cycles for one antibody and 50 cycles for the second antibody. The inhibition assays developed in urine had ranges of detection of 762-24,400 (antibody 1) and 976-62,500 pg ml(-1) (antibody 2). The inter-day coefficients of variation for the assays ranged from 1.48 to 11.24%.

A rapid GC-MS method for the determination of dihydrocodeine, codeine, norcodeine, morphine, normorphine and 6-MAM in urine

The presence of the heroin metabolite 6-monoacetylmorphine (6-MAM) in urine is used to definitively identify recent heroin abuse. A rapid and sensitive GC-MS method for the simultaneous analysis of codeine, norcodeine, morphine, normorphine and 6-MAM in urine was developed and successfully applied to the analysis of 321 'heroin-positive' urine specimens from individual subjects (identified by the presence of 6-MAM), to provide quantitative urinary opiate excretion data for heroin abusers. The cohort analysed was composed of 238 males (age range 16-53 years) and 83 females (age range 16-50 years). The concentrations of free 6-MAM, morphine and codeine determined in these 321 specimens ranged between 103-246,312, 129-193,600 and 103-519,000 microg/l, respectively. Free norcodeine and normorphine concentrations were found to range between 143-50,200 and 205-149,700 microg/l, respectively. A statistically significant relationship was determined between the subject age and the 6-MAM concentration, possibly indicating opiate tolerance in these individuals.

Application of the CEDIA 6-MAM assay to routine drugs-of-abuse screening

A total of 1010 urine specimens obtained from General Practitioners, drug dependency units, and hospitals throughout the West Midlands were screened using the Microgenics CEDIA 6-monoacetylmorphine (6-MAM) assay as a means of establishing its effectiveness as a screening technique to monitor heroin abuse. A total of 282 specimens screened positive for 6-MAM using the CEDIA 6-MAM assay. However, the presence of 6-MAM could not be confirmed by gas chromatography-mass spectrometry in 21 (7%) of the CEDIA-positive specimens. Morphine was identified in all of these specimens at free concentrations ranging between 410 microg/L to 2010 microg/L. The data presented from this preliminary investigation suggests that either there are substances present within the urine specimens, as yet undetermined, which are interfering with the assay or that there may be a greater degree of cross reactivity to other opiates than previously published. 6-MAM assays may be potentially useful rapid screening techniques for high-throughput drugs-of-abuse screening laboratories performing employment and pre-employment screening. However, all positive results will still need to be confirmed by a more sensitive and specific technique.

[Column-switching high-performance liquid chromatographic method for the determination of morphine and O6-monoacetylmorphine in urine]

OBJECTIVE

To develop a column-switching high-performance liquid chromatographic method for the determination of morphine and O6-monoacetylmorphine in urine.

METHODS

Urine samples (1.0 ml) were spiked with 1.0 ml borate buffer, after centrifugation, 1.0 ml of supernate were injected directly into an extraction column (YWG C18 33 mm x 5.0 mm, 10 microns). After a washing step with the extraction mobile phase, the retained morphine and O6-monoacetylmorphine were flushed into the analytical column (Lichrospher 100 CN 125 mm x 4.0 mm, 5 microns) with the mobile phase CH3OH-H2O (60:40). The analytical mobile phase is CH3OH-phosphate buffer (pH6.86) (22:78). The UV detector was set at lambda 286 nm.

RESULTS

The method shows excellent linearity from 50 to 1,600 ng/ml for morphine and from 100 to 1,600 ng/ml for O6-monoacetylmorphine. The linear correlation coefficients were > 0.999. The relative standard deviations were < 4%. The limits of detection were 40 ng/ml for both morphine and O6-monoacetylmorphine.

CONCLUSION

The method described is sensitive, rapid, reproducible, and simple.

Concentrations of unconjugated morphine, codeine and 6-acetylmorphine in urine specimens from suspected drugged drivers

Concentrations of unconjugated morphine, codeine and 6-acetylmorphine (6-AM), the specific metabolite of heroin, were determined in urine specimens from 339 individuals apprehended for driving under the influence of drugs (DUID) in Sweden. After an initial screening analysis by immunoassay for 5-classes of abused drugs (opiates, cannabinoids, amphetamine analogs, cocaine metabolite and benzodiazepines), all positive specimens were verified by more specific methods. Opiates and other illicit drugs were analyzed by isotope-dilution gas chromatography-mass spectrometry (GC-MS). The limits of quantitation for morphine, codeine and 6-AM in urine were 20 ng/mL. Calibration plots included an upper concentration limit of 1000 ng/mL for each opiate. We identified the heroin metabolite 6-AM in 212 urine specimens (62%) at concentrations ranging from 20 ng/mL to > 1000 ng/mL. The concentration of 6-AM exceeded 1000 ng/mL in 79 cases (37%) and 31 cases (15%) were between 20 and 99 ng/mL. When 6-AM was present in urine the concentration of morphine was above 1000 ng/mL in 196 cases (92%). The concentrations of codeine in these same urine specimens were more evenly distributed with 35% being above 1000 ng/mL and 21% below 100 ng/mL. These results give a clear picture of the concentrations of unconjugated morphine, codeine and 6-acetylmorphine that can be expected in opiate-positive urine specimens from individuals apprehended for DUID after taking heroin.

Concentration ratios of morphine to codeine in blood of impaired drivers as evidence of heroin use and not medication with codeine

BACKGROUND

Both the illicit drug heroin and the prescription drug codeine are metabolized to morphine, which tends to complicate interpretation of opiate-positive samples. We report here the concentrations of morphine and codeine, the morphine/codeine ratios, and 6-acetylmorphine (6-AM) in blood specimens from individuals arrested for driving under the influence of drugs (DUID) in Sweden. The results were compared with positive findings of 6-AM in urine as evidence of heroin intake.

METHODS

In 339 DUID suspects, both blood and urine specimens were available for toxicologic analysis. In another 882 cases, only blood was available. All specimens were initially analyzed by immunoassay, and the positive results were verified by isotope-dilution gas chromatography-mass spectrometry. In routine casework, the limits of quantification (LOQs) for unconjugated opiates were 5 ng/g for blood and 20 microg/L for urine.

RESULTS

The median concentration of morphine in blood was 30 ng/g with 2.5 and 97.5 percentiles of 5 and 230 ng/g, respectively (n = 979). This compares with a median codeine concentration of 20 ng/g and 2.5 and 97.5 percentiles of 5 and 592 ng/g, respectively (n = 784). The specific metabolite of heroin, 6-AM, was identified in only 16 of 675 blood specimens (2.3%). This compares with positive findings of 6-AM in 212 of 339 urine samples (62%) from the same population of DUID suspects. When 6-AM was identified in urine, the morphine/codeine ratio in blood was always greater than unity (median, 6.0; range, 1-66). In 18 instances, 6-AM was present in urine, although morphine and codeine were below the LOQ in blood. The morphine/codeine ratio in blood was greater than unity in 85% of DUID cases when urine was not available (n = 506), and the median morphine and codeine concentrations were 70 ng/g and 10 ng/g, respectively. When morphine/codeine ratios in blood were less than unity (n = 76), the median morphine and codeine concentrations were 10 ng/g and 180 ng/g, respectively.

CONCLUSIONS

Only 2.3% of opiate-positive DUID suspects were verified as heroin users on the basis of positive findings of 6-AM in blood. A much higher proportion (62%) were verified heroin users from 6-AM identified in urine. When urine was not available for analysis, finding a morphine/codeine concentration ratio in blood above unity suggests heroin use and not medication with codeine. This biomarker indicated that 85% of opiate-positive DUID blood samples were from heroin users.

Detection of opiate use in a methadone maintenance treatment population with the CEDIA 6-acetylmorphine and CEDIA DAU opiate assays

Heroin, with a plasma half-life of approximately 5 min, is rapidly metabolized to 6-acetylmorphine (6-AM). 6-AM, a specific marker for heroin use, which also has a short half-life of only 0.6 h, is detected in urine for only a few hours after heroin exposure. Ingestion of poppy seeds and/or licit opiate analgesics can produce positive urine opiate tests. This has complicated the interpretation of positive opiate results and contributed to the decision to raise opiate cutoff concentrations and to require 6-AM confirmation in federally mandated workplace drug-testing programs. Microgenics Corp. has developed the CEDIA 6-AM assay, a homogeneous enzyme immunoassay for semiquantitative determination of 6-AM in human urine, in addition to its CEDIA DAU opiate assay. Urine specimens were collected 3 times per week from 27 participants enrolled in a clinical research trial evaluating a contingency management treatment program for heroin and cocaine abuse. Of the 1377 urine specimens screened, 261 (18.9%) were positive for opiates at > or = 300 ng/mL, 153 (11.1%) were positive for opiates at > or = 2000 ng/mL, and 55 (4.0%) were positive for 6-AM at > or = 10 ng/mL. For opiate-positive screens > or = 300 and > or = 2000 ng/mL, 91.3% and 80.8% confirmed positive for morphine or codeine at the respective gas chromatography-mass spectrometry (GC-MS) cutoffs. All specimens screening positive for 6-AM also confirmed positive by GC-MS at > or = 10 ng/mL. Increasing the opiate screening and confirmation cutoffs for the federal workplace drug-testing program resulted in 8% fewer opiate-positive tests; however, recent heroin use was not affected by this change.

Urinary excretion profiles for total morphine, free morphine, and 6-acetylmorphine following smoked and intravenous heroin

Heroin is one of the major target drugs in workplace drug-testing programs because of its history of abuse, liability, and continued negative social impact. This study was a comprehensive examination of pharmacokinetics, pharmacodynamics, detection times, opiate immunoassay performance, and urine excretion profiles following single doses of heroin administered to human subjects via smoking and intravenous routes. Studies of the first four components of this investigation were previously published. This article describes the urine excretion profiles. Total morphine (Tmor), free morphine (Fmor), and 6-acetylmorphine (6-AM) were measured by gas chromatography-mass spectrometry (GC-MS) in 920 urine samples collected from 11 male human subjects following single doses of heroin. Eight received intravenous doses of 3, 6, and 12 mg heroin HCI and four smoked 3.5-, 5.2-, 7-, 10.5-, or 13.9-mg doses of heroin (base). In addition, 183 urine-based blind quality-control samples were added to the study set to assess assay performance. Creatinine was also measured in each sample by a colorimetric technique. The parameters studied were not significantly dependent on route of administration. Excretion half-life mean +/- SD for Tmor was 3.11 +/- 0.30 h. Range (median) of peak urine concentrations, time to peak, time to last positive sample for low cutoff (300 ng/mL) and high cutoff (2000 ng/mL) for Tmor following lower doses (< or = 7 mg) were, respectively, 1392-9250 (3620) ng/mL, 1.2-6.2 (2.3) h, 7.4-31.9 (7.4) h, and 0-10.1 (4.3) h. Following higher doses (> 10 mg) they were 2065-29,030 (16,470) ng/mL, 2.3-9.3 (4.5) h, 10.7-53.5 (34.4) h, 2.3-22.3 (8.3) h. Fmor peaked in the same sample as Tmor. Range (median) of peak Fmor concentrations and time to last positive using a cutoff of 100 ng/mL for low and high doses were, respectively, 117-1160 (415) ng/mL, 1.2-10.1 (4.5) h and 150-2580 (1400) ng/mL, 2.3-29.1 (9.3) h. The range (median) of peak urine concentrations for 6-AM was 6.1-568 (124) ng/mL. In general, the first urine void had the peak 6-AM concentration and was the only specimen positive at a 10-ng/mL cutoff. As previously reported urine concentrations varied greatly between subjects and within subjects with time after dosing but were much more predictable when values were reported as amount of drug per unit of creatinine. The range (median) values for percent of heroin excreted into urine as Tmor was 12.8-88.5% (51.0).

Detection time of drugs of abuse in urine

Estimating the detection time of a drug in urine is complex because of many different influencing factors and the lack of experimental data. Detection times vary depending on dose and route of administration, metabolism and characteristics of the screening and confirmation assays. Using a cut-off value of 1000 ng/mL, urinary samples can be positive for amphetamine for up to 5 days after intake of the drug. At the lower 300 ng/mL cut-off, amphetamine will be detectable one day longer. Very few data are available for designer amphetamines. After smoking one marijuana cigarette, THCCOOH (9-carboxy-delta 9 tetrahydrocannabinol) is detectable (using a screening cut-off of 50 ng/mL) for 2-4 days. More frequent use will be detectable for almost 1 month, exceptionally 3 months. Immunoassays to detect cocaine are targeted against the metabolite benzoylecgonine and use a cut-off of 300 ng/mL. An intravenous dose of 20 mg cocaine can be detected for 1.5 days. Street doses (administered via different routes) are detectable up to 1 week, and extremely high doses up to 3 weeks. Heroin rapidly metabolizes to 6-acetylmorphine and morphine. Immunoassays for heroin are calibrated with morphine but important cross-reactivity occurs and positive results must be confirmed by GC-MS. Experimental data for total morphine using a cut-off of 300 ng/mL suggest a detection time of 1 to 1.5 days for relatively low doses of heroin (3-12 mg) administered via i.v., IN or i.m. route.

Detection times and analytical performance of commercial urine opiate immunoassays following heroin administration

The Federal Workplace Drug Testing Program changed urine screening and confirmation cutoff concentrations for opiate testing from 300 to 2000 ng/mL in 1998. Morphine was the designated target compound. An additional heroin metabolite, 6-acetylmorphine (6-AM), was added to the testing procedure with a cutoff concentration > or = 10 ng/mL. Testing of 6-AM was required if morphine was positive to assist in medical review. A comparison of the new opiate cutoff concentrations was made with the older cutoff concentration at 300 ng/mL. Six commercial opiate immunoassays, four with a 300-ng/mL cutoff, ONLINE, EMIT, CEDIA and AxSym, and two with 2000-ng/mL cutoffs, ONLINE and EMIT, were selected to test 920 urine samples collected from 11 male human subjects following single doses of heroin. Eight received intravenous doses of 3, 6, and 12 mg heroin HCl and four smoked 3.5-, 5.2-, 10.5-, or 13.9-mg doses of heroin (base). In addition, 183 urine-based blind quality-control specimens were added to the study set to assess linearity, cross-reactivity, and interference. Total morphine, free morphine, and 6-AM were measured in each sample by gas chromatography-mass spectrometry (GC-MS). Linearity, cross-reactivity, and interference results for each immunoassay are described. Detection times, sensitivity, specificity, and efficiency of each assay were determined using data from the specimens collected after heroin administration. Detection times for morphine using the 300-ng/mL cutoff assays was approximately 12 h for low dose and 24 to 48 h for higher doses of heroin. For the two 2000-ng/mL cutoff concentration assays detection time was about 12 h. This was also the detection time for 6-AM by GC-MS. ONLINE had the lowest sensitivity, 60-74%, highest specificity, 98.8-100%, and least interference from a selection of common over-the-counter drugs and opioids. Increasing the cutoff to 2000 ng/mL from 300 ng/mL increased efficiencies of the assays from 72.7 to 82.6% to over 97%.

A sensitive solid-phase fluoroimmunoassay for detection of opiates in urine

An automated flow fluorometer designed for kinetic binding analysis was adapted to develop a solid-phase competitive fluoroimmunoassay for urinalysis of opiates. The solid phase consisted of polymer beads coated with commercial monoclonal antibodies (MAbs) raised against morphine. Fluorescein-conjugated morphine (FL-MOR) was used as the fluorescein-labeled hapten. The dissociation equilibrium constant (K(D)) for the binding of FL-MOR to the anti-MOR MAb was 0.23 nM. The binding of FL-MOR to the anti-MOR MAb reached steady state within minutes and was displaced effectively by morphine and other opiates. Morphine-3-glucuronide (M3G), the major urinary metabolite of heroin and morphine, competed effectively with FL-MOR in a concentration-dependent manner for binding to the antimorphine MAb and was therefore used to construct the calibration curve. The sensitivity of the assay was 0.2 ng/mL for M3G. The assay was effective at concentrations of M3G from 0.2 to 50 ng/mL, with an IC50 of 2 ng/mL. Other opiates and heroin metabolites that showed >50% crossreactivity when present at 1 microg/mL included codeine, morphine-6-glucuronide, and oxycodone. Methadone showed very low crossreactivity (<5%), which is a benefit for testing in patients being treated for opiate addictions. The high sensitivity of the assay and the relatively high cutoff value for positive opiate tests allows very small sample volumes (e.g., in saliva or sweat) to be analyzed. A double-blind comparison using 205 clinical urine samples showed good agreement between this single-step competitive assay and a commercially performed enzyme multiplied immunoassay technique for the detection of opiates and benzoylecgonine (a metabolite of cocaine).

Elimination of the interferences by keto-opiates in the GC-MS analysis of 6-monoacetylmorphine

A simple procedure to eliminate the interference from keto-opiates in the analysis of 6-monoacetylmorphine (6-MAM) by gas chromatography-mass spectrometry is described. The pretreatment of urine samples with sodium bisulfite followed by solid-phase extraction results in the elimination of the bisulfite addition products formed from the reaction of the bisulfite ions with the carbonyl carbon of the keto-opiates. This simple procedure results in the accurate quantitation of 6-MAM at a concentration of 4 ng/mL in the presence of keto-opiates up to 10,000 ng/mL.

Distinction among eight opiate drugs in urine by gas chromatography-mass spectrometry

Opiates are commonly abused substances, and forensic urine drug-testing for them requires gas chromatographic-mass spectrometric (GC-MS) confirmation. There are also medical reasons to test urine for opiates, and confirmation procedures other than GC-MS are often used for medical drug-testing. A thin-layer chromatographic (TLC) method distinguishes morphine, acetylmorphine, hydromorphone, oxymorphone, codeine, dihydrocodeine, hydrocodone, and oxycodone in clinical specimens. In certain clinical circumstances, GC-MS confirmation is requested for opiates identified by TLC, but, to our knowledge, no previous report examines all of the above opiates in a single GC-MS procedure. We find that they can be distinguished by GC-MS analyses of trimethylsilyl (TMS) ether derivatives, and identities of 6-keto opiates can be further confirmed by GC-MS analysis of methoxime (MO)-TMS derivatives. Inclusion of deuterium-labeled internal standards permits identification of the opiates in urine at concentrations below the TLC cutoff level of 600 ng/ml, and the GC-MS assay is linear over a concentration range that spans that level. This GC-MS procedure has proved useful as a third-stage identification step in a medical drug-testing sequence involving prior immunoassay and TLC.

GC-MS confirmation of codeine, morphine, 6-acetylmorphine, hydrocodone, hydromorphone, oxycodone, and oxymorphone in urine

A procedure for the simultaneous confirmation of codeine, morphine, 6-acetylmorphine, hydrocodone, hydromorphone, oxycodone, and oxymorphone in urine specimens by gas chromatography-mass spectrometry (GC-MS) is described. After the addition of nalorphine and naltrexone as the two internal standards, the urine is hydrolyzed overnight with beta-glucuronidase from E. coli. The urine is adjusted to pH 9 and extracted with 8% trifluoroethanol in methylene dichloride. After evaporating the organic, the residue is sequentially derivatized with 2% methoxyamine in pyridine, then with propionic anhydride. The ketone groups on hydrocodone, hydromorphone, oxycodone, oxymorphone, and naltrexone are converted to their respective methoximes. Available hydroxyl groups on the O3 and O6 positions are converted to propionic esters. After a brief purification step, the extracts are analyzed by GC-MS using full scan electron impact ionization. Nalorphine is used as the internal standard for codeine, morphine, and 6-acetylmorphine; naltrexone is used as the internal standard for the 6-keto-opioids. The method is linear to 2000 ng/mL for the 6-keto-opioids and to 5000 ng/mL for the others. The limit of quantitation is 25 ng/mL in hydrolyzed urine. Day-to-day precision at 300 and 1500 ng/mL ranged between 6 and 10.9%. The coefficients of variation for 6-acetylmorphine were 12% at both 30 and 150 ng/mL. A list of 38 other basic drugs or metabolites detected by this method is tabulated.

Detection of 6-acetylmorphine in vitreous humor and cerebrospinal fluid--comparison with urinary analysis for proving heroin administration in opiate fatalities

The concentrations of morphine and 6-acetylmorphine (6-AM) in urine, cerebrospinal fluid (CSF), and vitreous humor (VH) and the morphine concentrations in blood were determined by gas chromatography-mass spectrometry for 29 fatalities after abuse of heroin either alone or in combination with alcohol and other drugs. 6-AM was found above a quantitation limit of 1 ng/mL in urine in 89% of the cases, in CSF in 68% of the cases, and in VH in 75% of the cases. The 6-AM concentrations in CSF (mean, 10 ng/mL) and VH (mean, 17 ng/mL) were in general much smaller than in urine (mean, 170 ng/mL); therefore, the different pharmacokinetic behavior of the fluids is discussed. There is no uniformity between the three fluids with respect to the presence or absence of 6-AM. Therefore, CSF or VH may be used as complementary or alternative materials to urine in order to prove heroin uptake in opiate fatalities.

[Determination of metabolites of heroin in urine and discrimination of heroin abuse]

This article describes a sensitive method that detects morphine, 6-monoacetylmorphine, morphine-3-glucuronide and codeine in urine for qualifying the abuse of heroin. The analytes were extracted by solid phase C18. The limits of detection (LOD) for morphine and codeine were 50 ng/ml and 50 ng/ml, respectively. The RSD of morphine and codeine were 11.3% (n = 5), and 14.2% (n = 5) respectively. For urine, it does not need to be hydrolyzed before extracted, and for all analytes, also need not to be derivated. The difference ratio of morphine and codeine in the chromatography can be used to discriminate between the abuse of heroin and the administration of compound liquorice mixture.

Analysis of morphine and morphine-3beta-D glucuronide in human urine by capillary zone electrophoresis with minimal sample pretreatment

The presence of two of the metabolites of heroin, free morphine and morphine 3-beta-D-glucuronide (MO3G) in acidified urine samples was simultaneously determined by capillary zone electrophoresis (CZE). In a run buffer containing 50 mM sodium borate and 250 mM boric acid (pH 8.6), free morphine migrates before a group of neutral compounds (peak N) in urine, which move with the velocity of electro-osmotic flow. In contrast, the glucuronidated form is negatively charged and migrates behind peak N. Both analytes can be precisely identified within their respective analytical window by their migration time with respect to peak N. The on-line multi-wavelengths scanning of the peak permits further confirmation. The detection sensitivity of both analytes was increased three-four fold if the samples were introduced with electro-injection as compared with hydrodynamic injection. Limits of detection (LOD) of free and conjugated morphine using electro-injection were 200 ng/mL and 500 ng/mL, respectively, determined at a 3:1 signal to noise ratio. A dramatic increase of free morphine was observed after acid hydrolysis of the urine concomitantly with the decrease of the glucuronidated form. We conclude that CZE is a rapid, simple, sensitive and useful screening technique for detection of heroin metabolites in the urine.

A practical approach to determine cutoff concentrations for opiate testing with simultaneous detection of codeine, morphine, and 6-acetylmorphine in urine

BACKGROUND

Both the Department of Defense (DoD) and the Department of Health and Human Services (DHHS) currently require two confirmation tests to verify use of heroin, one test for total morphine and a separate test for 6-acetylmorphine (6-AM). Our aim was to determine appropriate free-codeine, free-morphine, and 6-AM cutoff concentrations that could be substituted for total-morphine, total-codeine, and 6-AM cutoff concentrations and to develop a less labor-intensive method for measuring codeine, morphine, and 6-AM.

METHODS

Urine samples containing opiates were extracted, derivatized, and analyzed using gas chromatography-mass spectrometry with selective ion monitoring.

RESULTS

The limits of detection for codeine, morphine, and 6-AM were 6, 5, and 0.5 microg/L, respectively. Recoveries were >90%. Quantification was linear over the concentration range of 6-1000 microg/L for codeine, 5-5000 microg/L for morphine, and 0.5-800 microg/L for 6-AM. Cutoff concentrations for confirmation of opiates were 100, 100, and 10 microg/L for free codeine, free morphine, and 6-AM.

CONCLUSION

The proposed cutoff concentrations for free morphine and 6-AM provide better detection windows for morphine and heroin use than the cutoff concentrations for total morphine and 6-AM used at present. Detection of free codeine, instead of total codeine, simplifies interpretation of codeine use. The single-extraction method enables simultaneous, less labor-intensive analysis of morphine, codeine, and 6-AM.

Pharmacokinetics of morphine and its glucuronides following intravenous administration of morphine in patients undergoing continuous ambulatory peritoneal dialysis

BACKGROUND

Conjugation with glucuronic acid represents the major route of biotransformation of morphine. The glucuronides morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) are eliminated via the kidneys. Therefore, chronic renal failure should affect the disposition of M3G and M6G. Numerous patients undergoing long-term continuous ambulatory peritoneal dialysis (CAPD) require pain treatment with morphine. There are only limited data available about the disposition of morphine and its active metabolites M6G and M3G in patients on CAPD. We therefore investigated the pharmacokinetics of morphine and its metabolites in CAPD patients.

METHODS

This was a single intravenous dose pharmacokinetic study in 10 CAPD patients (1 female, 9 male, age 31-69 years). Morphine-hydrochloride (Mo) (10 mg) was administered intravenously. Serum, urine, and dialysate samples were collected during 24 h. GC-MS-MS and HPLC-MS methods were used to quantify respectively morphine and morphine glucuronides.

RESULTS

While systemic clearance of morphine (1246+/-240 ml/min) was in the range observed in patients with normal kidney function, both M3G and M6G showed substantial accumulation. The area under the concentration-time curve (AUC) ratio of M3G:Mo (33.4+/-7.1) and of M6G:Mo (12.2+/-3.2) was 5.5 and 13.5 times higher than in patients with normal kidney function. Renal clearances of morphine, M3G, and M6G (morphine 3.0+/-2.5 ml/min; M3G 3.9+/-2.2 ml/min; M6G 3.6+/-2.2 ml/min) and dialysate clearances (morphine 4.1+/-1.3 ml/min; M3G 3.2+/-0.7 ml/min; M6G 3.0+/-0.8 ml/min) were extremely low. Therefore the accumulation of M6G and M3G is readily explained by kidney failure which is not compensated by CAPD.

CONCLUSION

Accumulation of M3G and M6G is due to the substantially lowered clearance by residual renal function and peritoneal dialysis. In view of the accumulation of potential active metabolites, subsequent investigations have to assess the frequency of side-effects in patients on CAPD.

[Verification and determination of opiates in the urine and blood with thin-layer chromatography followed by densitometry in fatal cases of drug abuse]

Urine and blood concentrations of free and total morphin or 6-monoacetylmorphin were presented in fatal cases of morphin type opiates abuse. A solid phase extraction method was developed for isolation of drugs and their metabolities from biological material which used Separcol small columns with non-polar contents SI C 18T. Thin layer chromatography with densitometry anabled screening for quality evaluations. Resultes were compared with those obtained by fluoropolarizing immunodetection on Abbotts TDxFLx device. Possibility and cause of false positive results were discussed when using initial, screening, commercially available immunotests.

An evaluation of the role of ROC plots in the prediction of heroin use from total codeine and total morphine concentrations in urine

A diagnostic system to predict the presence of 6-acetylmorphine (6AM) in opiate-positive urines was recently proposed. A twofold criterion based on the total morphine concentration and the total codeine to total morphine concentration ratio was identified. Using relative operating characteristic (ROC) analysis, it was determined that the diagnostic system had a sensitivity of 92%, a specificity of 79%, and an overall accuracy of 73%. We applied similar decision criteria to a study population of 125 opiate-positive urines collected from criminal justice clients of a West Coast reference laboratory. ROC analysis on this population produced very different results: a sensitivity of 91%, a specificity of 49%, and an accuracy of 45%. These data illustrate the importance of choosing a representative study population without any selection biases that may compromise the validity of the accuracy measure. The ROC plot is an important tool for assessing a clinical test's performance, but in order for toxicologists and Medical Review Officers to benefit from the diagnostic test results, they must also know the predictive value (based on test accuracy and the prevalence of heroin use) of the test results. They need to know how well the test predicts the presence of 6AM, and therefore, the illicit use of heroin, in the population of interest whether it be workplace, criminal justice, hospital emergency department clients, or a combination of all populations.

Opiate concentrations following the ingestion of poppy seed products--evidence for 'the poppy seed defence'

The universally accepted 300 ng/ml cut-off limit for opiate assays stated to be mandatory for all drug screening laboratories by the Substance Abuse and Mental Health Services Administration, has been questioned recently due to positive results being obtained following the ingestion of poppy seed containing food products. To establish the plausibility of the 'the poppy seed defence' the concentrations of codeine, norcodeine, morphine, normorphine and thebaine (a potential marker for seed ingestion) in several varieties of poppy seeds from different countries were quantified by GC-MS. The country of origin of the seed specimen analysed and the preparation of the seeds prior to their culinary use was found to influence the alkaloid concentration determined. The maximum morphine and codeine concentrations determined in the seeds were found to be 33.2 and 13.7 micrograms/g seed respectively. In addition, thebaine concentrations were found to vary with each seed sample analysed. Following the consumption of bread rolls (mean 0.76 g seed covering per roll) by four subjects, all urine specimens analysed produced negative results (using the Dade Bebring EMIT II opiate screening assay) with the exception of one subject (body weight 63.0 kg) who consumed two poppy seed rolls. In this subject opiate positive screening results were obtained for up to 6 h post ingestion with maximum urinary morphine and codeine concentrations of 832.0 ng/ml (@ 2-4 h post ingestion) and 47.9 ng/ml (@ 0-2 h post ingestion) respectively being achieved. Following the ingestion of poppy seed cake containing an average of 4.69 g of seed per slice by four individuals, opiate positive screening results were obtained for up to 24 h. In one subject (dose equivalent to 0.07 g poppy seed/kg body weight) maximum urinary morphine and codeine concentrations of 302.1 ng/ml (@ 0-2 h) and 83.8 ng/ml (@ 2-4 h) respectively were recorded. The elimination of thebaine was found to vary widely between individuals, therefore suggesting that its absence from a specimen is not necessarily indicative of opiate abuse. These findings demonstrate that the poppy seed defence could be used as an argument in medico-legal and employment medical cases. Great care should therefore be taken when interpreting the data produced when screening for opiates.

The detection of acetylcodeine and 6-acetylmorphine in opiate positive urines

Acetylcodeine (AC), an impurity of illicit heroin synthesis, was investigated as a urinary biomarker for detection of illicit heroin use. One hundred criminal justice urine specimens that had been confirmed positive by GC/MS for morphine at concentrations > 5000 ng/ml were analyzed for AC, 6-acetylmorphine (6AM), codeine, norcodeine and morphine. The GC/MS analysis was performed by solid phase extraction and derivatization with propionic anhydride. Total codeine and morphine concentrations were determined by acid hydrolysis and liquid/liquid extraction. AC was detected in 37 samples at concentrations ranging from 2 to 290 ng/ml (median, 11 ng/ml). 6AM was also present in these samples at concentrations ranging from 49 to 12 600 ng/ml (median, 740 ng/ml). Of the 63 specimens negative for AC, 36 were positive for 6AM at concentrations ranging from 12 to 4600 ng/ml (median, 124 ng/ml). When detected, the AC concentrations were an average of 2.2% (0.25 to 10.2%) of the 6AM concentrations. There was a positive relationship between AC concentrations and 6AM concentrations (r = 0.878). Due to its very low concentration in urine, AC was found to be a much less reliable biomarker for illicit heroin use than 6AM in workplace or criminal justice urine screening programs. However, AC detection could play an important role in determining if addicts in heroin maintenance programs are supplementing their supervised diacetylmorphine doses with illicit heroin.

Near fatal intoxication with controlled-release morphine tablets in a depressed woman

BACKGROUND

A 46-year-old woman suffering from a reactive depression was admitted to the emergency room in coma and with severe respiratory failure. She later developed cardiovascular instability and general convulsions. Two days following admission the patient had no respiratory effort but was able to communicate in writing that she had ingested a large amount of controlled-release morphine tablets. Following treatment with naloxone she was successfully weaned from the respirator the next day.

METHODS

Sampling for determination of plasma and urine concentrations of morphine and its metabolites morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) was started 60 h after the presumed time of intake and continued up to 8 days after admission.

RESULTS

The initial plasma concentrations of morphine, M3G and M6G were 2160, 13100 and 2330 nM, respectively, compatible with a lethal dose in an opioid-naive patient. The urinary recovery of morphine, M3G and M6G corresponded to 6.8 mmol, equivalent to an oral intake of at least 2500 mg.

CONCLUSION

The plasma concentrations of morphine and morphine metabolites documented in this case, indicative of considerable absorption of drug, demonstrate that prolonged observation is necessary following intoxications with controlled-release morphine tablets. This case also highlights the importance of continuous follow-up of oral morphine therapy, so that unused drug is not left unaccounted for in the patient's home.