Oral fluid collection: the neglected variable in oral fluid testing

The potential to use oral fluid as a drug-testing specimen has been the subject of considerable scientific interest. The ease with which specimens can be collected and the potential for oral fluid (OF) drug concentrations to reflect blood-drug concentrations make it a potentially valuable specimen in clinical as well as forensic settings. However, the possible effects of the OF collection process on drug detection and quantification has often been over looked. Several studies have documented that drug-contamination of the oral cavity may skew oral fluid/blood drug ratios and confound interpretation when drugs are smoked, insufflated or ingested orally. OF pH is predicted to have an effect on the concentration of drugs in OF. However, in a controlled clinical study, the effect of pH was less than that of collection technique. Mean codeine OF concentrations in specimens collected a non-stimulating control method were 3.6 times higher than those in OF collected after acidic stimulation. Mean codeine concentrations were 50% lower than control using mechanical stimulation and 77% of control using commercial collection devices. Several factors should be considered if a commercial OF collection device is used. In vitro collection experiments demonstrated that the mean collection volume varied between devices from 0.82 to 1.86 mL. The percentage of the collected volume that could be recovered from the device varied from 18% to 83%. In vitro experiments demonstrated considerable variation in the recovery of amphetamines (16-59%), opiates (33-50%), cocaine and benzoylecgonine (61-97%), carboxy-THC (0-53%) and PCP (9-56%). Less variation in collection volume, volume recovered and drug recovery was observed intra-device. The THC stability was evaluated in a common commercial collection protocol. Samples in the collection buffer were relatively stable for 6 weeks when stored frozen. However, stability was marginal under refrigerated conditions and poor at room temperature. Very little has been published on the efficacy of using IgG concentration, or any other endogenous marker, as a measure of OF specimen validity. Preliminary rinsing experiments with moderate (50 mL and 2 x 50 mL) volumes of water did not reduce the OF IgG concentration below proposed specimen validity criteria. In summary, obvious and more subtle variables in the OF collection may have pronounced effects on OF-drug concentrations. This has rarely been acknowledged in the literature, but should to be considered in OF drug testing, interpretation of OF-drug results and future research studies.     

Oral fluid collection: The neglected variable in oral fluid testing

The potential to use oral fluid as a drug-testing specimen has been the subject of considerable scientific interest. The ease with which specimens can be collected and the potential for oral fluid (OF) drug concentrations to reflect blood–drug concentrations make it a potentially valuable specimen in clinical as well as forensic settings. However, the possible effects of the OF collection process on drug detection and quantification has often been over looked. Several studies have documented that drug-contamination of the oral cavity may skew oral fluid/blood drug ratios and confound interpretation when drugs are smoked, insufflated or ingested orally. OF pH is predicted to have an effect on the concentration of drugs in OF. However, in a controlled clinical study, the effect of pH was less than that of collection technique. Mean codeine OF concentrations in specimens collected a non-stimulating control method were 3.6 times higher than those in OF collected after acidic stimulation. Mean codeine concentrations were 50% lower than control using mechanical stimulation and 77% of control using commercial collection devices.Several factors should be considered if a commercial OF collection device is used. In vitro collection experiments demonstrated that the mean collection volume varied between devices from 0.82 to 1.86 mL. The percentage of the collected volume that could be recovered from the device varied from 18% to 83%. In vitro experiments demonstrated considerable variation in the recovery of amphetamines (16–59%), opiates (33–50%), cocaine and benzoylecgonine (61–97%), carboxy-THC (0–53%) and PCP (9–56%). Less variation in collection volume, volume recovered and drug recovery was observed intra-device. The THC stability was evaluated in a common commercial collection protocol. Samples in the collection buffer were relatively stable for 6 weeks when stored frozen. However, stability was marginal under refrigerated conditions and poor at room temperature. Very little has been published on the efficacy of using IgG concentration, or any other endogenous marker, as a measure of OF specimen validity. Preliminary rinsing experiments with moderate (50 mL and 2 × 50 mL) volumes of water did not reduce the OF IgG concentration below proposed specimen validity criteria. In summary, obvious and more subtle variables in the OF collection may have pronounced effects on OF–drug concentrations. This has rarely been acknowledged in the literature, but should to be considered in OF drug testing, interpretation of OF–drug results and future research studies.     

The recovery of illicit drugs from oral fluid sampling devices

Testing for drugs in oral fluid is a convenient procedure for determining recent drug use. A number of issues are still to be resolved and this paper investigates the effects of storage systems on drug stability and recovery using three different collection devices supplied by Cozart, Immunalysis and Microgenics (third party). Drugs were analysed using a range of immunoassay systems followed by MS confirmation and quantitation. The reproducibility of the weight of specimen collected was excellent (CV<10%) for the three collection devices tested. Of the three systems studied, only the Cozart product gave acceptable recovery of THC from drug-spiked oral fluid. A combination of Cozart, Immunalysis and Diagnostix immunoassays with the Cozart collection system gave the most sensitive and discriminating screening assays for the drugs studied, namely THC, benzodiazepines, methamphetamine and morphine. Storage at either 5 degrees C or room temperature had no significant effect on drug recoveries.     

Analysis of cannabis in oral fluid specimens by GC-MS with automatic SPE

Methamphetamine (MA) is the most commonly abused drug in Korea, followed by cannabis. Traditionally, MA analysis is carried out on both urine and hair samples and cannabis analysis in urine samples only. Despite the fact that oral fluid has become increasingly popular as an alternative specimen in the field of driving under the influence of drugs (DUID) and work place drug testing, its application has not been expanded to drug analysis in Korea. Oral fluid is easy to collect and handle and can provide an indication of recent drug abuse.In this study, we present an analytical method using GC–MS to determine tetrahydrocannabinol (THC) and its main metabolite 11-nor-Δ⁹-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in oral fluid. The validated method was applied to oral fluid samples collected from drug abuse suspects and the results were compared with those in urine. The stability of THC and THC-COOH in oral fluid stored in different containers was also investigated.Oral fluid specimens from 12 drug abuse suspects, submitted by the police, were collected by direct expectoration. The samples were screened with microplate ELISA. For confirmation they were extracted using automated SPE with mixed-mode cation exchange cartridge, derivatized and analyzed by GC-MS using selective ion monitoring (SIM).The concentrations of THC and THC-COOH in oral fluid showed a large variation and the results from oral fluid and urine samples from cannabis abusers did not show any correlation. Thus, detailed information about time interval between drug use and sample collection is needed to interpret the oral fluid results properly. In addition, further investigation about the detection time window of THC and THC-COOH in oral fluid is required to substitute oral fluid for urine in drug testing.     

Analysis of Delta9-tetrahydrocannabinol in oral fluid samples using solid-phase extraction and high-performance liquid chromatography-electrospray ionization mass spectrometry

An analytical method using solid-phase extraction (SPE) and high-performance liquid chromatography-mass spectrometry (LC-MS) has been developed and validated for the confirmation of Delta(9)-tetrahydrocannabinol (THC) in oral fluid samples. Oral fluid was extracted using Bond Elut LRC-Certify solid-phase extraction columns (10 cm(3), 300 mg) and elution performed with n-hexane/ethyl acetate. Quantitation made use of the selected ion-recording mode (SIR) using the most abundant characteristic ion [THC+H(+)], m/z 315.31 and the fragment ion, m/z 193.13 for confirmation, and m/z 318.00 for the protonated internal standard, [d(3)-THC+H(+)]. The method proved to be precise for THC, in terms of both intra-day and inter-day analyses, with coefficients of variation less than 10%, and the calculated extraction efficiencies for THC ranged from 76 to 83%. Calibration standards spiked with THC between 2 and 100 ng/mL showed a linear relationship (r(2)=0.999). The method presented was applied to the oral fluid samples taken from the volunteers during the largest music event in Portugal, named Rock in Rio-Lisboa. Oral fluid was collected from 40 persons by expectoration and with Salivette. In 55% of the samples obtained by expectorating, THC was detected with concentration ranges from 1033 to 6552 ng/mL and in 45% of cases THC was detected at concentrations between 51 and 937 ng/mL. However, using Salivette collection, 26 of the 40 cases had an undetectable THC.     

The effect of sodium fluoride preservative and storage temperature on the stability of 6-acetylmorphine in horse blood, sheep vitreous and deer muscle

This study examined the in vitro stability of 6-acetylmorphine (6AM) in horse blood, sheep vitreous humour (VH) and homogenised deer muscle stored under different storage conditions. The stability of 6AM in horse blood is of interest because many toxicological laboratories utilise this matrix for the preparation of blood calibration and check standards and the latter are typically stored during routine use. Data on the storage stability of 6AM in human VH is extremely limited and no data has been reported in muscle. In the absence of human samples, 6AM stability was demonstrated in sheep vitreous and deer muscle. Blood and VH were stored with and without NaF at room temperature (RT), 4 and -18°C for 84 days. Muscle tissue homogenates were prepared in water with and without NaF and also in phosphate buffer (pH 6.0) containing NaF. Homogenates were stored for 31 days at RT, 4 and -18°C. Morphine and 6AM were extracted using SPE and quantified by GC-ion trap-MS/MS. In the absence of NaF, 6AM could not be detected after 7 and 14 days in blood stored at RT and 4°C, respectively. Although at -18°C 6AM was stable for 7 days (12% loss), only 54% was detected by day 84. The addition of NaF to horse blood increased 6AM stability substantially at every temperature. Further, the rate of degradation was found to be significantly slower in blood preserved with 2% NaF compared with 1% NaF (p=.05). 6AM was stable for the study period in preserved blood (1 and 2% NaF) stored at -18°C. For laboratories utilising horse blood in the preparation of standards, preservation with 1% NaF (minimum) and storage at -18°C is recommended. The addition of NaF to VH was essential for 6AM stability. Irrespective of temperature substantial losses (≥ 42%) were observed in unpreserved sheep VH by day 7. In preserved VH the concentration declined by only 22% on day 7 following storage at RT and no loss observed in VH stored at 4 and -18°C at the same time. In muscle, 6AM was stable for 7 days in preserved samples stored at RT and in all samples stored at 4°C and below. The addition of NaF increased the stability of 6AM substantially in muscle. The increased stability of 6AM in VH and muscle preserved with fluoride was attributed to inhibition of bacterial action and the subsequent reduction in the rate of putrefaction of these tissues.     

Development and validation of the Cozart DDS oral fluid collection device

The testing of oral fluid for drugs of abuse has increased significantly over recent years and is now commonplace in drug rehabilitation clinics, the workplace, prisons and custody suites. The global problem of identifying drugged drivers has also led to an increase in oral fluid testing at the roadside. The main requirements for the implementation of roadside drug testing are a rapid sample collection time, collection of a known sample volume and recovery of drugs from the collection device. We report here the development of the Cozart^® DDS oral fluid collector, an oral fluid collector that combines rapid and adequate sample collection with satisfactory drug recovery. Oral fluid was collected from drug users (n = 134) and drug-free individuals (n = 137), using the Cozart^® DDS oral fluid collector. The mean time for the completion of collection (full coloration of the sample presence indicator) was 34 s for drug-free individuals and 44 s for drug users. The average volume collected was 0.34 mL (n = 271). No chemical stimulant (to induce salivation) was used to achieve the collection times observed in either the drug-free or the drug-taking sample populations. Drugs were extracted from the collector using the Cozart^® DDS buffer and drug recovery was determined by Cozart^® enzyme immunoassays. The recovery studies showed that for amphetamine, Δ⁹THC, cocaine, methadone, methamphetamine, morphine and temazepam over 90% of the drug in the sample was eluted from the collector. The Cozart^® DDS oral fluid collector provides a reliable mechanism for the collection of oral fluid at the roadside that achieves the rapid collection times required.     

Comparison of point-of-collection screening of drugs of abuse in oral fluid with a laboratory-based urine screen.

Oral fluid is becoming increasingly useful for the detection of drugs, since it is a non-invasive specimen to collect and, because collection is directly observed, it is difficult to adulterate. A point-of-collection (POCT) oral fluid drug analysis kit has been developed for use in many drug testing situations. This paper summarizes the results of field evaluations of the ORALscreen System for screening of drugs in oral fluid. The ORALscreen System consists of an oral fluid collection device and a test device containing a lateral flow membrane immunoassay system. Paired samples (oral fluid and urine) were collected from drug users and the results from the ORALscreen POCT system were compared to urine screening results conducted in a licensed laboratory. The results demonstrate that the ORALscreen System has excellent percent agreement with the laboratory-based urine screening test results for the detection of cocaine and opiates through 2.5-3 days following drug use, respectively. Tetrahydrocannabinol (THC) was detected by ORALscreen on the day of use and 1 day after use. Good correlation between urine and oral fluid screening results was observed for the methamphetamine positive samples; however, the number of days following drug use was not determined.     

Analysis of Δ-tetrahydrocannabinol in oral fluid samples using solid-phase extraction and high-performance liquid chromatography–electrospray ionization mass spectrometry

An analytical method using solid-phase extraction (SPE) and high-performance liquid chromatography–mass spectrometry (LC–MS) has been developed and validated for the confirmation of Δ⁹-tetrahydrocannabinol (THC) in oral fluid samples. Oral fluid was extracted using Bond Elut LRC-Certify solid-phase extraction columns (10 cm³, 300 mg) and elution performed with n-hexane/ethyl acetate. Quantitation made use of the selected ion-recording mode (SIR) using the most abundant characteristic ion [THC + H⁺], m/z 315.31 and the fragment ion, m/z 193.13 for confirmation, and m/z 318.00 for the protonated internal standard, [d₃-THC + H⁺]. The method proved to be precise for THC, in terms of both intra-day and inter-day analyses, with coefficients of variation less than 10%, and the calculated extraction efficiencies for THC ranged from 76 to 83%. Calibration standards spiked with THC between 2 and 100 ng/mL showed a linear relationship (r² = 0.999). The method presented was applied to the oral fluid samples taken from the volunteers during the largest music event in Portugal, named Rock in Rio-Lisboa. Oral fluid was collected from 40 persons by expectoration and with Salivette^®. In 55% of the samples obtained by expectorating, THC was detected with concentration ranges from 1033 to 6552 ng/mL and in 45% of cases THC was detected at concentrations between 51 and 937 ng/mL. However, using Salivette^® collection, 26 of the 40 cases had an undetectable THC.     

The effect of sodium fluoride preservative and storage temperature on the stability of cocaine in horse blood, sheep vitreous and deer muscle

The in vitro stability of cocaine in horse blood, sheep vitreous humour (VH) and homogenised deer muscle is described. The stability of cocaine in horse blood was of interest because many toxicology laboratories utilise horse blood for the preparation of calibration and check standards and the latter are typically stored during routine use. The storage stability of cocaine in human VH and muscle has not been previously reported. In the absence of blank human VH and muscle, cocaine stability under varying conditions was demonstrated in animal tissues. Blood and VH were stored with and without addition of NaF at room temperature (RT), 4°C and -18°C for 84 days. Muscle homogenates were prepared in water, water/2% NaF, and phosphate buffer (pH 6.0)/2% NaF, and stored for 31 days at RT, 4°C and -18°C. Cocaine stability in human muscle obtained from cocaine positive forensic cases was assessed following storage at -18°C for 13 months. Cocaine and benzoylecgonine (BZE) were extracted using SPE and quantified by GC-MS/MS. Cocaine was stable for 7 days in refrigerated (4°C) horse blood fortified with 1 and 2% NaF. In the absence of NaF, cocaine was not detectable by day 7 in blood stored at RT and 4°C and had declined by 81% following storage at -18°C. At 4°C the rate of cocaine degradation in blood preserved with 2% NaF was significantly slower than with 1% NaF. The stability of cocaine in horse blood appeared to be less than that reported for human blood, probably attributable to the presence of carboxylesterase in horse plasma. Cocaine stored in VH at -18°C was essentially stable for the study period whereas at 4°C concentrations decreased by >50% in preserved and unpreserved VH stored for longer than 14 days. Fluoride did not significantly affect cocaine stability in VH. The stability of cocaine in muscle tissue homogenates significantly exceeded that in blood and VH at every temperature. In preserved and unpreserved samples stored at 4°C and below, cocaine loss did not exceed 2%. The increased stability of cocaine in muscle was attributed to the low initial pH of post-mortem muscle. In tissue from one human case stored for 13 months at -18°C the muscle cocaine concentration declined by only 15% (range: 5-22%). These findings promote the use of human muscle as a toxicological specimen in which cocaine may be detected for longer compared with blood or VH.     

Evaluation of the Cozart RapiScan drug test system for opiates and cocaine in oral fluid

The purpose of this study was to evaluate the efficiency of the Cozart RapiScan (CRS) drug test system for detecting opiates and cocaine in oral fluid. Oral fluid samples were collected using the Cozart RapiScan collection system from 358 donors who were receiving treatment for their addiction and were monitored for drug misuse. A further 103 oral fluid samples were collected from volunteer donors who were not drug users. The samples were analyzed in the laboratory using the two-panel Cozart RapiScan cartridge for opiates and cocaine and confirmed using gas chromatography-mass spectrometry (GC-MS). The samples were stored frozen at -20 degrees C until analysis by GC-MS. The overall accuracy of the CRS for both opiates and cocaine was 100%. Samples spiked at 50% above and below the cut-off consistently gave negative and positive results respectively. A total of 88 samples were positive for various opiates and 111 samples were positive for cocaine and/or its metabolites. The CRS for opiates and cocaine in oral fluid, using a cut-off of 30 ng/mL morphine or benzoylecgonine equivalents in neat oral fluid, had overall efficiencies of 98% and 99%, respectively, versus GC-MS. A series of potential adulterants of oral fluid were evaluated and shown not to alter the outcome of the test result.     

Oral fluid testing for cannabis: on-site OraLine IV s.a.t. device versus GC/MS

Saliva or "oral fluid" has been presented as an alternative matrix to document drug use. The non-invasive collection of a saliva sample, which is relatively easy to perform and can be achieved under close supervision, is one of the most important benefits in a driving under the influence situation. Moreover, the presence of Delta9-tetrahydrocannabinol (THC) in oral fluid is a better indication of recent use than when 11-nor-Delta9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) is detected in urine, so there is a higher probability that the subject is experiencing pharmacological effects at the time of sampling. In the first part of the study, 27 drug addicts were tested for the presence of THC using the OraLine IV s.a.t. device to establish the potential of this new on-site DOA detection technique. In parallel, oral fluid was collected with the Intercept DOA Oral Specimen Collection device and tested for THC by gas chromatography mass spectrometry (GC/MS) after methylation for THC (limit of quantification: 1 ng/mL). The OraLine device correctly identified nine saliva specimens positive for cannabis with THC concentrations ranging from 3 to 265 ng/mL, but remained negative in four other samples where low THC concentrations were detected by GC/MS (1-13 ng/mL). One false positive was noted. Secondly, two male subjects were screened in saliva using the OraLine and Intercept devices after consumption of a single cannabis cigarette containing 25mg of THC. Saliva was first tested with the OraLine device and then collected with the Intercept device for GC/MS confirmation. In one subject, the OraLine on-site test was positive for THC for 2 h following drug intake with THC concentrations decreasing from 196 to 16 ng/mL, while the test remained positive for 1.5 h for the second subject (THC concentrations ranging from 199 to 11 ng/mL). These preliminary results obtained with the OraLine IV s.a.t. device indicate more encouraging data for the detection of THC using on-site tests than previous evaluations.     

Validated method for the simultaneous determination of Delta9-THC and Delta9-THC-COOH in oral fluid, urine and whole blood using solid-phase extraction and liquid chromatography-mass spectrometry with electrospray ionization

A fully validated, sensitive and specific method for the extraction and quantification of Delta(9)-tetrahydrocannabinol (THC) and 11-nor-9-carboxy-Delta(9)-THC (THC-COOH) and for the detection of 11-hydroxy-Delta(9)-THC (11-OH THC) in oral fluid, urine and whole blood is presented. Solid-phase extraction and liquid chromatography-mass spectrometry (LC-MS) technique were used, with electrospray ionization. Three ions were monitored for THC and THC-COOH and two for 11-OH THC. The compounds were quantified by selected ion recording of m/z 315.31, 329.18 and 343.16 for THC, 11-OH THC and THC-COOH, respectively, and m/z 318.27 and 346.26 for the deuterated internal standards, THC-d(3) and THC-COOH-d(3), respectively. The method proved to be precise for THC and THC-COOH both in terms of intra-day and inter-day analysis, with intra-day coefficients of variation (CV) less than 6.3, 6.6 and 6.5% for THC in saliva, urine and blood, respectively, and 6.8 and 7.7% for THC-COOH in urine and blood, respectively. Day-to-day CVs were less than 3.5, 4.9 and 11.3% for THC in saliva, urine and blood, respectively, and 6.2 and 6.4% for THC-COOH in urine and blood, respectively. Limits of detection (LOD) were 2 ng/mL for THC in oral fluid and 0.5 ng/mL for THC and THC-COOH and 20 ng/mL for 11-OH THC, in urine and blood. Calibration curves showed a linear relationship for THC and THC-COOH in all samples (r(2)>0.999) within the range investigated. The procedure presented here has high specificity, selectivity and sensitivity. It can be regarded as an alternative method to GC-MS for the confirmation of positive immunoassay test results, and can be used as a suitable analytical tool for the quantification of THC and THC-COOH in oral fluid, urine and/or blood samples.     

Correlation of Delta9-tetrahydrocannabinol concentrations determined by LC-MS-MS in oral fluid and plasma from impaired drivers and evaluation of the on-site Dräger DrugTest

Oral fluid (collected with the Intercept((R)) device) and plasma samples were obtained from 139 individuals suspected of driving under the influence of drugs and analyzed for Delta(9)-tetrahydrocannabinol (THC), the major psychoactive constituent of cannabis, using a validated quantitative LC-MS-MS method. The first aim of the study was to investigate the correlation between the analytical data obtained in the plasma and oral fluid samples, to evaluate the use of oral fluid as a 'predictor' of actual cannabis influence. The results of the study indicated a good accuracy when comparing THC detection in oral fluid and plasma (84.9-95.7% depending on the cut-off used for plasma analysis). ROC curve analysis was subsequently used to determine the optimal cut-off value for THC in oral fluid with plasma as reference sample, in order to 'predict' a positive plasma result for THC. When using the LOQ of the method for plasma (0.5 ng/mL), the optimal cut-off was 1.2 ng/mL THC in oral fluid (sensitivity, 94.7%; specificity, 92.0%). When using the legal cut-off in Belgium for driving under the influence in plasma (2 ng/mL), an optimal cut-off value of 5.2 ng/mL THC in oral fluid (sensitivity, 91.6%; specificity, 88.6%) was observed. In the second part of the study, the performance of the on-site Dr?ger DrugTest for the screening of THC in oral fluid during roadside controls was assessed by comparison with the corresponding LC-MS-MS results in plasma and oral fluid. Since the accuracy was always less than 66%, we do not recommend this Dr?ger DrugTest system for the on-site screening of THC in oral fluid.     

The effect of storage at various temperatures on blood alcohol concentration

There is a paucity of data available on the effect of storage on blood alcohol concentration (BAC) at elevated temperatures. Changes in serum alcohol concentration (SAC) and BAC were studied. Serum samples spiked with alcohol in the presence or absence of preservative were stored at 26.7 °, 32.2 ° or 37.8 °C respectively. Serum alcohol concentrations were determined daily on days 1 through 14, and on days 21 and 35. Under these controlled conditions, no significant change in SAC was observed at the aforementioned temperatures. Whole blood samples submitted from outside agencies were initially analyzed (day 1), then stored for 35 days at different elevated temperatures before a second analysis. The average loss in BAC was 19.20 ± 15.6, 9.95 ± 5.7, and 15.60 ± 6.9% when the samples were stored at 26.7, 32.2 and 37.8 °C, respectively. The alcohol loss from whole blood samples may be attributed to chemical oxidation rather than to elevated temperatures. It is, therefore, concluded that a whole blood sample obtained from a living individual and stored in a locker, glove compartment or other environment where the temperature is elevated, may lose 10–19% of its alcohol content over 35 days of storage. On the other hand, when a serum or plasma sample is exposed to the same environment, no significant change in SAC was observed. The utility of this information is significant to the forensic toxicologist. The results of this study suggest that a whole blood sample analyzed after exposure to elevated temperature may have had, originally, a higher BAC.     

Performance characteristics of the Cozart RapiScan Oral Fluid Drug Testing System for opiates in comparison to ELISA and GC/MS following controlled codeine administration

Oral fluid is an interesting alternative matrix for drug testing in many environments, including law enforcement, workplace drug testing, and drug treatment facilities. Performance characteristics of the FDA-cleared, qualitative, Cozart RapiScan Opiate Oral Fluid Drug Testing System (Opiate Cozart RapiScan System or Opiate CRS) were compared to the semi-quantitative Cozart Microplate EIA Opiate Oral Fluid Kit (Opiate ELISA) and to gas chromatography/mass spectrometry (GC/MS). The following oral fluid opiate cutoffs were evaluated: the GC/MS limit of quantification (LOQ) of 2.5 mg/l; 15 microg/l currently used for oral fluid testing in the United Kingdom (UK); 30 microg/l (Opiate CRS cutoff); and 40 microg/l, the proposed Substance Abuse and Mental Health Services Administration (SAMHSA) cutoff. Subjects provided informed consent to participate in this IRB-approved research and resided on the closed research ward throughout the study. Three oral codeine doses of 60 mg/70 kg were administered over a 7-day period. After a 3-week break, subjects received three doses of 120 mg/70 kg within 7 days. Oral fluid specimens (N = 1273) were analyzed for codeine (COD), norcodeine (NCOD), morphine (MOR) and normorphine (NMOR) by GC/MS with an LOQ of 2.5 microg/l for all analytes. MOR and NMOR were not detected in any sample; 26.5% of the specimens were positive for COD and 13.7% for NCOD. Opiate CRS uses a preset, qualitative cutoff of 10 microg/l; this is equivalent to 30 microg/l in undiluted oral fluid as the oral fluid collection process involves a 1:3 dilution with buffer. Sensitivity, specificity, and efficiency of Opiate CRS compared to Opiate ELISA were 98.6, 98.1, and 98.2% at a 30 microg/l cutoff and 99.0, 96.2, and 96.6% at a 40 microg/l cutoff. Compared to the much lower GC/MS LOQ of 2.5 microg/l, sensitivity, specificity and efficiency were 66.8, 99.3 and 90.7%. Increasing the GC/MS cutoff to the current UK level yielded performance characteristics of 81.5% (sensitivity), 99.3% (specificity), and 95.4% (efficiency). Using a GC/MS cutoff identical to the preset Opiate CRS cutoff yielded sensitivity, specificity, and efficiency of 88.5, 99.2, and 97.5%, respectively. At the proposed SAMSHA confirmation cutoff of 40 microg/l, sensitivity increased with little change in specificity and efficiency (91.3% sensitivity, 98.9% specificity, and 97.5% efficiency). Oral fluid is a suitable matrix for detecting drugs of abuse. Opiate CRS, with a 30 microg/l cutoff, is sufficiently sensitive, specific and efficient for oral fluid opiate analysis, performing similarly to Opiate ELISA at the same cutoff, and having performance characteristics >91% when compared to GC/MS at the proposed SAMHSA cutoff.     

Drugs in oral fluid in randomly selected drivers

There were 13,176 roadside drug tests performed in the first year of the random drug-testing program conducted in the state of Victoria. Drugs targeted in the testing were methamphetamines and Δ⁹-tetrahydrocannabinol (THC). On-site screening was conducted by the police using DrugWipe^®, while the driver was still in the vehicle and if positive, a second test on collected oral fluid, using the Rapiscan^®, was performed in a specially outfitted “drug bus” located adjacent to the testing area. Oral fluid on presumptive positive cases was sent to the laboratory for confirmation with limits of quantification of 5, 5, and 2 ng/mL for methamphetamine (MA), methylenedioxy-methamphetamine (MDMA), and THC, respectively. Recovery experiments conducted in the laboratory showed quantitative recovery of analytes from the collector. When oral fluid could not be collected, blood was taken from the driver and sent to the laboratory for confirmation. These roadside tests gave 313 positive cases following GC–MS confirmation. These comprised 269, 118, and 87 cases positive to MA, MDMA, and THC, respectively. The median oral concentrations (undiluted) of MA, MDMA, and THC was 1136, 2724, and 81 ng/mL. The overall drug positive rate was 2.4% of the screened population. This rate was highest in drivers of cars (2.8%). The average age of drivers detected with a positive drug reading was 28 years. Large vehicle (trucks over 4.5 t) drivers were older; on average at 38 years. Females accounted for 19% of all positives, although none of the positive truck drivers were female. There was one false positive to cannabis when the results of both on-site devices were considered and four to methamphetamines.     

Evaluation of the Cozart RapiScan drug test system for opiates and cocaine in oral fluid

The purpose of this study was to evaluate the efficiency of the Cozart^® RapiScan (CRS) drug test system for detecting opiates and cocaine in oral fluid. Oral fluid samples were collected using the Cozart^® RapiScan collection system from 358 donors who were receiving treatment for their addiction and were monitored for drug misuse. A further 103 oral fluid samples were collected from volunteer donors who were not drug users. The samples were analyzed in the laboratory using the two-panel Cozart^® RapiScan cartridge for opiates and cocaine and confirmed using gas chromatography–mass spectrometry (GC–MS). The samples were stored frozen at −20 °C until analysis by GC–MS. The overall accuracy of the CRS for both opiates and cocaine was 100%. Samples spiked at 50% above and below the cut-off consistently gave negative and positive results respectively. A total of 88 samples were positive for various opiates and 111 samples were positive for cocaine and/or its metabolites. The CRS for opiates and cocaine in oral fluid, using a cut-off of 30 ng/mL morphine or benzoylecgonine equivalents in neat oral fluid, had overall efficiencies of 98% and 99%, respectively, versus GC–MS. A series of potential adulterants of oral fluid were evaluated and shown not to alter the outcome of the test result.     

Optimization of extraction parameters for the chemical profiling of 3,4-methylenedioxymethamphetamine (MDMA) tablets

The extraction of impurities from illegally produced 3,4-methylenedioxymethamphetamine (MDMA) has been studied in order to optimize the parameters. Two different MDMA samples were used. Particular attention was paid to the influence of the pH, the evaporation step, and the sample storage. The method used was an extraction of impurities by diethyl ether from a buffer solution at pH 11.5, followed by gas chromatography (GC) mass spectrometric (MS) analyses after a dryness concentration under monitored conditions of the ethereal extract. Repeat extractions of the same sample gave an average relative standard deviation (RSD) of less than 8.5% within day and less than 10.5% between days.     

Determination of MDMA, MDA, MDEA and MBDB in oral fluid using high performance liquid chromatography with native fluorescence detection

This paper describes the analytical methodology for the determination of MDMA, MDA, MDEA and MBDB in oral fluid. After a liquid–liquid extraction, the analysis was carried out by high performance liquid chromatography (HPLC), with fluorescence detection. The detector wavelength was fixed at 285 nm for excitation and 320 nm for emission. The mobile phase, a mixture of phosphate buffer (pH = 5) and acetonitrile (75:25), and the column, Kromasil 100 C8 5 μm 250 mm × 4.6 mm, allowed good separation of the compounds in an isocratic mode in only 10 min. The method was validated and showed good limits of detection (2 ng/mL) and quantitation (10 ng/mL) for all the amphetamine derivatives. No interfering substances were detected. A stability study of these compounds in oral fluid stored at three different temperatures (−18, 4 and 20 °C) over 10 weeks was conducted, showing a time-dependent degradation of the four compounds.