Screening and confirmation of drugs in urine: interference of hordenine with the immunoassays and thin layer chromatography methods

Doping detection in animals: A review of analytical methodologies published from 1990 to 2019

Despite the impressive innate physical abilities of horses, camels, greyhounds, or pigeons, doping agents might be administered to these animals to improve their performance. To control these illegal practices, anti-doping analytical methodologies have been developed. This review compiles the analytical methods that have been published for the detection of prohibited substances administered to animals involved in sports over 30 years. Relevant papers meeting the search criteria that discussed analytical methods aiming to detect and/or quantify doping substances in animal biological matrices published from 1990 to 2019 were considered. A total of 317 studies were included, of which 298 were related to horses, demonstrating significant advances toward the development of doping detection methods for equine sports. However, analytical methods for the detection of doping agents in sports involving other species are lacking. Due to enhanced accuracy and specificity, chromatographic analysis coupled to mass spectrometry detection is preferred over immunoassays. Regarding biological matrices, blood and urine remain the first choice, although alternative biological matrices, such as hair and feces, have been considered. With the increasing number and type of drugs used as doping agents, the analytes addressed in the published papers are diverse. It is very important to continue to detect and quantify these drugs, recognizing those that are most frequently used, in order to punish the abusers, protect animals' health, and ensure a healthier and genuine competition.

Theoretical and experimental proof for selective response of imprinted sorbent - analysis of hordenine in human urine

The objective of this paper was to extend comprehensive theoretical and experimental investigations at the molecular level to identify factors responsible for the high selectivity of imprinted sorbents. This knowledge was utilized in a new analytical strategy devoted to the analysis of hordenine in human urine after beer consumption. Among the various polymeric compositions tested, the most effective material was built up from methacrylic acid and ethylene glycol dimethacrylate (MIP1), showing a satisfactory binding capacity (4.44 ± 0.15 µmol g^-1) and high specificity towards hordenine (AF = 5.90). The comprehensive analyses of porosity data and surface measurements revealed differences between imprinted polymers. The characterization of binding sites of MIP1 revealed a heterogeneous population with two values of K_d (2.75 and 370 μmol L^-1) and two values of B_max (1.82 and 99 μmol g^-1) for higher and lower affinity respectively. The extensive theoretical analyses of interactions between various analytes and the MIP model cavity showed the highest binding energy for hordenine (ΔE_B1 = -175.17 kcal mol^-1). The method was validated for selectivity, lowest limit of quantification, calibration curve performance, precision, accuracy, matrix effect, carry-over and stability in urine. Extracts were prepared according to guidelines of the European Medicines Agency. The validation criteria were fulfilled, and the method was satisfactorily applied to urine samples collected prior to, and 2 h after, consumption of 2 L of beer, revealing the presence of hordenine at the mean level of 129 ± 27 ng mL^-1. Additionally, ability of the sorbent to purify the urine sample was assessed using flow injection analysis tandem mass spectrometry, for comparison with other extraction techniques.

Analysis of anonymous pooled urine from portable urinals in central London confirms the significant use of novel psychoactive substances

AIM

Analysis of urine samples collected across a city centre, for the detection of novel psychoactive substances (NPS).

DESIGN

Cross-sectional study of anonymized urine samples used for the analysis of classical recreational drugs, NPS and metabolites.

METHODS

Pooled urine samples collected from portable stand-alone four-person urinals across a city centre were analysed using full-scan accurate-mass high-resolution liquid chromatography coupled to tandem mass spectrometry. Data were processed against compound databases containing >1700 drug compounds and metabolites.

RESULTS

Seven established recreational drugs (3,4-methylenedioxyamphetamine, cocaine, cannabis, ketamine, 3,4-methylenedioxy-N-methylamphetamine, methamphetamine and amphetamine) and six potential NPS [hordenine (all 12 urinals), cathine (11), methylhexaneamine (9), 4-methylmethcathinone (6), methiopropamine and metabolites (2) and methoxetamine and metabolites (1)] were detected. Methylhexaneamine, methiopropamine and hordenine are currently uncontrolled in the UK, whereas methoxetamine is currently subject to a Temporary Class Drug Order. Metabolites of the anabolic steroid nandrolone were found in two urinals and trenbolone metabolites and clenbuterol in one urinal.

CONCLUSION

Analysis of pooled urine samples collected anonymously from stand-alone urinals in a large inner city can detect the use of recreational drugs, NPS and anabolic steroids. Metabolite detection indicates actual drug use, metabolism and elimination rather than simply discarded drugs in the urinals. This technique by confirming the actual drug(s) used has the potential to be additive to currently used datasets/key indicators providing more robust information for healthcare authorities, legislative and law enforcement on the drugs actually being used.

Hypothesis on interferences in kinetic interaction of microparticles in solution (KIMS) technology

The present paper describes an evaluation of the interferences found with an immunochemical drug test performed during a workplace control. During the period 1993–2003 more than 200,000 urine samples from workers were examined by the Italian Air Force. Samples were screened for drugs of abuse (opiates, cocaine, cannabinoids, amphetamines, methadone) using an immunochemical technique (Roche, kinetic interaction of microparticles in solution, KIMS). A total of 520 positive samples were sent to the Forensic Toxicology Laboratory for confirmation by gas chromatography/mass spectrometry (GC/MS). Approximately 39% of these were found to be true positives. For the remaining samples, pharmacological therapy in subjects was estimated to evaluate possible interferences due to medicine intake. Our study showed a high frequency of false-positive results with this immunochemical technique, mainly for the cannabinoid and amphetamine groups. Recurrent references to some medicines during subject anamnesis were noted.

Clin Chem Lab Med 2006;44;894–7.

Stereoselective determination of apomorphine enantiomers in serum with a cellulose-based high-performance liquid chromatographic chiral column using solid-phase extraction and ultraviolet detection

A novel and rapid method for the separation and determination of R-(-)- and S-(+)-enantiomers of apomorphine in serum by high-performance liquid chromatography with UV detection is reported. The method involved a solid-phase extraction of the R-(-)- and S-(+)-enantiomers of apomorphine and the internal standard R-(-)-propylnorapomorphine from serum using a C8 Bond-Elut column. The HPLC system consisted of a reversed-phase cellulose-based chiral column (Chiralcel OD-R, 250 x 4.6 mm I.D.) with a mobile phase of 35:65 (v/v) acetonitrile-0.05 M sodium perchlorate (pH 2.0, adjusted with 60-62% perchloric acid) at a flow-rate of 0.5 ml/min with UV detection at 273 nm. The detection and quantitation limits were 10 ng/ml for each enantiomer using 1 ml of serum. Linear calibration curves from 10 to 1000 ng/ml for both R-(-)- and S-(+)-enantiomers show coefficient of determination of more than 0.9995. Precision calculated as %R.S.D. and accuracy calculated as % error were 0.2-4.7 and 3.1-6.9%, respectively, for the R-(-)-enantiomer and 1.3-4.2 and 0.3-6.8%, respectively, for the S-(+)-enantiomer.

Bioluminescent assay for heroin and its metabolites

Illicit heroin is trafficked as a solid particulate drug, while heroin abuse is monitored by testing urine samples for its principal metabolites, morphine and morphine-3-glucuronide. Two novel bacterial enzymes were used in the development of a linked-enzyme assay for heroin and its metabolites: heroin esterase, which converts heroin to morphine, and morphine dehydrogenase, which oxidizes morphine to morphinone with the concomitant reduction of NADP+. A bioluminescent assay involving heroin esterase, morphine dehydrogenase, and the bacterial luciferase from Vibrio harveyi was developed and shown to be sensitive to 89 ng/mL heroin and 2.0 ng/mL morphine. Excellent correlation with the results from 83 authentic samples submitted for urine drug screening at a hospital laboratory was obtained. The bioluminescent assay exhibited greater specificity and speed than current immunological screening methods. A novel format of the bioluminescent assay involving immobilized enzymes was sensitive to 101 ng (250 pmol) of heroin and responded well to particulate heroin. This form of the test was sensitive enough to respond to one or two typical particles of illicit heroin.

Drug analysis for control purposes in forensic toxicology, workplace testing, sports medicine and related areas

This MiniReview describes the present guidelines for drug testing in forensic toxicology, workplace testing and doping control of athletes. Such guidelines are established to secure the chain of custody, from sample collection through analysis with screening, confirmation methods and interpretation, to the final report of results. Specifications for good laboratory practice, facility maintenance and quality assurance programs are described. The advantages and limitation of immunological drug assays and the necessity of specific chromatographic confirmation methods are discussed. The importance of correct interpretation of positive test results is illustrated. The effect of drug testing on the prevalence of drug abuse, accident rates and effectivity at the workplace is discussed.