Comparison of daily urine, sweat, and skin swabs among cocaine users.

This study (1) compares urine, skin swabs, and PharmChek sweat patches for monitoring drug use; (2) measures possible environmental contamination in recent cocaine (COC) users; and (3) evaluates various immunoassays (IA) for screening COC in diverse matrices. Unique aspects include daily urine monitoring of 10 participants for 4 weeks, multiple monitoring methods, analysis for all specimens by IA and gas chromatography (GC)/mass spectrometry (MS), and the potential for continued illicit drug use by participants. Urine served as the "gold standard" specimen for determining drug use. Only cocaine and related substances were detected. Trace amounts of drugs were found on the skin (<50 ng per swab) of urine-negative participants' hands or forehead. In contrast, larger quantities of COC were found on the skin of individuals with BE-positive urines or individuals living with drug users (up to 20 microg per swab). Patch COC amounts among the three regular users (250-9000, 0-240, 160-22,000 ng per patch) exceeded BE (50-950, none, 30-2200 ng per patch). Pre-swabs, valuable for interpreting the source or time frame of positive patch results, contained substantial COC (38-1160, 0-152, 34-762 ng per swab) prior to patch application; therefore, patch results may represent current use, prior use, contamination, or a combination. In three individuals with no indication of cocaine use, false positives (defined as sweat patch positive when urine specimens were <300ng BE/ml) occurred at a 7% rate. Proposed cut-off concentrations of 75 ng cocaine per patch and 300 ng BE/ml urine curtail the incidence of false positives in this limited population. Three immunoassays were compared to screen specimens for cocaine: a modified, manual Microgenics CEDIA; a Cozart ELISA; and an OraSure ELISA. CEDIA's limit of detection (LOD) was 81ng/ml, compared with LODs of 4 ng/ml for the Cozart ELISA and 1.5 ng/ml for the OraSure ELISA. Cozart correlated with OraSure results for COC concentrations <2000 ng per swab (n=117), r(2)=0.79.

Susceptibility of PharmChek drugs of abuse patch to environmental contamination.

The key component of the PharmChek sweat patch, the membrane, has been tested for the passage of externally applied materials. Drugs in the uncharged state rapidly penetrated the membrane but charged species were greatly slowed. In basic media, detectable concentrations of cocaine, methamphetamine, and heroin were observed at the earliest collection time (ca. 30 s), after drugs were placed on the outside of the membrane. Drug concentrations increased over the 2 h time course, when amounts detected (1710 ng cocaine, 1060 ng methamphetamine, 550 ng heroin per pad at 2 h) represented 5-17% of the drug deposited on the surface of the sweat patch. Drugs externally applied to human skin were shown to bind readily. Drugs deposited on the skin of drug-free volunteers several days prior to application of the sweat patch were not completely removed by normal hygiene or the cleaning procedures recommended before application of the sweat patch. Even 6 days of normal hygiene did not remove all drugs from externally contaminated skin and positive sweat patches resulted. A mechanism for passage of drugs through the sweat patch membrane, a mechanism for retention of drugs on skin, and a redesign of the sweat patch and modification of its use to reduce external contamination are proposed. Appropriate care should be taken in the interpretation of positive results from a sweat patch test until more research is conducted.

Chromatographic and electrophoretic approaches in ink analysis.

Inks are manufactured from a wide variety of substances that exhibit very different chemical behaviors. Inks designed for use in different writing instruments or printing methods have quite dissimilar components. Since the 1950s chromatographic and electrophoretic methods have played important roles in the analysis of inks, where compositional information may have bearing on the investigation of counterfeiting, fraud, forgery, and other crimes. Techniques such as paper chromatography and electrophoresis, thin-layer chromatography, high-performance liquid chromatography, gas chromatography, gel electrophoresis, and the relatively new technique of capillary electrophoresis have all been explored as possible avenues for the separation of components of inks. This paper reviews the components of different types of inks and applications of the above separation methods are reviewed.

Determination of illicit and/or abused drugs and compounds of forensic interest in biosamples by capillary electrophoretic/electrokinetic methods.

The application of capillary electrophoresis (CE) methods in forensic toxicology for the determination of illicit and/or misused drugs in biological samples is reviewed in the present paper. Sample pretreatments and direct injection modes used in CE for analysis of drugs in biological fluids are briefly described. Besides, applications of separation methods based on capillary zone electrophoresis or micellar electrokinetic chromatography with UV absorbance detection to (i) analysis of drugs of abuse, (ii) analysis of other drugs and toxicants of potential forensic interest and (iii) for metabolism studies are reviewed. Also, alternative CE methods are briefly discussed, including capillary isotachophoresis and separation on mixed polymer networks. High sensitivity detection methods used for forensic drug analysis in biological samples are then presented, particularly those based on laser induced fluorescence. A glimpse of the first examples of application of CE-mass spectrometry in forensic toxicology is finally given.

Death from heroin overdose: findings from hair analysis.

BACKGROUND: Morphine analysis of hair is used in forensic toxicology to study the addiction history of heroin addicts. To clarify the features underlying fatal heroin intake, we measured hair morphine content in a group of deceased heroin addicts, to verify a possible correlation between fatal heroin overdoses and the addiction behaviour of these individuals before death. METHODS: 91 deaths were attributed to heroin overdose in Verona, Italy, in 1993-96. We analysed the hair of 37 of these individuals, and of 37 active heroin addicts, 37 former heroin users abstinent from the drug for several months, and 20 individuals with no evidence of exposure to opioids. From each individual, a hair sample of about 150 mg was analysed by RIA and high-performance liquid chromatography, to measure the morphine content. FINDINGS: The mean morphine content in the hair of the addicts who had died was 1.15 ng/mg (SD 2.35 ng/mg; range 0-12.25 ng/mg) compared with 6.07 ng/mg (4.29; 1.15-17.0) in the active heroin addicts, 0.74 ng/mg (0.93; 0.10-3.32) in the abstinent former addicts, and values below the detection limit in the non-exposed group. Hair morphine content among those who had died was significantly lower than that in active heroin consumers (p<.00001), but not significantly different from that in the former addicts (p=0.978). INTERPRETATION: Although our findings may be subject to selection bias, since suitable hair samples were available for only 37 of the 91 addicts who had died, these findings support the theory of high susceptibility to opioid overdose after periods of intentional or unintentional abstinence, due to loss of tolerance. Medical staff running detoxification programmes should be aware of the risk inherent in relapse to heroin after a period of abstinence. Moreover, occasional heroin use without a build-up of tolerance could also give a high risk of overdose.

Frequency of pubic hair transfer during sexual intercourse.

This study measured the frequency of pubic hair transfer between a limited number of consenting heterosexual partners. The results derive from controlled experiments with a number of human subjects rather than forensic casework. Standardized collection procedures were observed, situational variables were tracked. Participants (forensic laboratory employees and their spouses) were six Caucasian couples who collected their pubic hair combings immediately following intercourse. Subjects provided informed consent in accordance with the protocol for human subjects approved by the U.A.B. institutional review board. The experiment was replicated ten times for five couples, and five times for another couple (total n = 110). Transfer frequencies were calculated from instances where foreign (exogenous) hairs were observed. Results showed at least one exogenous pubic hair in 17.3% (19/110) of combings. Transfers to males (23.6%, or 13/55) were more prevalent than transfers to females (10.9%, or 6/55). Only once were transfers observed simultaneously between both male and female. A total of 28 exogenous pubic hairs were identified. Subjects reported intercourse duration of 2-25 min, intervening intervals of 1-240 h, pre-coital bathing intervals of 0.25-24 h, and predominantly missionary position (76%). No clear relationship among these other survey variables was observed. The prevalence of female-to-male pubic hair transfers suggests the importance of collecting pubic hair combings from the male suspects as well as from female victims, provided the time interval is not extreme. Even under these optimum collection conditions, pubic hair transfers were observed only 17.3% of the time.

Simultaneous chiral separation of 3,4-methylenedioxymethamphet- amine, 3-4-methylenedioxyamphetamine, 3,4-methylenedioxyethylam- phetamine, ephedrine, amphetamine and methamphetamine by capillary electrophoresis in uncoated and coated capillaries with native beta-cyclodextrin as the chiral selector: preliminary application to the analysis of urine and hair.

The importance of the chiral analysis of amphetamine-related substances in both clandestine preparations and biological samples is widely recognized. For this purpose, capillary electrophoresis was successfully applied by several authors, but only few reports concerned ring-substituted amphetamines, which represent the main components of "ecstasy", a widely abused "recreational" substance. In the present work, the simultaneous chiral analysis of ephedrine, amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA), 3-4-methylenedioxyamphetamine (MDA) and 3,4-methalenedioxyethylamphetamine (MDE) is reported, by using capillary electrophoresis with native beta-cyclodextrin (15 mM) as the chiral selector. After preliminary tests at different pH values (phosphate buffer 100 mM, pH 2.5-9.0) and with bare or coated fused-silica capillaries, the optimized conditions were: pH 2.5 phosphate, uncoated capillary (45 cm x 50 microm inner diameter), potential 10 kV. Detection was either by fixed wavelength (200 nm) or multiwavelength (190-400 nm) UV absorbance. Under these conditions, good resolution was obtained for all the analytes, with excellent chiral selectivity and efficiency. The sensitivity for the individual enantiomers was better than 0.2 microg/mL, analytical precision was characterized by relative standard deviation values < 0.8% (< or = 0.15% with internal standardization) for migration times intra-day and < 2.0% (< or = 0.54% with internal standardization) day-to-day; linearity, in the range 0.156-40 microg/mL, and accuracy were also satisfactory. After a simple liquid-liquid extraction, urine samples could be analyzed with a sensitivity well below the recommended NIDA cut-off of 500 ng/mL. For hair samples, it was necessary to increase the sensitivity by applying a field-amplified sample stacking procedure, which allowed the chiral determination of MDA, MDMA and MDE at concentrations occurring in real samples from ecstasy users, with the possibility of recording UV spectra of the peaks.

Optimization of a simple method for the chiral separation of phenethylamines of forensic interest based on cyclodextrin complexation capillary electrophoresis and its preliminary application to the analysis of human urine and hair.

Because of the forensic importance of the chiral analysis of amphetamine and other phenethylamines for investigating their synthetic pathways and the metabolic patterns of these compounds, a capillary electrophoresis method has been developed based on the chiral selectivity of beta-cyclodextrin. The influence of different experimental conditions, such as cyclodextrin nature and concentration, voltage, temperature and buffer concentration and pH, on analytical performance has been studied. The optimized analytical conditions are: capillary: bare fused silica, 50 microns I.D., 40 cm effective length; buffer: 150 mM phosphate pH = 2.5, 15 mM beta-cyclodextrin; voltage: 10 kV; temperature: 17.5 degrees C; detection: UV absorption at 200 nm wavelength. Under these conditions, amphetamine, methamphetamine and ephedrine have been easily separated, with baseline resolution of the respective enantiomers. Sensitivity was better than 300 ng per ml. The average precision of migration times of the three analytes was good with RSD = 0.45% and 0.58% in intra-day and day-to-day tests, respectively. Reproducibility of peak heights was also good, with RSD = 2.51% and 3.14% in intra-day and day-to-day tests, respectively. The preliminary analysis of amphetamine in human urine and hair samples, subjected to a simple work-up procedure based on liquid-liquid extraction, showed clean blank electropherograms, excellent chiral resolution and sensitivity, suitable for the analysis of real samples from amphetamine users.

Hair analysis, a novel tool in forensic and biomedical sciences: new chromatographic and electrophoretic/electrokinetic analytical strategies.

Hair analysis for abused drugs is recognized as a powerful tool to investigate exposure of subjects to these substances. In fact, drugs permeate the hair matrix at the root level and above. Evidence of their presence remains incorporated into the hair stalk for the entire life of this structure. Most abusive drugs (e.g. opiates, cocaine, amphetamines, cannabinoids etc.) and several therapeutic drugs (e.g. antibiotics, theophylline, beta 2-agonists, etc.) have been demonstrated to be detectable in the hair of chronic users. Hence, hair analysis has been proposed to investigate drug abuses for epidemiological, clinical, administrative and forensic purposes, such as in questions of drug-related fatalities and revocation of driving licences, alleged drug addiction or drug abstinence in criminal or civil cases and for the follow-up of detoxication treatments. However, analytical and interpretative problems still remain and these limit the acceptance of this methodology, especially when the results from hair analysis represent a single piece of evidence and can not be supported by concurrent data. The present paper presents an updated review (with 102 references) of the modern techniques for hair analysis, including screening methods (e.g. immunoassays) and more sophisticated methodologies adopted for results confirmation and/or for research purposes, with special emphasis on gas chromatography-mass spectrometry, liquid chromatography and capillary electrophoresis.

Cocaine detection in a university population by hair analysis and skin swab testing.

The ability to detect cocaine use/exposure by either hair or sweat analysis was compared in a random population of adults at a major US university. Sweat was obtained by wiping the forehead with a cosmetic puff containing isopropanol. Using cut-off levels for sweat of 2.2 ng cocaine/wipe and of hair of 0.05 ng cocaine/mg hair, sweat detected two times more cocaine use/exposure than did hair. Sweat analysis detected a use rate of 12% compared to a 6% rate by hair analysis, both greater than the 2% that would be expected in this population. The high rate of detection was surprising and suggests that use of, if not exposure to, cocaine is underreported. Controlled experiments showed that cocaine could remain on the skin for about 3 days after external exposure. At the current state of knowledge, sweat appears to measure both use and exposure. Nevertheless, sweat testing could be used in several scenarios (such as roadside driving while intoxicated) where the case of collection and testing of sweat could outweigh the passive exposure considerations. Cocaine concentrations in skin swabs > 15 ng/swab would appear to indicate recent use/exposure.

Assessment of an automated immunoassay based on kinetic interaction of microparticles in solution for determination of opiates and cocaine metabolite in urine.

A recently introduced automated immunoassay which is based on kinetic interaction of microparticles in solution (Roche ONLINE), was evaluated for the detection of cocaine metabolite benzoylecgonine (BE) and opiates in human urine. Cross-reactivity for the opiates morphine (100%), codeine (88%), 6-monoacetylmorphine (88%), and morphine 3-glucuronide (72%) was assessed. Analytical recovery evaluated on blank urines spiked with 0, 250, 300, 350, and 500 micrograms/L of morphine and BE (n = 10), varied from 85.2 to 100.2% for opiates and from 81.4 to 93.1% for the cocaine metabolite. The within-day precision ranged from 1.4 to 4.7% for morphine and from 4.2 to 4.8% for BE. The repeatability of the standards over 1 month was 1.0-3.3% for opiates and 1.7-5.1% for BE, and thus allowing measurements to continue over 30 days without re-calibration. This method compared favourably with the SYVA EMIT d.a.u system and gas chromatography/mass spectroscopy (GC/MS) methods.

Cocaine in hair, saliva, skin swabs, and urine of cocaine users' children.

The concentrations of cocaine and benzoylecgonine (BE) in the hair, saliva, skin secretions, and urine samples of cocaine-using mothers, their children, and other adults living in the same environment were compared. Subjects were screened from urban cocaine dependence treatment patients. Drug using adults had mean hair concentrations of 2.4 ng cocaine/mg hair (range = 0-12.2, sigma = 3.1, 15/16 positive) and 0.39 ng BE/mg hair (range = 0-1.9, sigma = 0.62), compared with children's mean hair concentrations of 2.4 ng cocaine/mg of hair (range = 0-14.4, sigma = 3.8, 22/24 positive) and 0.74 ng benzoylecgonine/mg hair (range = 0-5.4 sigma = 1.3). None of the children's urine specimens (0/22) were positive above 300 ng BE/ml. In contrast, 3/16 adult urine specimens were positive, even though they were enrolled in drug treatment. Saliva had detectable levels of BE for only one child (1/17) and one adult (1/17). Forehead swabs contained measurable quantities of cocaine for most children (19/26) and adults (15/17) and BE for children (7/26) and adults (7/17). Unlike urine results, overall hair cocaine concentrations for adults paralleled those of children and a clear cut-off concentration could not be established to differentiate these two groups.

High-performance liquid chromatographic determination of levodropropizine in human plasma with fluorometric detection.

The present paper describes a new high-performance liquid chromatographic method with fluorescence detection for the analysis of levodropropizine [S-(-)-3-(4-phenylpiperazin-1-yl)-propane-1,2-diol] (Levotuss), an anti-tussive drug, in human serum and plasma. A reversed-phase separation of levodropropizine was coupled with detection of the native fluorescence of the molecule, using excitation and emission wavelengths of 240 nm and 350 nm respectively. The analytical column was packed with spherical 5 microns poly(styrene-divinylbenzene) particles and the mobile phase was 0.1 M NaH2PO4 pH 3-methanol (70:30, v/v), containing 0.5% (v/v) tetrahydrofuran. For quantitation, p-methoxylevodropropizine was used as the internal standard. Samples of 200 microliters of either serum or plasma were mixed with 200 microliters of 0.1 M Na2HPO4 pH 8.9 and extracted with 5 ml of chloroform-2-propanol (9:1, v/v). The dried residue from the organic extract was redissolved with distilled water and directly injected into the chromatograph. The limit of detection for levodropropizine, in biological matrix, was about 1-2 ng/ml, at a signal-to-noise ratio of 3. The linearity was satisfactory over a range of concentrations from 3 to 1000 ng/ml (r2 = 0.99910); within-day precision tested in the range 5-100 ng/ml as well as day-to-day reproducibility proved acceptable, with relative standard deviations better than 1% in most cases. Interferences from as many as 91 therapeutic or illicit drugs were excluded.

Complementary use of capillary zone electrophoresis and micellar electrokinetic capillary chromatography for mutual confirmation of results in forensic drug analysis.

The purpose of this work was to compare different CE separation modes namely capillary zone electrophoresis (CZE) and micellar electrokinetic capillary chromatography (MECC) for the analysis of drugs of forensic interest in order to assess the mutual degree of independence and consequently the possibility of complementary use for mutual confirmation of results. A panel of drugs including caffeine, morphine, barbital, pentobarbital, codeine, nalorphine, lidocaine, procaine, heroin, flunitrazepam, acetylcodeine, papaverine, amphetamine, narcotine, cocaine, diazepam, tetracaine, narceine, 6-monoacetylmorphine acetylcodeine and thebaine, were separated according to a MECC and two CZE methods. The MECC separation was carried out in a bare silica capillary (50 micron I.D.) with a buffer composed of 25 mM borate (pH 9.24)--20% methanol--100 mM sodium dodecyl sulphate; the applied voltage was 20 kV. The first CZE method (CZE1) was carried out in 50 mM phosphate buffer (pH 2.35) at 20 kV with a bare silica capillary (50 micron I.D.), and the second (CZE2) with 50 mM borate (pH 9.24) at 12 kV with the same capillary. The three methods were effective in the separation of the test drug mixture, but MECC was the only able to resolve all the components. Relative (to flunitrazepam), migration time RSDs ranged from 0.3 to 2.8% for the three methods were compared with Spearman's test and with principal component analysis, CZE1 and CZE2 were significantly and directly correlated (r = 0.749, p < 0.002), whereas MECC and CZE2 were also significantly, but inversely correlated (r = -0.865, p < 0.001). MECC and CZE1 (limitedly to the basic drugs) appeared non-correlated (r= -0.131, p = 0.630) and therefore the two techniques are suitable for combined use to increase the discriminatory power.

Capillary electrophoresis: principles and applications in illicit drug analysis.

Capillary electrophoresis, which appeared in the early 1980s, is now rapidly expanding into many scientific disciplines, including analytical chemistry, biotechnology and biomedical and pharmaceutical sciences. In capillary electrophoresis,electrokinetic separations are carried out in tiny capillaries at high voltages (10-30 kV), thus obtaining high efficiencies (N > 10(5)) and excellent mass sensitivities (down to 10(-18)-10(-20) moles). The main features of capillary electrophoresis are: versatility of application (from inorganic ions to large DNA fragments), use of different separation modes with different selectivity, extremely low demands on sample volume, negligible running costs, possibility of interfacing with different detection systems, ruggedness and simplicity of instrumentation. Capillary electrophoresis applications in forensic sciences have appeared only recently, but are now rapidly growing, particularly in forensic toxicology. The present paper briefly describes the basic principles of capillary electrophoresis, from both the instrumental and analytical points of view. Furthermore, the main applications in the analysis of illicit/controlled drugs in both illicit preparations and biological samples are presented and discussed (43 references). It is concluded that the particular separation mechanism and the high complementarity of this technique to chromatography makes capillary electrophoresis a new powerful tool of investigation in the hands of forensic toxicologists.

Archival correspondence regarding the origin of the Harvey Cushing Society: the American Association of Neurological Surgeons.

Behind the scenes in the origin of the Harvey Cushing Society, now known as the American Association of Neurological Surgeons, there were many interesting political factors occurring, which appeared in correspondence and were preserved and later forwarded by William P. Van Wagenen to the Harvey Cushing Section of the Yale Medical Library. This correspondence, circa 1931, provides an interesting account of the aspirations of young neurosurgeons who wished to gain societal status, without offending the giants of the Society of Neurological Surgeons.