Biomedical subjects

P Kintz

Publications and source records attributed to P Kintz.

At least 19 recordsLinked to original sources

PubMed1997

High-performance liquid chromatography-ionspray mass spectrometry for the specific determination of digoxin and some related cardiac glycosides in human plasma.

An original method based upon high-performance liquid chromatography coupled to ionspray mass spectrometry (HPLC-ISP-MS) has been developed for the identification and quantification in plasma of several cardiac glycosides, namely digoxin, digitoxin, lanatoside C and acetyldigitoxin. After single-step liquid-liquid extraction by chloroform-2-propanol (95:5, v/v) at pH 9.5 using oleandrin as an internal standard, solutes are separated on a 4 microm NovaPak C18 (Waters) column (150x2.0 mm, I.D.), using a gradient of acetonitrile-2 mM NH4COOH, pH 3 buffer (flow-rate 200 microl/min, post-column split 1:3). Detection is done by a Perkin-Elmer Sciex API-100 mass analyzer equipped with an ISP interface. In most instances the major ion observed is not [M+H]+ as expected, but [M+NH4]+. The mean retention times (min) are: lanatoside C, 5.74; digoxin, 6.00; digitoxin, 8.08, oleandrin, 8.30, acetyldigitoxin, 8.66 and 9.01 (isomers alpha and beta, respectively). The lower limits of detection in single ion monitoring mode range from 0.15 ng/ml (alpha- and beta-acetyldigitoxin) to 0.60 ng/ml (lanatoside C), making the method less sensitive than radioimmunoassay, whereas it is much more specific.

Acetyldigitoxins↗

PubMed1997

Interlaboratory comparison of quantitative determination of amphetamine and related compounds in hair samples.

Testing human hair for drugs of abuse is a relatively new technique which requires control before being fully accepted in justice applications. Laboratories must be able to demonstrate that they can accurately determine what drugs are present in unknown hair samples and at what levels. To date few exercises have been organized in USA, Germany and France, all devoted to opiates, cocaine and cannabis. However, the number of drugs which can be detected in hair is growing every day. Among them, amphetamine and related compounds, such as MDMA, are of major interest due to increasing abuse. At the initial state of this work, four different preparation procedures were used to test amphetamine, MDA and MDMA. Direct methanol extraction, acid (HCl 0.1 N), alkaline (NaOH 1 N) and enzymatic (beta-glucuronidase/arylsulfatase) hydrolyses were compared. Best recoveries were observed after alkaline hydrolysis. The same hair sample was powdered and sent to 16 laboratories, in USA (4), Germany (6), France (3), Spain (1), Japan (1) and Korea (1) to test amphetamine, methamphetamine, MDA and MDMA. All laboratories returned results within 3 months. Amphetamine tested positive 13 times with concentrations ranging from 3.3 to 17.5 ng/mg. Only 2 laboratories identified methamphetamine, using GC/MS, at low concentration (0.8 and 1.8 ng/mg), which appears to be a false positive. MDA and MDMA both tested positive in 14 cases, with concentrations ranging from 1.8 to 19.5, and 8.9 to 100.0 ng/mg for MDA and MDMA, respectively. These scattered results clearly indicated that new exercises are needed to ensure quality in hair testing. This is one of the major aims of the Society of Hair Testing.

3,4-Methylenedioxyamphetamine↗

PubMed1997

Testing human hair for flunitrazepam and 7-amino-flunitrazepam by GC/MS-NCI.

To validate information on flunitrazepam use, we investigated human hair for flunitrazepam and its major metabolite 7-amino-flunitrazepam by gas chromatography coupled to mass spectrometry in negative chemical ionization mode of detection. Samples were twice decontaminated with methylene chloride, pulverized in a ball mill and 50 mg of powdered hair were incubated in Soerensen buffer (pH 7.6) in the presence of diazepam-d5 used as internal standard. After liquid-liquid extraction of the incubation medium with diethylether-chloroform (80:20, by vol.), the organic phase was evaporated and the dry extract was derivatizated with heptafluorobutyric anhydride. Benzodiazepines were separated on a 30 m capillary column and detected using single ion monitoring. Among 40 hair samples tested (obtained from drug addicts deceased by heroin overdose), 14 were positive for both flunitrazepam and 7-amino-flunitrazepam and 12 for 7-amino-flunitrazepam only. Concentrations ranged from 31 to 129 pg/mg (mean: 60 pg/mg) and from 3 to 161 pg/mg (mean: 46 pg/mg) for flunitrazepam (14 cases) and 7-amino-flunitrazepam (26 cases), respectively. This first report described the detection of flunitrazepam and 7-amino-flunitrazepam in hair of chronic abusers. Due to the low concentrations observed, negative chemical ionization appears to be the alternative to test flunitrazepam and other benzodiazepines in hair.

Flunitrazepam↗

PubMed1997

Acute fatal poisoning with dichlorophen.

A case is presented involving an acute fatality resulting from self-administered dichlorophen, a chlorophenol fungicide. The compound was quantified using gas chromatography/mass spectrometry after extraction with methyl-tert-butyl ether, derivatization by methylation and separation on a HP5-MS capillary column. The blood concentration was 9.77 mg/l and other drugs, including ethanol, were not detected.

Dichlorophen↗

PubMed1997

Evidence of crack use by anhydroecgonine methylester identification.

A method using gas chromatography coupled to mass spectrometry for the determination of cocaine (COC) pyrolysis product, anhydroecgonine methylester (AEME), in plasma, saliva, urine, sweat and hair is described. The same procedure allows the simultaneous determination of COC, benzoylecgonine (BZE), ecgonine methylester (EME) and cocaethylene (CE). After suitable sample preparation (desorption of the sweat patch, acid hydrolysis of the hair) the target drugs were extracted using a 3-steps liquid-liquid extraction (pH 8.4) in presence of deuterated internal standards in chloroform-isopropanol-n-heptane (50 : 17 : 33, v/v). Derivatization was achieved using BSTFA+1% TMCS. Ions for AEME monitoring were m/z 82, 166, 152 and 181. Artifact formation from COC or EME of AEME during the injection was less than 0.5%. AEME was never detected in blood sample although the corresponding urine tested positive. Urine concentrations, in about 90 positive AEME samples, were in the range 5 to 1477 ng/ml. In one case of crack overdose, AEME in sweat was 53 ng/patch with a COC concentration of 1231 ng/patch. AEME in saliva ranged from 5 to 18 ng/ml in the same case. Finally, AEME was identified in 32 hair specimens of crack abusers including fetal hair, with concentrations in the range 0.20 to 21.56 ng/mg. These results suggest that AEME can be a useful marker for the detection of COC smoking in clinical and forensic cases.

Cocaine↗

PubMed1997

HPLC/MS determination of buprenorphine and norbuprenorphine in biological fluids and hair samples.

An original method, based upon HPLC (high performance liquid chromatography)/Ionspray-MS, has been developed for the identification of buprenorphine (BUP) and norbuprenorphine (norBUP) in biological fluids and hair samples. Biological fluids (2 mL) are extracted at pH 8.4 by CHCl3/2-propanol/n-heptane (25:10:65, v/v) after addition of deuterated BUP (BUP-d4, 10 ng). Hair samples (40 mg) are extracted in the same conditions after decontamination by CH2Cl2, mechanical pulverization, addition of BUP-d4 (1 ng), acidic incubation (1 mL 0.1 N HCl, 56 degrees C overnight), then neutralization by NaOH. Analytes are separated on a 4-microns NovaPak C18 (Waters) column (150 by 2.0 mm, ID) with a mobile phase of acetonitrile/2 mM NH4COOH buffer, pH 3.0 (80:20, v/v; flow rate 200 microL/min; post column split 1:3). Detection is done by a Perkin-Elmer Sciex API-100 mass analyzer equipped with an ISP interface (nebulizing and curtain gas:99.95-% N2; main settings: orifice + 50 V, electron multiplier + 2400 V). The mean retention times for BUP, BUP-d4, and norBUP are 5.84, 5.79, and 4.42 min, respectively. For all compounds, mass spectra exhibit a unique, protonated molecular ion [M + H]+ at m/z 414 (norBUP), 468 (BUP), and 472 (BUP-d4), without any significant fragmentation. The lower limits of detection are 0.10 and 0.05 ng/mL blood, and 4 and 2 pg/mg hair for BUP and norBUP, respectively. BUP and norBUP concentrations measured in hair from six addicts under substitutive therapy by BUP ranged from 4 to 140 pg/mg, and from nondetected to 67 pg/mg, respectively. The good performances of this method in terms of both sensitivity and specificity make it a convenient alternative to HPLC/coulometry and GC/MS for the separate analysis of BUP and norBUP in biological samples.

Adult↗

PubMed1997

Enantioselective separation of methadone and its main metabolite in human hair by liquid chromatography/ion spray-mass spectrometry.

Optical isomers exhibit significant differences in their affinities for receptor sites, biotransformation and binding to serum and tissue proteins. Methadone has been used for the substitution of heroin addicts since 1964. The racemic form is used, i.e., a mixture of the biologically active R-form and the practically inactive S-form. To investigate methadone distribution, a chiral separation of the isomers was developed in human hair samples. The method involves decontamination of hair with water and acetone, pulverization in a ball mill, enzymatic hydrolysis in presence of deuterated internal standards, solid-phase extraction, and liquid chromatography/ion spray-mass spectrometry. Enantioselective separation of methadone and its main metabolite, EDDP, was obtained using an alpha1-acid glycoprotein column (100 by 4 mm ID). In all nine specimens obtained from subjects under racemic methadone treatment in a detoxification center, R- and S-enantiomers of methadone and EDDP were identified with the following concentrations: 2.58-10.22, 1.89-9.53, 0.42-1.73, and 0.40-2.10 ng/mg for R-methadone, S-methadone, R-EDDP, and S-EDDP, respectively. Results are suggestive of a predominance of the Renantiomer of methadone in human hair.

Chromatography, Liquid↗

PubMed1997

[Chiral separation of seven beta-blockers in the French pharmacopoeia].

Determination of optical isomers is based on some molecule properties to have one or more chiral asymmetrical carbon center. Enantiomers can be resolved by high performance liquid chromatography (HPLC) with a chiral mobile phase additive, by change into diastereoisomers by derivatization or by separation on chiral column. We retained the last technique for the separation of seven beta-blockers (atenolol, alprenolol, labetalol, nadolol, oxprenolol, pindolol and propranolol) using an alpha 1-AGP column. Results indicate that the mobile phase was specific to each beta-blocker. The wavelength chosen was lambda = 225 nm and the flow rate was 0.9 ml/min. A part from that, determinations of isomers of propranolol and atenolol in different fluids biologicals were also achieved.

Adrenergic beta-Antagonists↗

PubMed1997

Sweat testing for heroin and metabolites in a heroin maintenance program.

Recent advances in sensitive analytical techniques have enabled the analysis of drugs in unconventional biological materials such as sweat. In a study conducted during a heroin maintenance program, 14 subjects had sweat patches applied, then received intravenously two or three doses of heroin hydrochloride ranging from 80 to 1000 mg/day. The sweat patch was applied 10 min before the first dosage and removed approximately 24 h later, minutes before the next dosage. Absorbent pads were stored at -20 degrees C in plastic tubes until analysis. The target drugs were extracted in 5 mL of acetonitrile in the presence of 100 ng each of heroin-d9, 6-acetylmorphine-d3, and morphine-d3. After agitation for 30 min, the acetonitrile solution was divided into two portions: 2 mL for heroin testing and the remainder for testing for the other compounds. After evaporation, the residue of the first portion was reconstituted in 35 microL of acetonitrile; the second was derivatized by silylation with 40 microL of N,O-bis(trimethylsilyl)trifluoroacetamide containing 10 mL/L trimethylchlorosilane. Drugs were analyzed by GC-MS in electron impact mode. Concentrations (nanograms per patch) ranged from 2.1 to 96.3 for heroin, 0 to 24.6 for 6-acetylmorphine, and 0 to 11.2 morphine. Except in one case, heroin was the major drug present in sweat, followed by 6-acetylmorphine and morphine. We observed no correlation between the doses of heroin administered and the concentrations of heroin measured in sweat.

Acetonitriles↗

PubMed1996

Simultaneous high-performance liquid chromatographic analysis of flunitrazepam and four metabolites in serum.

A high-performance liquid chromatographic method for the simultaneous determination of flunitrazepam and four metabolites, desmethylflunitrazepam (DMF), 7-aminodesmethylflunitrazepam (7-NH2DMF), 7-aminoflunitrazepam (7-NH2F) and 3-hydroxyflunitrazepam (3-OHF), in serum is described. The method involves a simple extraction from alkalinized plasma (pH 9.5) into diethyl ether-chloroform (80:20, v/v). Prazepam was used as an internal standard for the quantification of the five compounds. Separation was achieved with a 10 microns RSil CN column (300 x 3.9 mn I.D.). The detection wavelength was set at 242 nm. The limits of detection ranged from 2.5 to 5 micrograms/l with a limit of quantification of 10 micrograms/l for all analytes.

Anti-Anxiety Agents↗

PubMed1996

Headspace GC/MS testing for chlorodifluoromethane in two fatal cases.

Two cases of lethal poisoning due to chlorodifluoromethane (Freon 22) inhalation are described. The fluorocarbon was determined in biological tissues by headspace gas chromatography/mass spectrometry. Ions monitored were m/z 67, 86 and 51, the latter being used for quantification. Blood concentrations were 26.0 and 37.1 microliters/ml. In both cases, the drug was also identified in urine, vitreous humor and bile, but in much lower concentrations.

Accidents, Occupational↗

PubMed1996

Hair analysis for nordiazepam and oxazepam by gas chromatography--negative-ion chemical ionization mass spectrometry.

A procedure is presented for the identification of nordiazepam and its metabolite, oxazepam, in human hair. The method involves decontamination of hair with dichloromethane, incubation in phosphate buffer (pH 7.6) in the presence of deuterated internal standards, liquid-liquid extraction, derivatization with N,O-bis(trimethylsilyl)trifluoroacetamide plus 1% trimethylchlorosilane and gas chromatography-mass spectrometry using negative-ion chemical ionization with methane. Among thirty samples obtained from polydrug abusers, thirteen tested positive for nordiazepam, in the range of 0.25-18.87 ng/mg. Five samples were also positive for oxazepam, in the range 0.11-0.50 ng/mg.

Adult↗

PubMed1996

High-performance liquid chromatography coupled to ion spray mass spectrometry for the determination of colchicine at ppb levels in human biofluids.

An original method based upon high-performance liquid chromatography coupled to ion spray mass spectrometry (HPLC-ISP-MS) has been developed for the identification and quantification of colchicine (COL) in human blood, plasma or urine. After single-step liquid-liquid extraction by dichloromethane at pH 8.0 using tofisopam (TOF) as an internal standard, solutes are separated on a 5-microns C18 Microbore (Alltech) column (250 x 1.0 mm, I.D.), using acetonitrile-2 mM NH4COOH, pH 3 buffer (75: 25, v/v) as the mobile phase (flow-rate 50 microliters/min). Detection is done by a Perkin-Elmer Sciex API-100 mass analyzer equipped with a ISP interface (nebulizing and curtain gas: N2, quality U; main settings: ISP, +4.0 kV; OR, +50 V; Q0, -10 V; Q1, -13 V; electron multiplier, +2.2 kV); MS data are collected as either total ion current (TIC, m/z 100-500 or 380-405), or selected ion monitoring (SIM) at m/z 400 and 383 for COL and TOF, respectively. COL mass spectrum shows a prominent molecular ion [M + H]+ at m/z 400. Increasing OR potential fails to provide a significant fragmentation. Retention times are 2.70 and 4.53 min for COL and TOF, respectively. The quantification method shows a good linearity (r = 0.998) over a concentration range from 5 to 200 ng/ml. The lower limit of detection in SIM mode is 0.6 ng/ml COL, making the method convenient for both clinical and forensic purposes.

Anti-Anxiety Agents↗

PubMed1996

Trichloroethanol is not a metabolite of alpha chloralose.

Head space capillary gas chromatography was used to detect alpha chloralose and its potent metabolite, trichloroethanol in clinical and forensic cases. Although alpha chloralose was identified in blood and urine in all cases, trichloroethanol was never detected. In a fatal case the alpha chloralose concentration in blood was 151.3 mg/l. It was concluded that trichloroethanol is not a metabolite of alpha chloralose.

Adult↗

PubMed1996

Detection and quantification of lorazepam in human hair by GC-MS/NCI in a case of traffic accident.

A traffic accident caused by a man who declared that he was driving under influence of drugs (Temesta), led our laboratory to develop a procedure for the detection and the quantification of lorazepam in human hair. The method involves decontamination of hair with dichloromethane, incubation in Soerensen buffer (pH 7.6) in the presence of lorazepam-d4, liquid-liquid extraction with diethylether-chloroform (80:20, v/v) at pH 8.4, derivatization by silylation and detection by GC-MS/NCI. The increasing concentrations of lorazepam from the end to the roots of a 16-cm-long hair strand (i.e. 31 pg/mg, 40 pg/mg and 49 pg/mg) proved that the driver had taken the drug over a long period of time.

Accidents, Traffic↗

PubMed1996

[A new tool for biological study: hair analysis. Value in medical practice].

Testing hair has been used since two hundred years for arsenic determination. Fifteen years ago, Baumgartner published the first report on the detection of morphine in the hair of heroin abusers by radio-immuno-assay. Today the development of new methods like gas chromatography/mass spectrometry has permitted numerous applications based on the analysis of organic substances trapped in hair. Personal observations and a review of the literature are presented in this paper to document the following clinical applications: hair as a screening procedure of psychiatric patients; hair and epileptic management; hair as a tool for monitoring neuroleptics; hair as evidence of gestational drug exposure; hair nicotine as a marker of passive exposure to tobacco; detection and clinical survey of heroin addict; evaluation of pharmaceutical exposure; hair analysis as a tool of clinical diagnosis; hair analysis for compliance monitoring.

Adult↗

PubMed1996

Sweat testing in opioid users with a sweat patch.

For many years, toxicologists have detected the presence of drugs of abuse in biological materials using blood or urine. In recent years, remarkable advances in sensitive analytical techniques have enabled the analysis of drugs in unconventional samples such as sweat. In a study conducted in a detoxification center, sweat patches were applied to 20 known heroin abusers. Subjects wore the patch with minimal discomfort for five days. During the same period, two urine specimens were also collected. Target drugs analyzed either by gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-mass spectrometry (LC-MS) included opiates (heroin, 6-monoacetylmorphine, morphine, codeine), cocaine (cocaine, benzoylecgonine, ecgonine methyl ester), delta 9-tetrahydrocannabinol, benzodiazepines (nordiazepam, oxazepam), amphetamines (amphetamine, methamphetamine, methylenedioxyamphetamine [MDA], methylenedioxymethamphetamine [MDMA], methylenedioxyethylamphetamine [MDEA]), and buprenorphine. Patches were positive for opiates in 12 cases. Heroin (37-175 ng/patch) and/or 6-acetylmorphine (60-2386 ng/patch) were identified in eight cases, and codeine exposure (67-4018 ng/patch) was determined in four cases. When detected, heroin was always present in lower concentrations than 6-acetylmorphine, which was the major analyte found in sweat. Cocaine (324 ng/patch) and metabolites were found in only one case. delta 9-Tetrahydrocannabinol (4-38 ng/patch) was identified in nine cases. Benzodiazepine concentrations were very low, ranging from 2 to 44 and from 2 to 15 ng/patch for nordiazepam and oxazepam, respectively. MDEA (121 ng/patch) and its metabolite, MDA (22 ng/patch), were detected in one case. Buprenorphine, which was administered as therapy under close medical supervision, was detected in the range 1.3-153.2 ng/patch with no apparent relationship between the daily dose and amount excreted in sweat. All the urine tests were consistent with the sweat findings, but to identify the same drugs it was necessary to test two urine specimens along with only one sweat specimen. It was concluded that sweat testing appears to offer the advantage of being a relatively noninvasive means of obtaining a cumulative estimate of drug exposure over the period of a week. This new technology may find useful applications in the treatment and monitoring of substance abusers, as the patch provides a long-term continuous monitor of drug exposure or noncompliance.

Amphetamines↗

PubMed1996

Drug testing in addicts: a comparison between urine, sweat, and hair.

The standard in drug testing is the immunoassay screen, followed by a gas chromatography/mass spectrometry confirmation conducted on a urine sample. Recently sweat and hair analyses were proposed for identifying drug abusers. Specimens can be collected under close supervision without embarrassment and are not subject to evasive maneuvers. In contrast with urine, hair analysis has a wide window of detection, ranging from months to years, and provides information concerning the severity and pattern of an individual's drug abuse. Testing individuals for illicit drugs with sweat patches worn continually would provide effective coverage for a week. Studies conducted in a detoxification center have shown that hair analysis is more sensitive for detecting illicit drug use than is urine screening. My experience in drug testing is discussed in the light of the existing literature.

Hair↗