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F Tagliaro

Publications and source records attributed to F Tagliaro.

At least 19 recordsLinked to original sources
PubMed2002

Determination of CDT, a marker of chronic alcohol abuse, for driving license issuing: immunoassay versus capillary electrophoresis.

The present work is aimed at a validation of the carbohydrate-deficient transferrin (CDT) determination in real cases by comparison between the a commercial immunometric method and a method based on capillary electrophoresis. Overall, 650 serum samples from subjects applying to re-obtain their driving license, previously withdrawn for "drunk driving", were investigated. A highly significant correlation (P < 0.001) was found between the results from immunoassay and capillary electrophoresis. However, particularly in the samples with CDT values around the cut-off or moderately elevated, a wide dispersion of the correlation data was found. This finding stresses the need to confirm by alternative techniques all the results from CDT immunoassays. For this purpose, capillary electrophoresis, because of its inherent characteristics of high selectivity, easy operation, high productivity and low operative costs looks well-suited for becoming the method of choice.

Adult↗
PubMed2002

Capillary zone electrophoresis and artificial neural networks for estimation of the post-mortem interval (PMI) using electrolytes measurements in human vitreous humour.

Determination of electrolyte concentrations (mainly potassium) in vitreous humour has long been considered an important tool in human death investigations for the estimation of the post-mortem interval (PMI). On the basis of its well known potential in ion analysis, capillary zone electrophoresis (CZE) has recently been applied to achieve a rapid and simultaneous determination of inorganic ions in this extracellular fluid. In the present work, artificial neural networks (ANN) were applied for modelling of the relationship of multicomponent CZE analysis of K+, NH4+, Na+, and Ba2+ ions in vitreous humour with PMI. In a study based on 61 cases with different causes of death and a known PMI ranging from 3 to 144 h, the use of ANNs considering all inorganic ion data from the human vitreous humour, achieved a substantial improvement of post-mortem interval prediction. Good linear correlation was observed (r2 = 0.98) and in comparison to the traditional linear least squares (LLS) method applied only to K+ levels in the vitreous humour, the prediction of PMI with ANN was improved by a factor of 5 from approximately +/- 15 h to less than 3 h.

Autopsy↗
PubMed2001

Potassium concentration differences in the vitreous humour from the two eyes revisited by microanalysis with capillary electrophoresis.

This paper presents a study of the variability of potassium concentrations in the vitreous humour of the two eyes of the same body at identical postmortem interval. The study was carried out by collecting microsample amounts (50 microl) of vitreous humour and by using an original method of capillary electrophoresis with indirect detection. The electrophoretic separations were carried out in a pH 4.5 running buffer composed of 5 mmol/l imidazole, 5 mmol/l 18-crown-6 ether and 6 mmol/l alpha-hydroxybutyric acid. Detection was by indirect UVabsorption at 214 nm. Vitreous humour samples were collected from 57 medico-legal autopsies or external examinations of cases of sudden natural or violent deaths. All samples prior to analysis were diluted 1:20 with a 40 microg/ml aqueous solution of barium, the used internal standard, and finally injected by nitrogen pressure. The mean concentrations of potassium measured in the two eyes of all the cases included in the present study ranged from 4.1 to 23.5 mmol/l with the postmortem interval values varying from 7 to 144 h. A highly significant (P<0.0001) linear correlation was found between these two parameters as described by the equation: y=0.1698x+2.3587, r=0.89. The intra-eye variability of potassium concentrations was low with an average RSD of 3.89% (+/- 1.83 SD) (48 eyes, five samples per eye). No statistically significant difference was found between the potassium concentrations in the two eyes of the same subject in a group of 24 cases, excepting a single case.

Electrophoresis, Capillary↗
PubMed2001

Use of beta-cyclodextrin in the capillary zone electrophoretic separation of the components of clandestine heroin preparations.

The present paper describes the methodological optimization and validation of a capillary zone electrophoresis method for the rapid determination of heroin, secondary products and additives present in clandestine heroin samples, by using 20 mM beta-cyclodextrins in phosphate buffer, pH 3.23. Applied potential was 15 kV and separation temperature was 24 degrees C; detection was by UV absorption at 200 nm wavelength. Heroin samples were first dissolved in CHCl3-MeOH (96:4, v/v) and injected by pressure (0.5 p.s.i., 3 s; 1 p.s.i.=6894.76 Pa) after evaporation of the organic mixture and reconstitution in aqueous buffer. Under the described conditions, phenylethylamine (internal standard), morphine, monoacetylmorphine, heroin, acetylcodeine, papaverine, codeine and narcotine were baseline resolved in less than 10 min. The limit of detection was better than 1 microg/ml for each analyte. The study of the intra-day and day-to-day precision showed, in terms of migration times, RSDs < or = 0.71% and, in terms of peak areas, RSDs < or = 3.2%. Also, the evaluation of linearity and analytical accuracy of the method provided good results for all the analytes investigated, thus allowing its application to real cases of seized controlled drug preparations.

Cyclodextrins↗
PubMed2001

Optimised determination of clobazam in human plasma with extraction and high-performance liquid chromatography analysis.

The analysis of clobazam by high-performance liquid chromatography and UV detection is described herein. After adding an internal standard, 600 microl of plasma were extracted under basic conditions onto disposable cartridges packed with celite. The organic extract was then evaporated to dryness and the residue reconstituted in 200 microl of mobile phase. A 20 microl aliquot was injected into chromatograph. The HPLC system was equipped with an Ultrasphere C8 analytical column coupled with an UV detector set at 235 nm. The mobile phase was an acetate buffer 20 mM, pH 5.5, containing acetonitrile and triethylamine 70:30:0.01 (v/v); the flow-rate was 1.8 ml/min. Using this method, clobazam can be detected with a sensitivity limit of 6 ng/ml and the RSD% intra- and inter-assay were lower than 5%. For its ruggedness and reliability, the proposed method is particularly suitable for therapeutic drug monitoring in epilepsy.

Anti-Anxiety Agents↗
PubMed2000

Capillary electrophoretic separation of vitamins in sodium dodecyl sulfate containing buffers with lower aliphatic alcohols and n-hexane as organic modifiers.

The effect of lower organic alcohols as co-surfactants (methanol, ethanol, n-propanol, isopropanol, propanediol, n-butanol and isoamylalcohol) and n-hexane as an organic modifier in 12.5 mol/l phosphate buffer with varying SDS concentration was investigated using a set of vitamins and p-hydroxybenzoic acid as the test mixture. It was demonstrated that optimum separations can be achieved particularly at high concentrations of the surfactant; the selectivity can be changed by adding a co-surfactant; while propanol and isopropanol show the same properties as co-surfactants, the most efficient alcohols were isoamylalcohol and propanediol. n-Butanol was capable of selective separation of p-hydroxybenzoic acid in the test mixture. Addition of ethanol appears most effective at higher concentrations (while all the other alcohols are effective already at 5% concentration, the best results with ethanol were obtained when it constituted 20% of the background electrolyte). 5% Concentration of methanol resulted in poor separation of the test mixture, however if 300 microl/10 ml of hexane were added to 20 mmol/l SDS containing phosphate buffer, the resulting separation was practically the same as with 50 mmol/l SDS.

Alcohols↗
PubMed2000

Improved method for carbohydrate-deficient transferrin determination in human serum by capillary zone electrophoresis.

Carbohydrate-deficient transferrin (CDT) is a reliable marker of chronic or repeated alcohol abuse. It indicates a group of isoforms of human transferrin (Tf), the main iron transport serum protein, deficient in sialic acid residues (asialo-, monosialo- and disialo-Tf) in comparison to the main isotransferrin which contains four sialic acid groups (tetrasialo-Tf). The aim of the present work was to develop a capillary electrophoretic method suitable for rapid determination of CDT components in serum. Serum samples (0.1 ml) were saturated with iron by incubation with 10 mM FeCl3 (2 microl) and 500 mM NaHCO3 (3 microl) for 30 min, then diluted 1:10 in water and injected by positive pressure (0.5 p.s.i. for 10 s). Separation was performed with a capillary zone electrophoretic method using bare fused-silica capillaries (57 cm x 20 microm I.D.) and a buffer composed of 100 mM sodium tetraborate adjusted with 6 M HCl to pH 8.3 added with 1.5 mM diaminobutane. Applied voltage was 20 kV and temperature 25 degrees C. Detection was by UV absorption at 200 nm wavelength. Under the described conditions, asialo-, monosialo-, disialo-, trisialo- and tetrasialo-transferrin were baseline separated. The limit of detection (signal-to-noise ratio of 2) was about 0.3% for disialo-Tf, and 0.5% of trisialo-Tf, expressed as percentages of the terasialo-Tf peak area. Day-to-day RSDs of relative migration times were < or = 0.2%. Quantitation showed day-to-day RDSs < or = 6.9% and < or = 10.9% for disialo- and trisialo-Tf, respectively. The results from 79 control subjects, including social drinkers, and 23 alcoholics showed disialo- and trisialo-Tf significantly increased in patients (P<0.0001 and <0.01, respectively). A clear interference from trisialo-Tf in an immunoassay for CDT was demonstrated. The present method is suitable for confirmation of CDT immunoassays by independent technique.

Electrophoresis, Capillary↗
PubMed2000

Hair analysis by using radioimmunoassay, high-performance liquid chromatography and capillary electrophoresis to investigate chronic exposure to heroin, cocaine and/or ecstasy in applicants for driving licences.

The present paper describes an integrated diagnostic strategy to check the physical fitness of subjects, formerly users of illicit drugs, to obtain a driving license, after having quit their addiction. According to the Italian law, applicants for a driving license with a history of drug abuse must give evidence to have quit this behaviour and to show no risk of relapse in the future. To prove this, at our institute, they undergo medical examination, hair analysis and a urinalysis program on eight seriate samples, collected over about 40 days. About 700 subjects per year are investigated with this strategy. The hair samples are screened for opiates (morphine), cocaine and ecstasy, the most abused illicit substances in our region, by using commercial radioimmunoassays adopting cut-off levels of 0.1 ng/mg. All positive samples and about 10% of negatives are confirmed by high-performance liquid chromatography. Further confirmation of results can be carried out by capillary electrophoresis (and/or GC/MS or MS/MS). In 1998, the prevalence of positives for morphine, cocaine and ecstasy was 4.8, 11.3 and 2.6%, respectively. In this year, for the first time, the percentage of hair samples positive for cocaine was greater than that for opiates. The results of this integrated diagnostic strategy are presented and discussed, with particular emphasis on the comparison between hair analysis on a single sample and seriate urinalyses (on eight samples).

Automobile Driving↗
PubMed2000

Field-amplified sample stacking capillary zone electrophoresis applied to the analysis of opiate drugs in hair.

The present paper describes the methodological optimization and validation of capillary zone electrophoresis (CZE) for the determination of major opiates (morphine, codeine, 6-monoacetylmorphine, acetylcodeine, heroin) in hair samples by using a field-amplified sample stacking injection before the separation in a binary running buffer (0.1 M sodium phosphate, pH 2.5, with 40% ethylene glycol). The applied potential was 20 kV, at 25 degrees C. Detection was by UV absorption at the fixed wavelength of 214 nm or by recording the full spectrum between 190-400 nm, thus improving the analytical selectivity and identification power of CZE. Hair samples were liquid/liquid extracted; dried extracts, reconstituted with a low-conductivity solvent (0.1 mM phosphoric acid, with 80% 1-propanol), were injected by electromigration at 10 kV for 99 s, after a 0.5 mm plug of water. Under the described conditions, the limit of detection (with a signal-to-noise ratio of 3) in hair extracts was 100 pg/mL for codeine, 75 pg/mL for morphine and 6-monoacetylmorphine (6-MAM), 150 pg/mL for ethylmorphine, and 0.75 ng/mL for acetylcodeine and heroin. The precision of the method was validated for standards in pure solution by using internal standardization, providing for intraday and day-to-day assays, in terms of migration times, relative standard deviation (RSD) values < or = 0.2%, and in terms of peak areas, RSD values <5.71%.

Electrophoresis, Capillary↗
PubMed2000

Capillary electrophoresis: a new analytical tool for forensic toxicologists.

In capillary electrophoresis, electrophoretic or electrokinetic separations are carried out in tiny capillaries at high voltages (10-30 kV), thus achieving high efficiency (N > 105), resolution power, and mass sensitivity (down to 10(-18)-10(-20) moles). The main characteristics of capillary electrophoresis are versatility of application (from inorganic ions to large DNA fragments), use of different separation modes with different selectivity, low demands on sample volume, negligible running costs, possibility of interfacing with different detection systems including mass spectrometry, and the ruggedness and simplicity of the instrumentation. Capillary electrophoresis applications in the forensic sciences are now rapidly growing, particularly in forensic toxicology. The present paper briefly describes the basic principles of capillary electrophoresis and presents a selected review of its main applications to the analysis of illicit/controlled drugs in biologic samples. An original analytical approach to the determination of carbohydrate deficient transferrin, a new marker of chronic alcohol abuse, based on capillary electrophoresis is also described. It is concluded that the peculiar separation mechanisms and the high complementarity of capillary electrophoresis to chromatography make it a new powerful tool of investigation in the hands of forensic toxicologists.

Electrophoresis, Capillary↗
PubMed2000

Analysis of morphine by RIA and HPLC in fingernail clippings obtained from heroin users.

Heroin is abused around the world and is frequently reported as the cause of death in overdose cases. Analysis of morphine in hair has been used in the past in forensic toxicology to study the addiction history of heroin addicts. The purpose of the present study was to evaluate the usefulness of the nail as an analytical specimen in the identification and quantification of morphine in fingernail clippings of known heroin users. Fingernail clippings were obtained from 26 consenting patients of the Glasgow Drug Problem Service. At the time of sampling, the participants provided answers to a questionnaire regarding their drug use patterns. Samples were decontaminated by sonication in SDS, deionized water and methanol, and the methanolic washes were screened for analyte presence. The washed nail clippings were then hydrolyzed and extracted. RIA was used for the screening and HPLC for the confirmation of morphine. Positive RIA results were obtained with nail clippings from 25 of the 26 heroin users. The levels ranged from 0.06 to 4.69 ng/mg with a mean morphine concentration of 1.67 ng/mg. HPLC results were positive for 22 of the 26 nail samples. The mean morphine level by HPLC was 2.11 ng/mg with a range from 0.14 to 6.90 ng/mg. Based on these results, we suggest that nails have the potential of becoming a powerful alternative to hair for the detection of past heroin use in forensic cases.

Adult↗
PubMed2000

[Alcohol, drugs, pharmacologic agents, and street safety].

Deaths due to road accidents during weekends have become a worrying phenomenon in Italy. With the aim of highlighting the role of psychotropic substances (alcohol, drugs of abuse) in causing road accidents, a survey based on clinical and chemico-toxicological analyses has been carried out on car drivers in the Veneto region during night weekends since 1994. Rapid clinical screening was carried out on 7952 drivers. 1399 of these, suspected to be under the influence of psychotropic substances, were subjected to complete clinical and toxicological ascertainment involving the following procedures: a) anamnesis, aiming at evidence of possible current or past use of psychotropic substances; b) objective clinical examination, aiming at finding evidence of recent (signs of acute or chronic intoxication) or past use (signs of withdrawal or associated organic pathologies) of psychotropic substances; c) double sampling of blood and urine and chemico-toxicological analysis using immunochemical, GC-HS and GC/MS-SIM techniques. As well as many data of social and behavioural interest, processing of results demonstrated that: a) 56.7% of the drivers examined had consumed alcoholic beverages; b) 30.4% had BACs higher than the threshold permitted in Italy (80 mg/100 ml); c) 15.7% of drivers were found to be under the influence of drugs of abuse or psychoactive drugs; d) the most frequently found substances were (in order): cannabinoids, stimulants (cocaine, amphetamines), opiates.

Accidents, Traffic↗
PubMed1999

Capillary zone electrophoresis of potassium in human vitreous humour: validation of a new method.

The analysis of potassium in the vitreous humour has long been regarded as an important tool in medicolegal and forensic toxicological investigation, particularly for the determination of the post-mortem interval. The present work was aimed at the optimisation and validation of a reliable, simple and fast capillary electrophoresis method for potassium analysis in the human vitreous humour with indirect UV detection at a wavelength of 214 nm. Electrophoretic separations were carried out in a running buffer comprising 5 mM imidazole, 5 mM 18-crown-6 ether and 6 mM D,L alpha-hydroxybutyric acid (HIBA), adjusted to pH 4.5. Constant voltage runs were carried out by applying a voltage of 500 V/cm at 25 degrees C. The samples were injected in the hydrodynamic mode at the anodic end of the capillary (0.5 p.s.i. for 10 s; 1 p.s.i. = 6894.76 Pa). The method showed good linearity in the concentration range from 6.5 mM to 16.25 microM, with an r2 value of 0.9994. The limit of detection, based on a signal-to-noise ratio of three, was 9.0 microM. Absolute intra-day RSDs of migration times were <0.40%, while the day-to-day values were < or =1.72%. Absolute peak area reproducibility was always better than 2.50%. A comparison of capillary electrophoresis with flame photometry on twelve real autopsy samples showed an excellent correlation with an r2 value of 0.9333. A preliminary application to real cases (20 subjects) was carried out plotting vitreous humour potassium vs. post-mortem interval with a resulting r2 of 0.904 and a Y-intercept of 4.75 mM, in agreement with the existing literature.

Aqueous Humor↗
PubMed1999

High sensitivity simultaneous determination in hair of the major constituents of ecstasy (3,4-methylenedioxymethamphetamine, 3,4-methylenedioxyamphetamine and 3,4-methylene-dioxyethylamphetamine) by high-performance liquid chromatography with direct fluorescence detection.

A simple, but sensitive and specific high-performance liquid chromatographic assay for the simultaneous determination of the major constituents of "ecstasy" [i.e. 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxyethylamphetamine (MDE)] with direct fluorimetric detection, particularly intended for the routine analysis of hair, is described. Hair samples (100 mg) were overnight incubated in 1 ml of 0.25 M HCl at 45 degrees C and extracted with a commercial liquid-liquid method. The dried residue reconstituted with 500 microl of 0.05 M NaH2PO4 pH 5.2 was injected. Isocratic reversed-phase liquid chromatography was carried out on a column (250x4.6 mm I.D.) packed with spherical 5-microm poly(styrene-divinylbenzene) particles; the mobile phase was composed of 0.1 M potassium phosphate (pH 3)-acetonitrile (82:18). The excitation and the emission wavelengths were set to 285 and 320 nm, respectively. Under the described conditions, MDA, MDMA and MDE eluted in symmetric peaks with an analysis time of 30 min. The limit of detection was lower than 1 ng/ml, with a signal-to-noise ratio of 5, for each compound in solution, allowing a cut-off of 0.1 ng/mg in the hair matrix to be established. The intra-day precision (n = 6) of the assay was characterised by RSDs between 1.0 and 3.0% and between 0.52 and 0.88% for concentrations of 10 and 100 ng/ml, respectively; in day-to-day precision tests (n = 6), RSDs ranged between 5.12 and 11.12%, respectively, for the same concentrations. Interferences from as many as 92 therapeutic and/or abused drugs currently in use in the population were excluded, including N-methyl-1-(3,4-methylenedioxyphenyl)-2 butanamine (MBDB).

Chromatography, High Pressure Liquid↗
PubMed1998

Determination of thyroxine in the hair of newborns by radioimmunoassay with high-performance liquid chromatographic confirmation.

Hair analysis is often used in forensic toxicology to study, retrospectively, chronic exposure of individuals to drugs, and consequently newborn hair may become an ideal sample to study intrauterine exposure to xenobiotics as well as to endogenous compounds. As a tool to investigate a supposed maternal thyroxine (T4) supply to the congenital hypothyroid fetus, we devised to use the analysis of T4 extracted from newborn hair. In the present paper, the analytical method based on T4 extraction from hair followed by a radioimmunoassay is described. To verify the nature of the T4-like immunoreactive material present in newborn hair, it was further studied by HPLC fractionation with radioimmunoassay of the eluted fractions. On the basis of a clear correspondence between retention times of T4 standard and T4-immunoreactive compound extracted from hair, we assigned this immunoreactive material to T4. Then, we determined T4 hair concentrations in 19 control newborns at birth and 12 congenital hypothyroid infants at 22 days of life. Values obtained from hypothyroid infants (31.47+/-8.8 pg/mg(hair), mean+/-S.D.) were not significantly lower than those obtained from healthy newborns at birth (36.10+/-13.2 pg/mg(hair)). Such results are in agreement with the hypothesis of a maternal supply of thyroxine to the fetus through placental crossing.

Chromatography, High Pressure Liquid↗
PubMed1998

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.

Body Fluids↗
PubMed1998

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.

Adult↗