Development and validation of a method for the simultaneous analysis of fatty acid ethyl esters, ethyl sulfate and ethyl glucuronide in neonatal meconium: application in two cases of alcohol consumption during pregnancy.

Alcohol consumption during pregnancy constitutes one of the leading preventable causes of birth defects and neurodevelopmental disorders in the exposed children. Fatty acid ethyl esters (FAEEs), ethyl glucuronide (EtG) and ethyl sulfate (EtS) have been studied as potential biomarkers of alcohol consumption. However, most analytical approaches proposed for their analysis in meconium samples consist of separated extraction procedures requiring the use of two meconium aliquots, which is costly in terms of both time and materials. Therefore, the aim of this study was to develop and validate a method for the simultaneous extraction of 9 FAEEs, EtG and EtS from one meconium aliquot. The sample was homogenized using methanol, and then FAEEs were extracted with hexane while EtG and EtS were isolated using acetonitrile. Then, extracts were applied to solid-phase extraction columns and analysed by gas chromatography mass spectrometry (FAEEs) and liquid chromatography tandem mass spectrometry (EtG and EtS). Calibration curves were linear with r values greater than 0.99. The LODs ranged from 0.8 to 7.5 ng/g for FAEEs and were 0.2 ng/g and 0.8 ng/g for EtS and EtG, respectively. LOQs ranged from 5 to 25 ng/g for FAEEs and were 1 ng/g and 2.5 ng/g for EtS and EtG, respectively. Accuracies and precisions were between 93.8 and 107% and between 3.5 and 9.7%, respectively. The recovery values ranged from 89.1 to 109%. The method proved to be sensitive, specific, simple and fast and allowed for the reduction of the amount of organic solvent used for extraction compared to other published data while higher recoveries were obtained. The method was used for analysis of meconium samples in two cases of mothers who were consuming alcohol during pregnancy.

Fast, sensitive and reliable multi-residue method for routine determination of 34 pesticides from various chemical groups in water samples by using dispersive liquid-liquid microextraction coupled with gas chromatography-mass spectrometry.

A simple and efficient dispersive liquid-liquid microextraction technique (DLLME) was developed by using a mixture of two solvents: 40 µL of tetrachlorethylene (extraction solvent) and 1.0 mL of methanol (disperser solvent), which was rapidly injected with a syringe into 10 mL of water sample. Some important parameters affecting the extraction efficiency, such as type and volume of solvents, water sample volume, extraction time, temperature, pH adjustment and salt addition effect were investigated. Simultaneous determination of 34 commonly used pesticides was performed by using gas chromatography coupled with mass spectrometry (GC-MS). The procedure has been validated in order to obtain the highest efficiency at the lowest concentration levels of analytes to fulfill the requirements of regulations on maximum residue limits. Under the optimum conditions, the linearity range was within 0.0096-100 µg L-1. The limits of detection (LODs) of the developed DLLME-GC-MS methodology for all investigated pesticides were in the range of 0.0032 (endrin)-0.0174 (diazinon) µg L-1 and limits of quantification (LOQs) from 0.0096 to 0.052 µg L-1. At lower concentration of 1 µg L-1 for each pesticide, recoveries ranged between 84% (tebufenpyrad) and 108% (deltamethrin) with relative standard deviations (RSDs) (n = 7) from 1.1% (metconazole) to 11% (parathion-mehtyl). This methodology was successfully applied to check contamination of environmental samples. The procedure has proved to be selective, sensitive and precise for the simultaneous determination of various pesticides. The optimized analytical method is very simple and rapid (less than 5 min). Graphical abstract Analytical procedure for testing water samples consists of dispersive liquid-liquid microextraction (DLLME) and gas chromatography coupled with mass spectrometry (GC-MS).

Effects of addictive substances during pregnancy and infancy and their analysis in biological materials.

The use of addictive substances during pregnancy is a serious social problem, not only because of effects on the health of the woman and child, but also because drug or alcohol dependency detracts from child care and enhances the prospect of child neglect and family breakdown. Developing additive substance abuse treatment programs for pregnant women is socially important and can help ensure the health of babies, prevent subsequent developmental and behavioral problems (i.e., from intake of alcohol or other additive substances such as methamphetamine, cocaine,or heroine) and can reduce addiction costs to society. Because women of childbearing age often abuse controlled substances during their pregnancy, it is important to undertake biomonitoring of these substances in biological samples taken from the pregnant or nursing mother (e.g., blood, urine,hair, breast milk, sweat, oral fluids, etc.), from the fetus and newborn (e.g., meconium,cord blood, neonatal hair and urine) and from both the mother and fetus (i.e.,amniotic fluids and placenta). The choice of specimens to be analyzed is determined by many factors; however, the most important is knowledge of the chemical and physical characteristics of a substance and the route of it administration. Maternal and neonatal biological materials reflect exposures that occur over a specific time period, and each of these biological specimens has different advantages and disadvantages,in terms of accuracy, time window of exposure and cost/benefit ratio.Sampling the placenta may be the most important biomonitoring choice for assessing in utero exposure to addictive substances. The use of the placenta in scientific research causes a minimum of ethical problems, partly because its sampling is noninvasive, causes no harm to mother or child, and partly because, in any case,placentas are discarded and incinerated after birth. Such samples, when properly analyzed, may provide key essential information about fetal exposure to toxic substances, and may provide the groundwork for protecting the fetus or newborn and the mother from further damage.Several sensitive and specific bioanalytical methods are commonly utilized to accurately measure for drug biomarkers of in utero drug exposure. Moreover, several immunoassay methods are used to rapidly screen for drugs in many biological specimen types. However, results from immunoassays should be carefully interpreted,and should be confirmed by more specific and sensitive chromatographic methods, such as GC-MS or LC-MS. Although techniques for analysis of addictive substances are still being developed or are being refined, current methods are efficient and sensitive and provide valuable information on human exposures to addictive substances and their metabolites.

Contributors to Preterm Birth: Data from a Single Polish Perinatal Center.

Preterm birth may result from overlapping causes including maternal age, health, previous obstetric history and a variety of social factors. We aimed to identify factors contributing to preterm birth in respect to new social and environmental changes in the reproductive patterns. Our cross-sectional study included 495 mother-infant pairs and was based on maternal self-reporting in an originally developed questionnaire. Neonates were divided into two groups: 72 premature babies (study group) and 423 full-term babies (control group). We analyzed maternal, sociodemographic and economic characteristics, habits, chronic diseases, previous obstetric history and pregnancy complications. For statistical analysis, Pearson's Chi-squared independence test was used with a statistical significance level of 0.05. Preterm births were more common among mothers living in villages (p < 0.001) and with lower education level (p = 0.01). Premature births were also positively associated with mothers who were running their own businesses (p = 0.031). Mothers with a history of previous miscarriages gave birth at a significantly older age (p < 0.001). The most frequent pregnancy complications were hypothyroidism (41.4%), pregestational and gestational diabetes mellitus (DM; 17.8%) and hypertension (8.1%). Pregestational DM significantly influenced the occurrence of prematurity (p < 0.05). Pregestational DM, being professionally active, a lower education level and living outside cities are important risk factors of prematurity.

Chiral analysis of chloro intermediates of methylamphetamine by one-dimensional and multidimentional NMR and GC/MS.

Impurity profiling and classification of abused drugs using chiral analytical techniques is of particular interest and importance because of the additional information obtained from this approach. When these methods are applied to the synthesis of illicitly used substances, they can supply valuable information about the conditions/chemicals used in the synthesis. We have applied GC and NMR methods to the study of intermediates found in methylamphetamine manufacture with the aim of linking the intermediates to the ephedrine/pseudoephedrine starting materials. Therefore, determination of the stereochemical makeup within samples of forensic interest is important giving further specific information to the analyst. This study investigates the stereochemical course of the Emde synthesis of methylamphetamine with particular focus on intermediate formation via the chlorination of ephedrine and pseudoephedrine enantiomers. The configurations of these chloro-phenethylamines were determined by 1D and 2D NMR analysis, and thereafter, the GC/MS analysis was carried out. We have shown here that chlorination of the ephedrine/pseudoephedrine compounds occurs via inversion (S(N)2) and retention (S(N)i) of configuration around the α carbon and mixture of diastereoisomers (chloroephedrine and chloropseudoephedrine) were formed, with the ratio of the resulting compounds dependent on the precursors used. The preparation and analytical properties of these intermediate standards provide data for laboratories interested in the stereochemical analysis of methylamphetamine intermediates such as forensic/law enforcement, and illustrate the value of using a combination of analytical methodology.

Chiral gas chromatography as a tool for investigations into illicitly manufactured methylamphetamine.

The aim of this study was to develop a chiral gas chromatographic method for the separation of compounds likely to be found in the EMDE synthesis of methylamphetamine, a heavily abused stimulant drug. Here we describe the separation of the enantiomers of ephedrine, pseudoephedrine, chlorinated intermediates and methylamphetamine using fluorinated acid anhydrides as chemical derivatization reagents prior to gas chromatographic analysis on a 2,3-di-O-methyl-6-t-butyl silyl-ß-cyclodextrin stationary phase (CHIRALDEX™ B-DM). Separation of the enantiomers of pseudoephedrine, methylamphetamine and chloro-intermediates was achieved using PFPA derivatization, and enantiomers of ephedrine using TFAA derivatization, in run times of less than 40 minutes. The use of HFBA as a derivatization reagent for this set of analytes is also discussed.

Green aspects of techniques for the determination of currently used pesticides in environmental samples.

Pesticides are among the most dangerous environmental pollutants because of their stability, mobility and long-term effects on living organisms. Their presence in the environment is a particular danger. It is therefore crucial to monitor pesticide residues using all available analytical methods. The analysis of environmental samples for the presence of pesticides is very difficult: the processes involved in sample preparation are labor-intensive and time-consuming. To date, it has been standard practice to use large quantities of organic solvents in the sample preparation process; but as these solvents are themselves hazardous, solvent-less and solvent-minimized techniques are becoming popular. The application of Green Chemistry principles to sample preparation is primarily leading to the miniaturization of procedures and the use of solvent-less techniques, and these are discussed in the paper.

Rapid method for the determination of organochlorine pesticides and PCBs in fish muscle samples by microwave-assisted extraction and analysis of extracts by GC-ECD.

A procedure for the multiresidue determination of organochlorine pesticides and polychlorinated biphenyls in fish muscle samples has been developed. The method is based on the microwave-assisted extraction (MAE) of food samples from an acetonitrile-water (95 + 5, v/v) mixture followed by SPE cleanup of the extracts and analysis by GC with an electron capture detector. MAE operational parameters, such as the extraction solvent, temperature, and time, were optimized with respect to the extraction efficiency of the target compounds from food samples with 10-13% fat content. The chosen extraction technique allows reduction of the solvent consumption and extraction time when compared with methods already used. Acetonitrile is a good extraction solvent for low-fat matrixes (2-20% fat content), such as fish samples, because it does not significantly dissolve the highly polar proteins, salts, and sugars commonly found in food and gives high recoveries of a wide polarity range of analytes. For purification, SPE using LC-Florisil was shown to be sufficient for the removal of coextracted substances. Recoveries > 78% with RSD values < 15% were obtained for all compounds under the selected conditions. Method quantification limits were in the 5-10 microg/kg range. The method was applied to the analysis of samples of herring (Clupea harengus) purchased at the local fish market. The method is rapid and reliable for the determination of organochlorine analytes in fish muscle.

Environmental fate and global distribution of polychlorinated biphenyls.

In recent decades, regulators, academia, and industry have all paid increasing attention to the crucial task of determining how xenobiotic exposures affect biota populations, communities, or entire ecosystems. For decades, PCBs have been recognized as important and potentially harmful environmental contaminants. The intrinsic properties of PCBs, such as high environmental persistence, resistance to metabolism in organisms, and tendency to accumulate in lipids have contributed to their ubiquity in environmental media and have induced concern for their toxic effects after prolonged exposure. PCBs are bioaccumulated mainly by aquatic and terrestrial organisms and thus enter the food web. Humans and wildlife that consume contaminated organisms can also accumulate PCBs in their tissues. Such accumulation is of concern, because it may lead to body burdens of PCBs that could have adverse health effects in humans and wildlife. PCBs may affect not only individual organisms but ultimately whole ecosystems. Moreover, PCBs are slower to biodegrade in the environment than are many other organic chemicals. The low water solubility and the low vapor pressure of PCBs, coupled with air, water, and sediment transport processes, means that they are readily transported from local or regional sites of contamination to remote areas. PCBs are transformed mainly through microbial degradation and particularly reductive dechlorination via organisms that take them up. Metabolism by microorganisms and other animals can cause relative proportions of some congeners to increase while others decrease. Because the susceptibility of PCBs to degradation and bioaccumulation is congener-specific, the composition of PCB congener mixtures that occur in the environment differs substantially from that of the original industrial mixtures released into the environment. Generally, the less-chlorinated congeners are more water soluble, more volatile, and more likely to biodegrade. On the other hand, high-chlorinated PCBs are often more resistant to degradation and volatilization and sorb more strongly to particulate matter. Some more-chlorinated PCBs tend to bioaccumulate to greater concentrations in tissues of animals than do low-molecular-weight ones. The more-heavily chlorinated PCBs can also biomagnify in food webs. Other high-molecular-weight congeners have specific structures that render them susceptible to metabolism by such species as fish, crustacea, birds, and mammals. In recent years, there has been substantial progress made in understanding the human health and ecological effects of PCBs and their environmental dynamics. However, risk assessments based only on the original PCB mixture that entered the environment are not sufficient to determine either (1) the persistence or toxicity of the weathered PCB mixture actually present in the environment, or (2) the risks to humans and the ecosystem posed by the weathered mixture. In this paper, we have reviewed the status of current knowledge on PCBs with regard to environmental inputs, global distribution, and environmental fate. We conclude that to know and understand the critical environmental fate pathways for PCBs, both a combination of field studies in real ecosystems and more controlled laboratory investigations are needed. For the future, both revised and new models on how PCBs behave in the environment are needed. Finally, more information on ow PCBs affect relevant physiological and behavioral characteristics of organisms tha are susceptible to contamination are needed.

Biomarkers of Alcohol Consumption in Body Fluids - Possibilities and Limitations of Application in Toxicological Analysis.

BACKGROUND: Ethyl alcohol is the most popular legal drug, but its excessive consumption causes social problems. Despite many public campaigns against alcohol use, car accidents, instances of aggressive behaviour, sexual assaults and deterioration in labor productivity caused by inebriated people is still commonplace. Fast and easy diagnosis of alcohol consumption is required in order to introduce proper and effective therapy, and is crucial in forensic toxicology analysis. The easiest method to prove alcohol intake is determination of ethanol in body fluids or in breath. However, since ethanol is rapidly metabolized in the human organism, only recent consumption can be detected using this method. Because of that, the determination of alcohol biomarkers was introduced for monitoring alcohol consumption over a wider range of time. OBJECTIVE: The objective of this study was to review published studies focusing on the sample preparation methods and chromatographic or biochemical techniques for the determination of alcohol biomarkers in whole blood, plasma, serum and urine. METHODS: An electronic literature search was performed to discuss possibilities and limitations of application of alcohol biomarkers in toxicological analysis. RESULTS: Authors described the markers of alcohol consumption such as: ethanol, its nonoxidative metabolites (ethyl glucuronide, ethyl sulfate, phosphatidylethanol, ethyl phosphate, fatty acid ethyl esters) and oxidative metabolites (acetaldehyde and acetaldehyde adducts). We also discussed issues concerning the detection window of these biomarkers, and possibilities and limitations of their use in routine analytical toxicology for monitoring alcohol consumption or sobriety during alcohol therapy.

Methods for determining pesticides and polychlorinated biphenyls in food samples--problems and challenges.

Determination of residual amounts of pesticides and polychlorinated biphenyls (PCBs) in food samples requires the use of specific techniques regarding sample preparation as well as instrumental analysis which should be characterized by a very low detection limit. A problem associated with the use of pesticides and PCBs is the need for controlling their residues in the environment, particularly in food, as these chemicals show a propensity to accumulate. The analysis of food samples for the presence of pesticides and PCBs brings on many difficulties because of the specificity of sample preparation consisting of multistep purification procedures of samples that contain trace amounts of an analyte. Concentration determinations of pollutants that easily dissolve in complex matrices, particularly in the presence of a large apportionment of interfering substances, pose a big challenge. Therefore, the basic step in food analysis for the presence of pesticides and PCBs is sample preparation which mainly consists of analyte enrichment and the removal of interfering substances. But all steps of the analytical procedure that include sample collection and preparation, extraction of analytes from matrix, extract purification, and final determination, are very significant; their precision and correct application have a decisive effect on the final result.

Applications of sample preparation techniques in the analysis of pesticides and PCBs in food.

Pesticides and polychlorinated biphenyls (PCBs) are found in various parts of the environment in quite small concentrations, but they accumulate and thus become a threat to human health and life. A review is focused on the application of some popular techniques for sample preparation in analysis of these compounds in food. Even with the emergence of advanced techniques of final analysis, complex matrices, such as food, require extensive sample extraction and purification. Traditional sample preparation techniques are time consuming and require large amount of solvents, which are expensive, generate considerable waste, contaminate the sample and can enrich it for analytes. There have been many sample preparation techniques proposed to meet the requirements connected with the multiplicity of food. Optimal sample preparation can reduce analysis time, sources of error, enhance sensitivity and enable unequivocal identification and quantification. Sample extraction and purification techniques are discussed and their most recent applications in food analysis are provided. This review pointed out that sample preparation is the critical step.

PCA and multidimensional visualization techniques united to aid in the bioindication of elements from transplanted Sphagnum palustre moss exposed in the Gdansk City area.

GOAL, SCOPE AND BACKGROUND: During the last decades, a technique for assessing atmospheric deposition of heavy elements was developed based on the principle that samples of moss are able to accumulate elements and airborne particles from rain, melting snow and dry deposition. Despite a broad interest in bioindication there are still ongoing works aimed at the preparation of a standard procedure allowing for a comparison of research carried out in various areas. This is why the comparison of living and dry moss of the same species and growth site seems to be interesting, logical and promising. A most reliable approach seems to be the application of bioindication connected with multivariate statistics and efficient visualization techniques in the interpretation of monitoring data. The aim of this study was: (i) to present cumulative properties of transplanted Sphagnum palustre moss with differentiation into dry and living biomaterial; (ii) to determine and geographically locate types of pollution sources responsible for a structure of the monitoring data set; (iii) to visualize geographical distribution of analytes in the Gdansk metropolitan area and to identify the high-risk areas which can be targeted for environmental hazards and public health. MATERIALS AND METHODS: A six month air pollution study based on Sphagnum palustre bioindication is presented and a simplified procedure of the experiment is given. The study area was located at the mouth of the Vistula River on the Baltic Sea, in Gdansk City (Poland). Sphagnum palustre was selected for research because of its extraordinary morphological properties and its ease in being raised. The capability of dry and living moss to accumulate elements characteristic for anthropogenic and natural sources was shown by application of Principal Component Analysis. The high-risk areas and pollution profiles are detected and visualized using surface maps based on Kriging algorithm. RESULTS: The original selection of elements included all those that could be reliably determined by Neutron Activation Analysis in moss samples. Elimination of variables covered the elements whose concentrations in moss were lower than the reported detection limits for INAA for most observations or in cases where particular elements did not show any variation. Eighteen elements: a, Ca, Sc, Fe, Co, Zn, As, Br, Mo, Sb, Ba, La, Ce, Sm, Yb, Lu, Hf, Th, were selected for the research presented. DISCUSSION: Two runs of PCA were performed since, in the first-run a heavy polluted location (Stogi - 'Sto') understood as outlier in the term of PCA approach was detected and results in the form of block diagrams and surface maps were presented. As ensues from the first-run PCA analysis, the factor layout for both indicators is similar but not identical due to the differences in the elements accumulation mechanism. Three latent factors ('phosphatic fertilizer plant impact', 'urban impact' and 'marine impact') explain over 89% and 82% of the total variance for dry and living moss respectively. In the second-run PCA three latent factors are responsible for the data structure in both moss materials. However, in the case of dry moss analysis these factors explain 85% of the total variance but they are rather hard to interpret. On the other hand living moss shows the same pattern as in first-run PCA. Three latent factors explain over 84% of the total variance in this case. The pollution profiles extracted in PCA of dry moss data differ tremendously between both runs, while no deterioration was found after removal of Stogi from data set in case of living moss. Performance of the second-run PCA with exception of Stogi as a heavy polluted location has led to the conclusion that living moss shows better indication properties than dry one. CONCLUSIONS: While using moss as wet and dry deposition sampier it is not possible to calculate deposition values since the real volume of collected water and dust is hard to estimate due to a splash effect and irregular surface. Therefore, accumulation values seam to be reasonable for moss-based air pollution surveys. Both biomaterials: dry and living Sphagnum palustre show cumulative properties relative to elements under interest. Dry moss has a very loose collection of the atmospheric particles, which can also easily get lost upon rinsing with rainwater running through exposed dry moss material. The living moss may, on the contrary, incorporate the elements in its tissue, thus being less susceptible to rinsing and thus better reflecting the atmospheric conditions. Despite the differences in element uptake and uphold capabilities dry and living moss reflect characteristic anthropogenic and natural profiles. Visible differences in impacts' map coverage exist mostly due to the accumulation mechanisms differentiating dry from living moss. However, in case of each indicator 'phosphatic fertilizer plant impact' is recognized as the strongest pollution source present in examined region. RECOMMENDATIONS AND PERSPECTIVES: General types of pollution sources responsible for a structure of monitoring data set were determined as high-risk/low-risk areas and visualized in form of geographic distribution maps. These locations can be targeted for environmental hazards and public health. Chemometric results in the form of easy defined surface maps can became a powerful instrument in hands of decision-makers working in the field of sustainable development implementation.

Application of gas chromatography-tandem mass spectrometry for the determination of amphetamine-type stimulants in blood and urine.

Amphetamine, methamphetamine, phentermine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), and 3,4-methylenedioxy-N-ethylamphetamine (MDEA) are the most popular amphetamine-type stimulants. The use of these substances is a serious societal problem worldwide. In this study, a method based on gas chromatography-tandem mass spectrometry (GC-MS/MS) with simple and rapid liquid-liquid extraction (LLE) and derivatization was developed and validated for the simultaneous determination of the six aforementioned amphetamine derivatives in blood and urine. The detection of all compounds was based on multiple reaction monitoring (MRM) transitions. The most important advantage of the method is the minimal sample volume (as low as 200µL) required for the extraction procedure. The validation parameters, i.e., the recovery (90.5-104%), inter-day accuracy (94.2-109.1%) and precision (0.5-5.8%), showed the repeatability and sensitivity of the method for both matrices and indicated that the proposed procedure fulfils internationally established acceptance criteria for bioanalytical methods The procedure was successfully applied to the analysis of real blood and urine samples examined in 22 forensic toxicological cases. To the best of our knowledge, this is the first work presenting the use of GC-MS/MS for the determination of amphetamine-type stimulants in blood and urine. In view of the low limits of detection (0.09-0.81ng/mL), limits of quantification (0.26-2.4ng/mL), and high selectivity, the procedure can be applied for drug monitoring in both fatal and non-fatal intoxication cases in routine toxicology analysis.

Blood concentrations of a new psychoactive substance 4-chloromethcathinone (4-CMC) determined in 15 forensic cases.

PURPOSE: The 4-chloromethcathinone (4-CMC) is a synthetic derivative of cathinone and belongs to new psychoactive substances. Neither data on the effects of 4-CMC on the human body, nor on nontoxic, toxic and lethal concentrations in biological materials have been published in the literature. This paper describes the results of an analysis of the blood concentrations of 4-CMC determined in 15 forensic cases related to nonfatal intoxication including driving under the influence, and fatalities including overdoses, suicide and traffic accidents. METHODS: A new method for the quantification of 4-CMC using gas chromatography-mass spectrometry (GC-MS) was developed. The symptoms of 4-CMC use were also studied based on an analysis of the documents prepared during the collection of samples or at autopsies. RESULTS: The limits of detection and quantification of the method for blood samples were 0.3 and 1 ng/mL, respectively. The calibration curve was linear in the studied concentration range (1-500 ng/mL) with the correlation coefficient at 0.9979. The extraction recoveries varied in the range of 94.3-98.8%. The accuracy and precision were acceptable. The determined concentrations in nonfatal cases ranged from 1.3 to 75.3 ng/mL, and in fatalities from 56.2 to 1870 ng/mL. CONCLUSIONS: Our study can assist in the recognition of the possible effects caused by 4-CMC and can be helpful during the preparation of forensic toxicological opinions for courts of law. The validation parameters indicate the sensitivity and accuracy of the method. This is the first work presenting a validated method for the determination of 4-CMC in blood samples by GC-MS.

Determination of MDPBP in postmortem blood samples by gas chromatography coupled with mass spectrometry.

ABSTRACT: MDPBP (1-(3,4-methylenedioxyphenyl)-2-(1-pyrrolidinyl)-1-butanone) is a new psychoactive substance sold on the black market. It has been a controlled drug of abuse in Poland and China since 2015 as some toxic and fatal cases connected with use of synthetic cathinone derivatives were observed. The fatal case outlined here concerns a 19-year-old man, who was found dead with an envelope containing white powder lying nearby the cadaver. The analyses of the powder revealed a presence of MDPBP. Due to this, blood was tested for routine toxicological analysis for traditional drugs and for MDPBP by liquid-liquid extraction procedure with 1-chlorobutane followed by GC-MS analysis. Full validation of proposed method was performed. Limit of detection and limit of quantification were 10.1 and 30.4 ng/cm3, respectively. Calibration curve was linear in studied concentration range (25-1000 ng/cm3) with a correlation coefficient 0.9946. The trueness and inter-day precision expressed as recoveries and CV values were investigated at 3 concentrations: 25, 250, and 1000 ng/cm3. The CV values were less than 20 % in the lowest concentration and less than 15 % in other concentrations what met the internationally established acceptance criteria for bioanalytical methods. It indicates good precision and accuracy of the method. The analysis of blood sample showed very high concentration of MDPBP (9.32 µg/cm3), which suggests possibility of overdosing. To the best of our knowledge, this is the first work which presents determination of MDPBP in blood by GC-EI-MS method and the third fatal accident report of MDPBP abuse.

Some aspects of the analysis of environmental pollutants in sediments using pressurized liquid extraction and gas chromatography-mass spectrometry.

Pressurized liquid extraction (PLE) is a fully automated extraction technique for isolation of analytes from solid samples. This technique combines elevated temperature and pressure of liquid solvents during the extraction process. In this study the efficiency of a PLE system for the isolation of wide range of analytes (polychlorinated biphenyls and organic pesticides from sediments under different pressure and temperature conditions) was investigated. The temperature 100 degrees C and pressure 6.9 MPa (1000 p.s.i.; 1 p.s.i.=6894.76 Pa) were found to be the most efficient from all investigated conditions. Using these PLE parameters, the average recoveries for most of the analytes were in the range 80-105% and relative standard deviation was usually under 15%. The conditions of determination of analytes in the extracts using GC-MS were established. Some problems occurring during the analysis of real samples, such as coelution of analytes, were established. The influence of internal standard addition on the final analysis results was determined.

Capillary gas chromatography using a γ-cyclodextrin for enantiomeric separation of methylamphetamine, its precursors and chloro intermediates after optimization of the derivatization reaction.

The enantiomeric ratio of methylamphetamine (MAMP) is closely related to the optical activity of precursors and reagents used for the synthesis and this knowledge can provide useful information concerning the origins and synthetic methods used for illicit manufacture. The information can be utilized for regulation of the precursors and investigation of the manufacturing sources but this requires analytical procedures to determine purity of drug substances, impurity profiling and enantiomeric composition. In this study, a gas chromatography (GC) coupled with mass spectrometry (MS) method using a γ-cyclodextrin chiral stationary phase was developed and optimized for the simultaneous enantiomeric separations of MAMP and its common precursors, ephedrine, and pseudoephedrine, as well as its chlorointermediates formed during MAMP synthesis by the Emde method, after derivatization with trifluoroacetic anhydride. The optimization was performed using multivariate statistics (cluster analysis and principal components analysis) in order to select and compare optimal experimental conditions. Under the optimized experimental conditions, the calculated calibration curves showed good linearity range up to 0.1µg/mL for all tested analytes. The limits of detection were in the range of 0.002-0.008µg/mL and the coefficient of variability was between 1.0 and 3.9%. The method has the advantage of achieving excellent precision under repeatability and reproducibility conditions while detection by MS allows for the identity of analytes to be confirmed in a single analysis. The method was therefore applied satisfactory to MAMP analysis.

Multi-residue method for the determination of 16 recently used pesticides from various chemical groups in aqueous samples by using DI-SPME coupled with GC-MS.

A simple and solvent-free multi-residue method has been optimized to determine 16 currently used pesticides from different chemical groups in aqueous samples. The extraction of analytes was carried out with direct immersion solid-phase microextraction (DI-SPME) and for the identification and quantitative determination gas chromatography coupled with mass spectrometry (GC-MS) was applied. Two commonly used adsorbent coatings have been applied and compared: 100 µm of polydimethylsiloxane (PDMS) and 85 µm of polyacrylate (PA). The method development parameters of DI-SPME, analyte desorption and GC-MS analysis have been outlined along with the final experimental conditions. When the optimum extraction conditions were applied (extraction time 60 min, 10% (w/v) NaCl solution, 45°C) the limits of detection (LODs) were in the range of 0.015-0.13 µgL(-1) and the relative standard deviations (RSDs) were between 1.9 and 9.6%. The developed analytical method was successfully applied to the analysis of natural water samples from the following sources: river, sea, canal and rain.