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Stanovení reziduí léčiv pomocí separačních metod / Determination of drug residuals using separation methodsVašíčková, Petra January 2010 (has links)
Nonsteroidal anti-inflammatory substances became a very frequently used and constantly evolved group of the drugs, particularly in a human medicine. The risk of their penetration into the environment, especially to the water environment, is rising during the recent years. The diploma thesis is focused on a selection of appropriate separation method and optimization of analytical procedure for the identification and determination of the non-steroidal anti-inflammatory drugs in sewage and surface waters. Salicylic acid, ketoprofen, diclofenac and ibuprofen were chosen from the wide range of NSAIDs as the most widespread agents of this drugs group in the medical practice. The method was optimized and elaborated using the model water samples. This method was used for determination of the analytes contained in the real water samples. Waste water samples were taken from the large-scale wastewater treatment plant in Brno-Modřice and surface water samples were taken from the Highlands river Křetínka. Solid phase extraction (SPE) was used for the real samples treatment and preconcentration, the determination was performed using the high performance liquid chromatography with mass spectroscopy method (LC-MS).
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Využití kapalinové chromatografie pro stanovení reziduí léčiv / The Use of Liquid Chromatography for Determination of Drug ResiduesDvořáková, Petra January 2012 (has links)
This work is based on the occurrence of drug residues in the environment. This study is focused on the development and optimization methods for determination of selected drugs in the surface water, aquatic sediment and sewage sludge from waste water treatment plant. From the group of drugs were chosen antibiotics. Antibiotics presented in the environment can cause adverse effects including toxic effects, immunity disorders and indirect bioalteration effects. Sulfonamide antibiotics, which are used in the treatment of urinary and respiratory tract infections as well as in the treatment of other infectious diseases, were chosen as a target compounds. Three optimized analytical methods for determination of sulfonamide antibiotics were developed. For the optimization of extraction were tested: solid phase extraction, pressurized solvent extraction, microwave extraction and ultrasonic extraction. For the final analysis was used liquid chromatography with two detectors - diode array detector and mass spectrometer. These optimized methods were applied for the analysis of real samples. The surface water and sediment samples were collected from two Moravian rivers (the Svratka river and the Svitava river). Samples of sewage sludge were collected from waste water treatment plant Brno-Modřice. Fish samples from the Svratka river were also collected. It was observed that all the selected sulfonamide antibiotics are present in real sediment samples (ug.kg-1). Simultaneously presence of some target analytes in real surface water (ug.l-1) and in sewage sludge (ug.kg-1) samples has been confirmed. In samples of surface water from the Svitava river and in fish samples sulfonamide antibiotics were not detected or their concentrations were below the limit of detection.
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Využití plynové chromatografie s hmotnostně spektrometrickou detekcí pro posouzení kontaminace odpadních a povrchových vod rezidui léčiv / Application of Gas Chromatography with Mass Spectrometric Detection for the Assessment of Drug-residue Contamination of Wastewaters and Surface WatersLacina, Petr January 2012 (has links)
This work is based on the current issue of increasing concentrations of pharmaceutical residues in various components of the environment. These new environmental contaminants continuously enter the environment. The most affected environmental component is the aquatic environment. This study is focused on the development and optimization of reliable analytical method, which can determine selected drugs in the aquatic environment (waste waters and surface waters) qualitatively and quantitatively. The target compounds were selected mainly from the group of non-steroidal anti-inflammatory drugs (NSAID): salicylic acid, acetylsalicylic acid, clofibric acid, ibuprofen, acetaminophen, caffeine, naproxen, mefenamic acid, ketoprofen and diclofenac. NSAIDs are one of the most used drugs in Czech Republic. For the final analysis of this study was used the comprehensive two-dimensional gas chromatography with mass spectrometric detection Time-of-Flight (GCxGC-TOF MS). It is a very sensitive and reliable analytical method for trace and ultra-trace analysis. Simultaneously, solid phase extraction (SPE) and derivatization are optimized in this work. Optimized analytical method including SPE, derivatization with MSTFA (N-methyl-N-(trimethylsilyl) trifluoroacetamide) and final analysis by GCxGC-TOF MS were applied successfully for the analysis of real samples. Samples of waste water were collected from the waste water treatment plant in Brno – Modřice and samples of surface water were collected from two river streams Svratka and Svitava in Moravian region. The range of concentrations of selected drug residues varied from one to tens of g/L in wastewater and from tens to hundreds of ng/L in surface waters. The degree of wastewater and surface waters contamination by drug residues is assessed in conclusions of the work. Simultaneously, spontaneous degradation of selected drugs in water and removal efficiency of the wastewater treatment plant is assessed in conclusions of the work. The developed method is usable for monitoring and environmental analysis of water ecosystems. It is usable not only for selected drugs, but even for other organic compounds with similar properties.
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Studium průniku PBDE a perfluorovaných sloučenin do vodních ekosystémů / Study of Exposure PBDE and Perfluorinated Compounds into Aquatic EcosystemVondráčková, Ilona January 2015 (has links)
In the presented PhD. thesis, problems covering occurrence of polybrominated diphenyl ethers (PBDE) and perfluorinated compounds in the environment were solved. The study was focused on identification and further verification of optimal methods in order to determine PBDEs and perfluorinated compounds sampled from the aquatic ecosystem. Polybrominated diphenyl ethers belong to persistent compounds classified as main pollutants; within the environmental constituents, they have been observed particularly in the last decade. For these studies, there were selected surface water matrices and sediments taken in various localities within the river Svratka basin. The analyses were to demonstrate whether they accumulate and remain in these specific matrices for longer time. There we assessed the congeners of polybrominated diphenyl ethers as follows: BDE-28, 47, 66, 85, 99, 100, 153, 154 and 183. In order to isolate them from matrices, various extraction techniques were used, i.e., ultrasonic extraction, microwave extraction, and pressure solvent extraction. Gas chromatography method with electron capture detection (GC/ECD) was selected for determination. The accomplished studies also assessed basic chemical, physical and environmental characteristics of diphenyl ethers in the environmental constituents. The attention was also paid to perfluorooctanoic compounds (PFOA), (PFOS) and (FOSA); physico-chemical properties of these organic pollutants were characterised and their toxicological and environmental aspects were evaluated. Usability of extraction techniques (ultrasonic extraction, pressure solvent extraction, solid phase extraction) applied to PFCs isolation from sediments samples was assessed. Identification and quantification of these analytes were performed using a high performance liquid chromatography/mass spectrometry method (HPLC/MS). After that, the optimized methods applied to real samples. Surface water and sediments were sampled within the river Svratka basin, in particular, from 19 sampling localities. PBDE occurrence was confirmed in sediments samples from the Svratka river (g.kg-1), PBDE were not detected in the surface water samples, their concentrations were below the detection limit, resp.; perfluorinated compounds were not detected in sediments and water samples at all.
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Využití moderních separačních a spektrometrických metod k identifikaci lipidomu z biologického vzorku / Modern separation and spectrometric techniques for biological sample lipidom investigationHavelková, Eva January 2013 (has links)
Modern separation and spectrometric techniques for biological sample lipidom investigation Due recent progress in field of mass spectrometry the lipidomics, part of metabolomics, is increasing its importance for broad fields of biological study. The aim of this study is to test the lipid extraction techniques and to optimize the preseparation and separation of lipids suitable for mass spectrometry detection. The fragmentation patterns of four, the most abundant lipid classes of glycerolipids (PC, PE, TG, DG), were acquired for the proposed system. These patterns were compared with literature. The most appropriate method for extraction was declared technique according Folch based on methanol and chloroform solution. The preseparation due SPE method is very useful tool for lipid determination. The optimized were focused to reach higher recovery especially in polar lipid fraction. Proposed HPLC system is based on methanol with ammonium buffer, water and isopropanol. The testing was done on three columns with different type of sorbents (Gemini, Syncronis and Kinetex). The separation was evaluated according mass spectrometer response, shape and wide of particular analytes peaks. Composition contains 20% of water was determinate as the best and also the best separation was achieved by Kinetex column. The proposed...
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Voltametrické a amperometrické stanovení nitrofenolů pomocí borem dopované diamantové filmové elektrody / Voltammetric and Amperometric Determination of Nitrophenols Using Boron-Doped Diamond Film ElectrodeKaraová, Jana January 2018 (has links)
Presented Ph.D. Thesis is focused on the use of the boron-doped diamond (BDD) electrodes for voltammetric and amperometric determination of selected nitrophenols: 2-nitrophenol (2NP), 4-nitrophenol (4NP), and 2,4-dinitrophenol (2,4DNP). These compounds are listed as "priority pollutants" by United States Environmental Protection Agency (US EPA) due to their negative impact on living organisms and are mainly used in agriculture as plant growth stimulators. BDD electrodes are used for determination of wide range of electrochemically both reducible and oxidisable organic compounds and have become a popular electrode material thanks to its commercial availability and excellent mechanical and electrochemical properties. A differential pulse voltammetric method was developed for the determination of 2NP, 4NP and 2,4DNP at a BDD film electrode using electrochemical reduction and of 4NP and 2,4DNP using electrochemical oxidation. The method was successfully applied for the direct determination of these compounds in drinking and river water in the concentration range from 4×10-7 to 2×10-5 mol.L-1 . To improve the limit of quantification, a preconcentration by solid phase extraction from 100 mL (drinking and river water) and 1000 mL (drinking water) of water samples was used with limit of determination...
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Rychlé metody analýzy migrantů z materiálů ve styku s potravinami / Fast methods for analysis of migrants from food-contact materialsVavrouš, Adam January 2020 (has links)
(AJ) Food contact materials pose a risk to human health due to a variety of contaminants which they can release into food. These compounds, migrants, include aromatic hydrocarbons, dialkyl phthalates, bisphenols, printing ink photoinitiators, and perfluoroalkyl compounds. The determination of all these substances can be expensive and time-consuming since universally applicable analytical approaches are not available nowadays. This work attempted to develop methods for the simultaneous determination of migrants from all of the mentioned groups in paper-based food contact materials and fatty food. A total of 68 contaminants were studied in paper products using liquid chromatography and gas chromatography coupled with tandem mass spectrometry detection. All analytes were isolated simultaneously using the modified "QuEChERS" method. This method demonstrated acceptable recovery and repeatability for most analytes in the validation study; LOQs ranged from 1.3 to 220 µg/kg. Analysis of 132 real paper products confirmed the occurrence of almost all studied analytes, which were often present in complex mixtures and at concentrations up to 628 mg/kg. A total of 41 potential contaminants were monitored in fatty foods by liquid chromatography with tandem mass detection. Contamination of the mobile phase by...
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Rychlé metody analýzy migrantů z materiálů ve styku s potravinami / Fast methods for analysis of migrants from food-contact materialsVavrouš, Adam January 2020 (has links)
(AJ) Food contact materials pose a risk to human health due to a variety of contaminants which they can release into food. These compounds, migrants, include aromatic hydrocarbons, dialkyl phthalates, bisphenols, printing ink photoinitiators, and perfluoroalkyl compounds. The determination of all these substances can be expensive and time-consuming since universally applicable analytical approaches are not available nowadays. This work attempted to develop methods for the simultaneous determination of migrants from all of the mentioned groups in paper-based food contact materials and fatty food. A total of 68 contaminants were studied in paper products using liquid chromatography and gas chromatography coupled with tandem mass spectrometry detection. All analytes were isolated simultaneously using the modified "QuEChERS" method. This method demonstrated acceptable recovery and repeatability for most analytes in the validation study; LOQs ranged from 1.3 to 220 µg/kg. Analysis of 132 real paper products confirmed the occurrence of almost all studied analytes, which were often present in complex mixtures and at concentrations up to 628 mg/kg. A total of 41 potential contaminants were monitored in fatty foods by liquid chromatography with tandem mass detection. Contamination of the mobile phase by...
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Analyse d’hormones stéroïdiennes par spectrométrie de masse dans les eaux du robinet, de surface et les eaux uséesGoeury, Ken 02 1900 (has links)
Il apparaît au grand jour que de nombreuses substances telles que les perturbateurs endocriniens sont introduites quotidiennement dans l’environnement. Ces molécules organiques bien souvent d’origine anthropique peuvent être employées dans d’innombrables circonstances : pharmaceutique, médecine, agriculture, cosmétique, agroalimentaire pour citer quelques exemples. Parmi ce large panel de composés, se trouvent les hormones stéroïdiennes. Un certain nombre de maladies et de modifications aussi bien comportementales que physiologiques tant chez l’humain que sur la faune aquatique sont attribuées à l’usage et aux rejets chroniques de ces perturbateurs endocriniens. Il est donc indispensable de développer une approche portée sur la prévention et l’étude des niveaux de contamination selon un seul maître-mot : précaution.
Dans ce contexte, ce projet de doctorat visait à développer de nouvelles méthodes de détection des hormones stéroïdiennes à niveau ultra-trace dans diverses matrices environnementales. La sélection des composés ciblés dans ce projet s’est basée sur la nouvelle liste de perturbateurs endocriniens prioritaires de l’agence de protection de l’environnement des États-Unis (US EPA), récemment élargie à d’autres classes de substances dont le bisphénol A. Les méthodes analytiques ont été développées non seulement dans l’eau du robinet (EPA 539), mais également dans d’autres matrices plus complexes (eaux de surface, eaux usées). Commune à l’ensemble des procédures testées, la phase de validation analytique a permis de vérifier la conformité avec les exigences de performance de l’EPA. La première méthode mise au point repose sur une pré-concentration rapide de l’échantillon par extraction sur phase solide en ligne (on-line SPE) couplée à la chromatographie liquide à ultra-haute performance (UHPLC) et à la spectrométrie de masse en tandem (MS/MS). La méthode validée présente de nombreux avantages—reproductibilité, automatisation, temps d’analyse minimal, logistique réduite et surtout des limites de détection de 0,10 ng·L-1 à 7,5 ng·L-1 selon les différentes matrices étudiées. Cette méthode apparaît particulièrement adaptée pour la détection des hormones dans les eaux usées, en lien avec les plus fortes concentrations attendues. Cependant, il est apparu pertinent d’améliorer encore la sensibilité des méthodes dans certains contextes, notamment dans le cadre des
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analyses d’eau de surface, compte tenu des critères de qualité applicables. La principale modification fut apportée au niveau de l’extraction et de la purification des échantillons. Amendée à la faveur des différentes matrices, l’étape d’extraction par SPE hors-ligne automatisée (off-line SPE) a permis d’atteindre des limites de détection adéquates variant de 0,010 ng·L-1 à 6,0 ng·L-1 dépendamment de la matrice et du composé. Un aspect original de cette étude a consisté à étudier de façon plus systématique les facteurs de robustesse de la méthode lorsque soumise à certaines variations, tant au niveau de l’analyse instrumentale (phases mobiles, volume d’injection) que des protocoles (emploi de différents agents de conservation, par exemple).
L’analyse de la phase dissoute ne saurait être suffisante pour comprendre le devenir environnemental des perturbateurs endocriniens dans les milieux aquatiques, notamment leur distribution. Dans cette optique, la phase particulaire en suspension dans la colonne d’eau (SPM) fut également étudiée après optimisation et validation de la méthode d’extraction. Les limites de détection obtenues étaient comprises entre 0,10 ng/g et 3,0 ng/g, un degré de performance adéquat au regard des teneurs attendues dans l’environnement.
De telles méthodes ne trouveraient pas de fondement si elles n’étaient pas employées à l’analyse d’échantillons réels. C’est pourquoi, pour chaque méthode développée, une série d’échantillons d’eau a été analysée pour toutes les matrices étudiées. La quantification des hormones stéroïdiennes a permis de rendre compte des niveaux de concentrations retrouvés dans l’environnement. Une étude saisonnière d’un cours d’eau a également été réalisée durant quatre saisons (hiver, printemps, été et automne) afin d’évaluer les éventuelles variations saisonnières en termes d’occurrence et de concentration. / It is now admitted that many substances such as endocrine disruptors are released daily into the environment. This process can be of natural origin but is predominantly linked to human activity. Endocrine disruptors originate from numerous fields: medicine, agriculture, cosmetics, and the food industry, to name a few. Steroid hormones belong to this wide array of compounds. A significant number of human diseases and behavioral and physiological changes in both humans and aquatic life have been attributed to the use and chronic release of these endocrine disruptors. The effects of such a cocktail of substances are difficult to understand and evaluate. To date, the synergistic mechanisms or the potential cumulative effects are not well known. It remains essential to develop an approach focused on the prevention and the study of contamination levels with one key word in mind: precaution.
In this context and aiming to detect steroid hormones in tap water, surface water and wastewater at trace levels, new analytical methods have been developed within the framework of this project. The first method developed is based on high performance liquid chromatography (HPLC) coupled with tandem mass spectrometry (MS / MS). LC-MS/MS hyphenation involved using an electrospray ionization source at atmospheric pressure with heating element (H-ESI). Pre-concentration and purification of the samples were executed by on-line solid phase extraction (on-line SPE). The validated method presents several advantages: reproducibility, automation, minimum analysis time, reduced logistics and above all, detection limits ranging from 0.10 ng·L-1 to 7.5 ng·L-1 considering the different matrices studied.
The second approach proposed herein is based on the development of an analysis method allowing lower detection limits compared to the previous workflow. The same detection method was used, but a modification was made to the sample extraction and purification. Allowing for greater pre-concentration than online SPE, manual SPE (off-line SPE) was used in this method. Depending on the particular matrix, the extraction step allowed to reach adequate detection limits for the analysis of environmental aqueous samples: 0.010 ng·L-1 up
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to 6.0 ng·L-1 from the matrix-free sample to the most complex matrices. The use of an automated system also made it possible to make the extraction step robust and reproducible.
The analysis of the dissolved phase of water samples cannot be sufficient to understand and comprehensively assess the contamination of aquatic environments. The particulate phase in suspension in the water column (SPM) was also studied. The extraction method was optimized and validated. Coupled with the previous method of analysis, it was possible to quantify the steroid hormones attached to suspended materials. The obtained detection limits ranged from 0.10 ng/g to 3.0 ng/g dry weight.
For each developed method, dissolved phase samples were analyzed for all the studied matrices (tap water, surface water and wastewater). Quantification of steroid hormones allowed the comprehension of concentration levels found in the environment under usual discharge conditions in multiples matrices. A seasonal study of a watercourse was also carried out during the winter, spring, summer and fall seasons to observe possible seasonal variations in terms of occurrence and concentration.
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Développement et évaluation d’une méthode LC-MS/MS pour l’analyse de résidus de tir en criminalistique/Development and assessment of a LC-MS/MS method for the analysis of gunshot residues in criminalisticsLaza, Désiré 16 February 2007 (has links)
Ce travail de thèse rentre dans le cadre d’un projet de recherche appliquée mené à l’Institut National de Criminalistique et de Criminologie s’intitulant « développement d’un système intégral de détection et d’identification de résidus de tir » visant à doter le laboratoire de balistique chimique d’un outil performant pour la recherche et la caractérisation des résidus de tir aussi bien inorganiques qu’organiques. Comme nous l’expliquons dans le chapitre 1, l’analyse des résidus de tir est aujourd’hui essentiellement basée sur la mise en évidence par microscopie électronique à balayage des particules métalliques provenant de l’amorce. Cette pratique a des limites. Introductif, ce chapitre met en lumière la relation entre criminologie et criminalistique, donne un aperçu de la classification des armes et décrit les relations entre les armes de poing, les munitions, les résidus de tir et la criminalistique. La motivation de l’analyse de résidus organiques et plus particulièrement des stabilisants pour poudres propulsives y est aussi expliquée. Le but principal de ce travail étant le développement d’une méthode d’analyse des stabilisants par spectrométrie de masse en tandem couplée à la chromatographie liquide à haute performance (LC-MS/MS), ce premier chapitre aborde de façon détaillée le principe de fonctionnement d’un spectromètre de masse quadripolaire, qu’il soit avec simple quadripôle ou en tandem, et traite avec une attention particulière les aspects relatifs à la production d’ions, l’acquisition des données et la détection des ions.
Le chapitre 2 est consacré aux résultats et discussions. Comme point de départ de tous les travaux ultérieurs, l’optimisation du fonctionnement du spectromètre et plus particulièrement la détermination des « ions précurseurs » et des « ions produits » y est traitée en détails. De plus, l’étude de la fragmentation des ions précurseurs y occupe une place prépondérante et conditionne l’établissement d’une méthode de détection et d’acquisition des données. Dans ce même chapitre sont successivement traités la mise au point de la méthode chromatographique pour l’analyse des stabilisants par LC-MS/MS, le couplage LC-MS/MS, la collecte et préparation des échantillons, dont l’extraction sur phase solide (SPE). Disposant des procédures de traitement des échantillons et d’une méthode LC-MS/MS, il nous a été possible de mener l’étude de faisabilité de l’analyse des stabilisants dans les échantillons prélevés sur les mains d’un tireur. Cette étude fait l’objet d’une proposition de publication jointe en annexe. Pour être exploitable en criminalistique, ce travail est complété par une étude sur les fréquences d’observation des stabilisants pour poudres propulsives sur les mains des non-tireurs.
L’ensemble des résultats nous permet de dresser un bilan et proposer des perspectives décrites dans le chapitre 3. A cet égard, nous proposons de poursuivre les essais relatifs aux tests de persistance des résidus de stabilisant sur les mains des tireurs et d’entamer une étude sur la caractérisation des résidus de tir de la nitrocellulose. Du point de vue de l’exploitation des acquis de ce travail, nous suggérons que les méthodes et procédures développées soient mises à l’épreuve dans les affaires nécessitant l’analyse des prélèvements effectués sur les vêtements d’un suspect ou d’une victime. Cette mise à l’épreuve permettra de comparer l’efficacité de la méthode LC-MS/MS à celle de la technique SEM/EDX habituellement utilisée.
Le chapitre 4 est consacré aux matériels et méthodes détaillant notamment les procédures de collectes et de traitement des échantillons, les paramètres de fonctionnement du spectromètre de masse et les méthodes analytiques.
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This thesis deals with a research project entitled "Development of an integral system of detection and identification of gunshot residues”, carried out at the Belgian National Institute of Criminalistics and Criminology (NICC). This project aims at providing the Laboratory of Chemical Ballistics, a powerful tool to detect and identify organic gunshot residues. For instance, the analyses of gunshot residues is presently performed mainly for characterizing metallic particles originating from the primer, using scanning electron microscopy coupled to energy dispersive X-ray microanalysis (SEM-EDX). However this technique has its limits and the goal of the thesis was the development of a method for the analysis of the stabilizers (and their derivatives) present in propellant powders with the use of tandem mass spectrometry coupled to high performance liquid chromatography (LC-MS/MS).
The introduction highlights the relations between Criminology and Criminalistics; it gives an outline of the classification of weapons, and describes how handguns, ammunitions, gunshot residues and Criminalistics can be linked when investigating criminal cases. The motivation of the analysis of organic gunshot residues and in particular the propellant powder stabilizers is also explained.
Chapter 1 deals in detail with the working principle of a quadrupole mass spectrometer, whether it is with a single quadrupole or composed of a tandem mass spectrometer. Important aspects connected with the ion production, the data acquisition and the ion detection are also considered.
Chapter 2 presents the results and discussions. It begins with the optimization of the operating conditions of the spectrometer, and focuses more specifically on the determination of “precursor ions" and "daughter ions”. The study of the precursor ion is more important because it is required for the choice of parameters involved in the data acquisition mode. The development of a liquid chromatography (LC) method and the procedures for collecting and preparing the samples are explained. Moreover, Chapter 2 summarizes the results of a feasibility study of the analyses of stabilizers in samples collected from the hands of a shooter. This study was published in a peer reviewed journal [1]. A complementary study on the frequencies of observation of stabilizers on the hands of non-shooter persons is reported at the end the Chapter.
The results allow also proposing perspectives which are described in Chapter 3. In this respect, the characterization of nitrocellulose residues and the study of the persistence of stabilizer residues on the hands of shooters should be undertaken. From the practical point of view, the developed methods and procedures should be tested in real cases which involve the analyses of the samples taken from the clothing of suspects and/or victims. These tests should allow an assessment of the LC-MS/MS method compared to the efficiency of the SEM/EDX technique currently used.
Chapter 4 is dedicated to the materials and methods; the sample collection and treatment procedures, as well as the working parameters of the mass spectrometer and the analytical methods are explained in detail.
[1]. Désiré Laza, Ph.D.; Bart Nys, Ph.D.; Jan De Kinder, Ph.D.; Andrée Kirsch - De Mesmaeker, Ph.D.; and Cécile Moucheron, Ph.D. Development of a Quantitative LC-MS/MS Method for the Analysis of Common Propellant Powder Stabilizers in Gunshot Residue. J. Forensic Sci, July 2007, Vol. 52, N° 4, 842-850.
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