Capillary electrochromatography (CEC) is a major capillary electrophoresis (CE) mode that have been interfaced to mass spectrometry (MS) for sensitive and selective analysis of chiral compounds. This research expands CEC applications in cancer biomarker and chiral CE analysis. Chapter 1 is a review of liquid chromatography-mass spectrometry (LC/MS), gas chromatography-mass spectrometry (GC/MS), and capillary electrophoresis mass spectrometry (CE/MS) for analysis of metabolites in prostate cancer diagnostics and therapies. In this chapter, a literature survey was performed within the databases PubMed, 4 Caplus/Webline and Web of Sciences. A total 17 studies reporting on various analytical platforms for metabolite identification in prostate cancer research, which often include case-control comparison were identified and reviewed. Chapter 2 described the analysis of metabolite biomarkers in prostate cancer tissues by capillary electrochromatography mass spectrometry. In this chapter, a capillary CEC–MS/MS method was developed for the simultaneous determination and separation of eight proofs of concept (POC) metabolites (betaine, malate, proline, N-acetyl aspartate, N-acetylglucosamine, uracil, xanthine, and alanine) as potential prostate cancer diagnostic markers. A polymeric monolith column with a hydrophilic crosslinker and strong anion-exchange mixed-mode has been fabricated by an in situ copolymerization of vinyl benzyl trimethylammonium chloride, and bisphenol A glycerolate dimethacrylate (BisGMA) in the presence of methanol and dodecyl alcohol as porogens and AIBN as initiator. After CEC separation, samples were analyzed by a triple–quadrupole mass spectrometer operated in positive ion mode. After optimization, the data showed that the CEC-MS/MS method using monolithic column achieved a much better chromatographic selectivity compared to coated columns and increased sensitivity than bare fused silica column The effect of mobile phase pH, ACN percentage and additive were studies. Under the optimum mobile phase conditions, this method was carried out to separate and detect eight metabolites in the biopsy sample. The LOD for the metabolites is between 50nM-100nM. This method has successfully used to examine patients’ prostate cancer with an accuracy of 95%. Chapter 3 demonstrates Insights into Chiral Recognition Mechanisms in CEC using linear salvation energy relationship. By varying the linker (amide and carbamate), head group (alanine, leucine, and valine) and chain length (C8, C10 and C12) of the amino acid bound surfactants; monolithic column was made to ultimately understand the factors governing chiral stationary solid phase. Through the comparison of system parameters, we can see that surfactant head group, linker and chain length affect the separation of achiral and chiral compounds. Also, with the same type surfactant, data was presented to show how the trend of LSER parameters and how it affects separation between in CEC. This study showed the predictive capability of LSER to understand the aforementioned intermolecular processes controlling retention and by doing so, be able to quantitatively predict the experimental conditions to achieve an acceptable chiral separation.

<p>This thesis describes the application of multivariate methods in a novel approach to the formulation of tablets for direct compression. It begins with a brief historical review, followed by a basic introduction to key aspects of tablet formulation and multivariate data analysis. The bulk of the thesis is concerned with the novel approach, in which excipients were characterised in terms of multiple physical or (in most cases) spectral variables. By applying Principal Component Analysis (PCA) the descriptive variables are summarized into a few latent variables, usually termed scores or principal properties (PP’s). In this way the number of descriptive variables is dramatically reduced and the excipients are described by orthogonal continuous variables. This means that the PP’s can be used as ordinary variables in a statistical experimental design. The combination of latent variables and experimental design is termed multivariate design or experimental design in PP’s. Using multivariate design many excipients can be included in screening experiments with relatively few experiments.</p><p>The outcome of experiments designed to evaluate the effects of differences in excipient composition of formulations for direct compression is, of course, tablets with various properties. Once these properties, e.g. disintegration time and tensile strength, have been determined with standardised tests, quantitative relationships between descriptive variables and tablet properties can be established using Partial Least Squares Projections to Latent Structures (PLS) analysis. The obtained models can then be used for different purposes, depending on the objective of the research, such as evaluating the influence of the constituents of the formulation or optimisation of a certain tablet property.</p><p>Several examples of applications of the described methods are presented. Except in the first study, in which the feasibility of this approach was first tested, the disintegration time of the tablets has been studied more carefully than other responses. Additional experiments have been performed in order to obtain a specific disintegration time. Studies of mixtures of excipients with the same primary function have also been performed to obtain certain PP’s. Such mixture experiments also provide a straightforward approach to additional experiments where an interesting area of the PP space can be studied in more detail. The robustness of a formulation with respect to normal batch-to-batch variability has also been studied.</p><p>The presented approach to tablet formulation offers several interesting alternatives, for both planning and evaluating experiments.</p>

The increasing mass and complexity of chemicals being produced and transported has resulted in more rigorous demands on both authorities as well as chemical-handling industries to assess the risks involved. The Environment-Accident Index (EAI), has been proposed as a planning tool created as an equation in which chemical properties (variables describing the chemical involved) are combined with site-specific properties (variables describing the accident site). The EAI is intended to facilitate assessment of the environmental effects related to chemical accident scenarios and hence assist the organisation of preventative programs. The main objective of the work described in this thesis was to evaluate, develop and improve the proposed EAI. The steps involved in the development process included I) evaluation of the feasibility of the EAI approach, II) selection of a representative and diverse set of chemical accidents to be used in the development III) the use of questionnaires and expert judgements to develop response values for environmental effects of a chemical accident, and IV) to create a new EAI model using multivariate modelling (PLS). The EAI approach proved to be useful in the work to protect the environment in case of a chemical accident. A representative set of accidents was selected by means of statistical multivariate design (PCA) based on assembled data related to a set of 55 chemical accidents. The selection generated a set of accidents representing a diverse spectrum of chemical accident scenarios. To develop a measure of environmental effects of the chemical accidents i.e. responses, an expert panel was asked to judge their environmental effects (such as effects on animal life in the aquatic or terrestrial environment). The results showed that the judgements give a rough estimate of environmental effects that could be used as responses in the development of the EAI. The developed responses were then related to the chemical and site-specific properties to create a new EAI model. This resulted in a PLS-based EAI connected to a new classification scale. The advantages of the new EAI are that it can be calculated without the use of tables; it can estimate the effects for all included responses, and make a rough classification of chemical accidents according to the new classification scale. Finally, the new EAI is a more stable model than the previously proposed EAI, and it is founded on a valid base of accident scenarios, making its use for a variety of chemicals and situations more reliable since it covers a broader spectrum of accident scenarios. The new EAI can be expressed as a regression model to facilitate calculation of the index for people that do not have access to PLS. The highest priorities for further refining the new EAI in the future are: external validation of the EAI; further refinement of the formula’s structure; adjustment of the new classification scale; and real-life evaluation of the EAI.

This thesis describes the application of multivariate methods in a novel approach to the formulation of tablets for direct compression. It begins with a brief historical review, followed by a basic introduction to key aspects of tablet formulation and multivariate data analysis. The bulk of the thesis is concerned with the novel approach, in which excipients were characterised in terms of multiple physical or (in most cases) spectral variables. By applying Principal Component Analysis (PCA) the descriptive variables are summarized into a few latent variables, usually termed scores or principal properties (PP’s). In this way the number of descriptive variables is dramatically reduced and the excipients are described by orthogonal continuous variables. This means that the PP’s can be used as ordinary variables in a statistical experimental design. The combination of latent variables and experimental design is termed multivariate design or experimental design in PP’s. Using multivariate design many excipients can be included in screening experiments with relatively few experiments. The outcome of experiments designed to evaluate the effects of differences in excipient composition of formulations for direct compression is, of course, tablets with various properties. Once these properties, e.g. disintegration time and tensile strength, have been determined with standardised tests, quantitative relationships between descriptive variables and tablet properties can be established using Partial Least Squares Projections to Latent Structures (PLS) analysis. The obtained models can then be used for different purposes, depending on the objective of the research, such as evaluating the influence of the constituents of the formulation or optimisation of a certain tablet property. Several examples of applications of the described methods are presented. Except in the first study, in which the feasibility of this approach was first tested, the disintegration time of the tablets has been studied more carefully than other responses. Additional experiments have been performed in order to obtain a specific disintegration time. Studies of mixtures of excipients with the same primary function have also been performed to obtain certain PP’s. Such mixture experiments also provide a straightforward approach to additional experiments where an interesting area of the PP space can be studied in more detail. The robustness of a formulation with respect to normal batch-to-batch variability has also been studied. The presented approach to tablet formulation offers several interesting alternatives, for both planning and evaluating experiments.

Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2016-09-06T16:08:00Z No. of bitstreams: 1 Lopes W A Tese de Doutorado IQ-UFBA 2007.PDF: 2585828 bytes, checksum: 5e4ecce83a58663cda34dce3a68a966c (MD5) / Approved for entry into archive by Vanessa Reis (vanessa.jamile@ufba.br) on 2016-09-08T10:48:19Z (GMT) No. of bitstreams: 1 Lopes W A Tese de Doutorado IQ-UFBA 2007.PDF: 2585828 bytes, checksum: 5e4ecce83a58663cda34dce3a68a966c (MD5) / Made available in DSpace on 2016-09-08T10:48:19Z (GMT). No. of bitstreams: 1 Lopes W A Tese de Doutorado IQ-UFBA 2007.PDF: 2585828 bytes, checksum: 5e4ecce83a58663cda34dce3a68a966c (MD5) / CNPq, FINEP, FAPESB e ANEEL / Os Hidrocarbonetos policíclicos aromáticos (HPA) são poluentes formados geralmente durante a combustão incompleta de petróleo e derivados, carvão mineral, biomassa e outros materiais orgânicos. São emitidos por diversas fontes naturais ou antrópicas e estão presentes na atmosfera, hidrosfera e litosfera. A atmosfera é o seu principal meio de transporte onde se encontram em fase vapor ou adsorvidos em material particulado. Em centros urbanos, sua emissão está associada principalmente aos veículos automotores, movidos a diesel e gasolina. Os HPA e seus derivados, por exemplo, os nitro-HPA e oxi-HPA, são agentes cancerígenos e/ou mutagênicos, daí a importância de estudos sobre a sua presença na atmosfera e em outras matrizes ambientais, sobre a reatividade e atividades biológicas. Neste trabalho, foram determinadas as concentrações atmosféricas para 16 HPA considerados como poluentes prioritários pela agência de proteção ambiental dos Estados Unidos da América (U. S. EPA), em amostras de material particulado atmosférico (MPA), usando o método de CG-EM com monitoramento de íons selecionados. As amostras de MPA foram coletadas em amostradores de grande volume (Hi-vol) e, em seguida, foram extraídas usando a técnica de sonicação e uma solução de acetonitrila e diclorometano (3:1) como solvente. Os extratos foram pré- concentrados (10/1) e em seguida analisados por CG-EM/SIM. Com o objetivo de assegurar uma boa separação dos 16 HPA, no menor tempo de análise, foi utilizado o planejamento multivariado para estabelecer as condições de programação de temperatura do forno (aquecimento da coluna). O processo de otimização foi realizado por meio do planejamento fatorial fracionário e através do planejamento do tipo Box-Behnken, sendo avaliados os seguintes fatores: temperatura inicial (oC), velocidade de elevação da temperatura N° 1 (°C.min-1), temperatura intermediária (oC), velocidade de elevação da temperatura N° 2 (°C.min-1) e temperatura final (oC). As condições otimizadas para a separação dos 16 HPA foram estabelecidas em: 70 °C (2 min) ? 200 °C (30 °C/min, 5 min) ? 300 °C (5 °C/min, 1,67 min). O tempo total da análise, com uma boa separação dos 16 analitos, ficou em 33 minutos. A validação da técnica de CG-EM, no modo SIM, apresentou resultados considerados satisfatórios para a repetitividade da resposta do detector, repetitividade do tempo de retenção, e linearidade das curvas de calibração. Os limites de detecção foram estabelecidos entre 0,13 e 0,34 ng mL-1 (área) e 0,18 e 0,72 ng mL-1 (altura de pico) e os limites de quantificação entre 0,38 e 1,04 ng mL-1 (área) e entre 0,61 e 2,39 ng mL-1 (altura de pico). As amostras ambientais de MPA foram coletadas em quatro diferentes locais, apresentando os seguintes resultados: i) Estação da Lapa (Salvador, BA) - Os HPA presentes em concentrações mais altas foram o criseno (CRI), pireno (PIR) e benzo[b]fluoranteno (BbF), apresentando concentrações médias de respectivamente 2,62, 1,32 e 1,30 ng m-3, e perfil compatível com emissões de veículos movidos a diesel; ii) Porto de Aratu (Candeias, BA) - Os HPA presentes em maiores concentrações foram o benzo[b]fluoranteno (BbF), benzo[g,h,i]perileno (BgP) e Indeno[1,2,3- c,d]pireno (IND), apresentando concentrações médias de respectivamente 2,53, 1,22 e 1,12 ng m-3 (AGV-PTS) e 1,74, 0,82 e 0,73 (AGV MP10); iii) Ilha de Maré, (Salvador, BA) – os valores mais altos foram observados para o benzo[b]fluoranteno (BbF), benzo[b]fluoranteno (BkF) e benzo[g,h,i]perileno (BgP), apresentando concentrações médias de respectivamente 1,62, 0,73 e 0,72 ng m-3; iv) Cidade Universitária da USP (São Paulo, SP) - Os HPA que apresentaram maiores concentrações médias foram o benzo[b]fluoranteno (BbF), criseno (CRI) e o benzo[g,h,i]perileno, com os valores de, respectivamente, 0,93, 0,50 e 0,49 ng m-3. Os resultados foram avaliados em termos de perfil das concentrações, prováveis fontes de emissões e, em alguns casos, por comparação com análises anteriores. / Polycyclic aromatic hydrocarbons (PAH) are ubiquitous pollutants that are emitted from several natural or anthropic sources and may be present in the atmosphere, hydrosphere and lithosphere. They usually originate during the incomplete combustion of petroleum and its derivatives, mineral coal, biomass and other organic materials. They are mainly transported in the atmosphere, being present either in the vapor phase or adsorbed in particulate material. In urban centers, emission is mainly associated with diesel- and gasoline-powered motor vehicles. Since PAH and derivatives, e.g. nitro-PAH and oxy-PAH, are carcinogenic and/or mutagenic agents, to study the effect of their presence in the atmosphere and in other environmental matrices on the biological activity and reactivity are of key relevance. In this study, the atmospheric concentrations of the 16 PAHs that are considered priority pollutants by the U.S. Environmental Protection Agency were evaluated in samples of atmospheric particulate material (APM), using gas chromatography / mass spectrometry with selected-ion monitoring mode (GC-MS/SIM). APM samples were collected in high-volume air samplers (Hi-vol) and then extracted under sonication with a solution of acetonitrile and dichloromethane (3:1) as a solvent. Extracts were pre-concentrated (10/1) and analyzed by GC-MS/SIM. In order to assure an adequate separation of the 16 PAHs, in the shortest analysis time, a multivariate design was used to set the conditions of the oven temperature program (column warming). The optimization process was carried out using factorial fractional design and Box-Behnken design. The following factors were evaluated: initial temperature (ºC), temperature rate N°1 (ºC.min-1), intermediate temperature (ºC), temperature rate N°2 (ºC.min-1) and final temperature (ºC). The optimized conditions for the separation of the 16 PAH were set at: 70 ºC (2 min) → 200 ºC (30 ºC/min, 5 min) → 300 ºC (5 ºC/min, 1.67 min). Total analysis time, with an adequate separation of the 16 analytes was 33 minutes. Validation of GC-MS in the SIM mode rendered satisfactory results for repeatability of detector response, repeatability of retention time, and linearity of calibration curves. Detection limits were established between 0.13 and 0.34 ng mL- 1 (area) and 0.18 and 0.72 ng mL-1 (peak height). Environmental samples of PMA were collected at four different locations, with the following results: i) Lapa Bus Station (Salvador, BA) - The PAH with the highest concentrations were crysene (CRY), pyrene (PYR) and benzo[b]fluoranthene (BbF), with mean concentrations of 2.62, 1.32, and 1.30 ng m-3, respectively, suggesting a profile compatible with diesel vehicle emissions; ii) Port of Aratu (Candeias, BA) – The PAH with the highest concentrations were benzo[b]fluoranthene (BbF), benzo[g,h,i]perylene (BgP) and indeno[1,2,3-c,d]pyrene (IND), with mean concentrations of 2.53, 1.22, and 1.12 ng m-3 (TSP) and 1.74, 0.82 e 0.73 (PM10), respectively; iii) Ilha de Maré, (Salvador, BA) – The PAH with the highest concentrations were benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF) and benzo[g,h,i]perylene (BgP), with mean concentrations of 1.62, 0.73 e 0.72 ng m-3, respectively; iv) University of São Paulo (São Paulo, SP) - The PAH with the highest mean concentrations were benzo[b]fluoranthene (BbF), chrysene (CRI) and benzo[g,h,i]perylene (BgP) with values of 0.93, 0.50 and 0.49 ng m-3, respectively. The results were evaluated with respect to concentration profile, probable emission sources and in some cases, were compared to prior analyses.

<p>Diss. (sammanfattning) Umeå : Umeå universitet, 1990, härtill 5 uppsatser.</p> / digitalisering@umu.se