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A Ciência Forense é uma área multidisciplinar, que usa do conhecimento científico para a investigação de questões penais e cíveis. Dentro de suas mais diversas áreas, a Toxicologia e a Documentoscopia Forense necessitam do auxílio de métodos analíticos, como a cromatografia, a espectrometria de massas e a análise multivariada, para a análise de compostos diversos. Em Toxicologia Forense, novos métodos para a detecção das drogas de abuso anfetamina, metanfetamina, cocaína, cetamina, mitraginina e canabinoides (THC e CBD) foram desenvolvidos utilizando coleta de fluido oral em dispositivos de dried oral fluid spots (DOFS) em papel filtro, seguido de extração líquido-líquido e análise por LC-MS/MS. Enquanto que para cinco drogas de abuso foi realizada a validação de um método quantitativo, para os canabinoides foram encontradas dificuldades na extração do papel filtro, e foi proposto um método qualitativo. Ainda, foi realizada uma revisão bibliográfica a respeito dos métodos quantitativos para a análise de canabinoides em fluido oral. Na área da Documentoscopia Forense, uma nova metodologia não-destrutiva, de baixo custo e de fácil acesso, foi desenvolvida para a diferenciação entre marcas de canetas esferográficas azuis. Esse estudo envolveu a captura de imagens utilizando o aplicativo para celulares Photometrix PRO®, com posterior análise estatística multivariada, utilizando PCA, HCA e PLS-DA. Este método demonstra também a necessidade de que Peritos em Documentoscopia tenham conhecimentos de análise multivariada, para proceder com a correta interpretação dos resultados. Para valorizar o conhecimento das metodologias analíticas na análise de tintas de canetas, foram apresentadas duas revisões bibliográficas. A primeira objetivou a busca sistemática dos métodos analíticos já estudados para a diferenciação e para a datação de tintas de canetas esferográficas azuis e pretas. Foram encontrados diversos métodos cromatográficos, de espectroscopia, de espectrometria de massas e de análise multivariada. A segunda revisão buscou a abordagem dessas metodologias voltada para Peritos Brasileiros. Essa Tese de Doutorado destaca ainda a multidisciplinariedade das Ciências Forenses, bem como a necessidade da formação de recursos humanos adequada na Perícia Brasileira. Forensic Science is a multidisciplinary area, which uses scientific knowledge in judicial questions investigations. Among its many subareas, Forensic Toxicology and Documentoscopy demand the support of analytical methodologies for several different compounds’ evaluation, such as chromatographic methods, mass spectrometry and multivariate analysis. Inside Forensic Toxicology scope, new analytical methods were developed for different drugs of abuse detection (amphetamine, methamphetamine, cocaine, ketamine, mitragynine and cannabinoids THC and CBD), using oral fluid collection applied into dried oral fluid spots (DOFS), followed by liquid-liquid extraction and LC-MS/MS analysis. A quantitative method validation was proposed for all drugs, except for cannabinoids, which have shown difficulties in the filter paper extraction process. Therefore, a qualitative method validation is proposed for THC and CBD detection in DOFS. Considering this, a systematic review was conducted concerning cannabinoids quantitative analysis in oral fluid. In Forensic Documentoscopy, it was developed a new non-destructive methodology, of low-cost and easy access, to differentiate between blue ballpoint pen brands. This study used image capturing with Photometrix PRO®, an app for smartphones, followed by multivariate analysis (PCA, HCA and PLS-DA). This method emphasizes that Documentoscopy Experts need to understand multivariate analysis, so that they can proceed with adequate results interpretation. To highlight the need for analytical methodologies knowledge in pen inks analysis, two literature reviews are presented. The first one aimed to perform a systematic search for studied analytical methods used to differentiate or to date blue and black ballpoint pen inks. Several chromatographic, spectroscopy, mass spectrometry and multivariate analysis methods were found. Thus, the second review aimed to highlight the importance of those methods approaches for Brazilian Experts. Besides the technological advance achieved with new analytical methodologies, this Doctorate Thesis highlights Forensic Science as a multidisciplinary field, also reinforcing the need for adequate human resources in Brazil.

In this work, the influence of ink composition on the tribological properties of ballpoint pens has been examined with a view to improve writing smoothness and pen lifetime. Friction experiments were performed using a ball on plate tribometer in order to simulate the sliding contact of a ballpoint pen. Ballpoint pen ink is composed of various solvents, resins, friction modifiers, colorants. To determine the basic tribological properties of ballpoint pen ink, this study focuses on the investigating the influence of different ink compositions: solvents, resins, and phosphate on the tribological behavior. The worn surfaces of specimens from tribological tests using different ink compositions were analyzed by using Fourier-transform infrared spectroscopy. Tribological tests were performed on eight different lubricant compositions including: i) the solvents without additives ii) the solvents with the resins and iii) the solvents with the friction modifiers. The results showed that for Oil A the tribological properties were affected by the molecular weight of the resin and the addition of phosphate reduced the coefficients of friction. Similar results were not observed for Oil B. In addition, it was found that the ratio of the components of the base oil affects the tribological properties of ballpoint pen ink.

Documents are frequent targets of fraud and adulteration. Sometimes it is not enough to determine the document’s authenticity or authorship, but it is also necessary to demonstrate when the document was signed or written. Determining the age of a document, also known as ink dating analysis, is still a challenge for the forensic examiners. There are two main approaches for the dating of ballpoint pen inks: the static method, which is based on the characterization and identification of the ink composition and comparison to a reference collection, and the dynamic method, which involves the study of ink’s processes and alterations that occur with time, considering environmental aging factors such as light and humidity. This article aims to provide a comprehensive systematic review of the studies regarding ballpoint ink characterization and dating, in the last ten years. There are several methods, destructive and non-destructive, which are capable of characterizing and differentiating blue and black ballpoint pens that have shown applicability to the static approach. Regarding the dynamic dating methods, most studies quantified the loss of 2-phenoxyethanol (2-PE) solvent over time using GC-MS, or studied the dyes degradation through different methods. Although ink dating approaches offer relatively good accuracy, there is still more research to be done, such as the documents’ storage conditions evaluation, the influence of initial ink quantity variation between different pen brands and writing fists, and the type of paper.

No Brasil, peritos criminais e cientistas forenses frequentemente são solicitados a resolver diversos casos que requerem análise de tintas de canetas esferográficas, visando aos processos de envelhecimento das substâncias contidas nas tintas, como resinas, corantes e solventes, e na análise do papel, envelhecido com extratos vegetais. A datação dos lançamentos com canetas esferográficas em documentos pode ser realizada através da análise do teor de solventes e/ou da degradação dos corantes da tinta da caneta e diversos métodos são apresentados na literatura. O objetivo desta Tese foi estabelecer e validar metodologia de análise de tintas de canetas, especificamente dos corantes e solventes (em especial o 2-fenoxietanol (2-FE)), e a presença de extratos vegetais no papel (em especial a presença de cafeína), utilizando métodos de alta resolução como ESI-ORBITRAP (Ionização por Spray Eletrônico - Espectrometria de Captura de Íons de alta resolução) e CG/EM (Cromatografia em fase Gasosa acoplada a Detector de Massas), para acompanhar o comportamento de envelhecimento de traços de diversos tipos de canetas e estabelecer um padrão no Brasil, pela evaporação do 2-FE. Além dos métodos acima descritos, realizou-se análise de diversas canetas esferográficas em diversos tipos de papéis, utilizando IV-ATR (Espectroscopia no Infravermelho com Acessório de Refletância Total Atenuada) para estabelecer método de datação de manuscritos, usando Análise Estatística Multivariada. Em relação à detecção de cafeína em papéis embebidos em chá e café preto, o método de CG/EM foi eficiente e a otimização do método utilizando planejamento fatorial resultou na constatação de que o tipo e a gramatura do papel influenciam na absorção de cafeína, bem como o tipo de bebida cafeinada e a forma de aplicação da mesma no papel. O perfil de substâncias com massa exata de componentes da formulação das diversas canetas analisadas pelo Orbitrap, processados a partir de Análise de Componentes Principais (PCA) e Análise de Grupamento Hierárquicos (HCA) foi capaz de diferenciar com um grande poder de discriminação mesmo amostras de mesma marca de caneta, mas de modelos diferentes, ao mesmo tempo em que aproximou em grupos canetas de formulação semelhante. Na análise dos traços tintas de canetas aplicados em diversos tipos de papel, com IV-ATR, verificou-se que o método foi capaz de adquirir espectros principalmente das tintas, sem influência do papel, além disto, a análise estatística multivariada conseguiu agrupar diversas canetas por semelhança na formulação e diferenciar canetas de marcas diferentes. Nas análises realizadas com traços da mesma caneta com idades diferentes, a estatística multivariada (PCA e HCA) foi capaz de diferenciar traços com idades diferentes, e o destaque nesta conclusão foi que nos loadings das PCs para diversas canetas, observou-se o peso das absorções relativas ao 2-FE em canetas mais recentes (algumas até 1 ano de aplicadas). Baseando-se nos grupamentos formados pela HCA dos espectros de infravermelho das canetas recentemente aplicadas, escolheram-se algumas canetas representativas dos grupos, as quais foram analisadas em diversas idades, por CG/EM, com o objetivo de quantificar o 2-FE, até 3 anos de envelhecimento. O que se pode observar foi que o tipo de papel (branco ou reciclado) influenciou na concentração de solvente extraída para os traços de canetas envelhecidos 27 meses, embora não tenha influenciado no caso de traços recém aplicados, na maioria das canetas. As condições de armazenamento do papel com os traços de caneta também foram decisivas, uma vez que as amostras mantidas na luz e em temperaturas mais elevadas, após 27 meses apresentaram um teor de solventes muito menor que as amostras armazenadas no escuro com temperatura controlada. Observou-se que as canetas com quantidades iniciais maiores de 2-FE apresentaram a tendência a evaporar este solvente mais rapidamente. Embora as canetas após 3 anos possuam quantidades muito menores de 2-FE, muitas vezes sem diferença estatística das quantidades entre 27 e 18 meses, entre as diferentes marcas de canetas, as quantidades ainda apresentaram diferença estatística, portanto podem ocorrer concentrações diferentes de solventes entre canetas diferentes com a mesma idade. Todos os experimentos conduzidos durante a presente Tese proporcionaram um screening efetivo do comportamento das canetas, tanto em formulação de corantes, como de solventes, proporcionando uma bagagem de conhecimento acumulado sobre as canetas utilizadas no Brasil, para que estudos futuros possam padronizar estas técnicas objetivando resultados conclusivos e confiáveis para a determinação da cronologia de documentos questionados criminalmente, com aplicação imediata na prática real dos laboratórios forenses. Brazilian Forensic Scientists are frequently asked about ballpoint strokes chronology, and in the recent years, many methods have been developed on this subject, aiming to determine ink-aging processes. Ballpoint ink dating could be done through analysis of solvent content and degradation of inks. To increase the reliability of the results, the presence of plant extracts on papers can also be evaluated. Considering that, the aim of this thesis was to establish and validate a methodology for the analysis of pen inks, specifically dyes and solvents (in particular 2-phenoxyethanol), and the presence of plant extracts on paper (in particular the presence of caffeine) using high resolution methods such as ESI-ORBITRAP (Electrospray Ionization-High-resolution Ion Capture Spectrometry) and GC / MS (Gas-phase Chromatography coupled to Mass Detector) with the purpose of accompanying the aging behavior of traces of various types of pens and establish a pattern relative to Brazil, accompanying mainly the evaporation of 2-PE. In addition to the methods described above, a number of ballpoint pens were also analyzed in different types of papers, using IV-ATR (Infrared Spectroscopy with Total Attenuated Reflectance Accessory), also attempting to establish a method of dating a manuscript using Multivariate Statistical Analysis. Regarding the detection of caffeine in papers soaked in tea and black coffee, the GC / MS method was efficient and the optimization of the method using factorial design resulted in the finding that the type and weight of paper influence the absorption of caffeine as well as the type of caffeinated beverage and the form of application of the same on paper are also decisive for the identification of caffeine. The profile of substances with exact mass of formulation components of the various pens, analyzed by Orbitrap, processed from Principal Component Analysis (PCA) and Hierarchical Grouping Analysis (HCA), was able to differentiate with a great power of discrimination even samples of same brand of pen, but of different models, while at the same time approached in groups pens of similar formulation. Orbitrap was able to identify acid and basic dyes, in addition to other components of the formulation, which facilitated the differentiation between the pens. In the analysis of the ink traces of pens applied to various types of paper, with IV-ATR, it was verified that the method was able to acquire spectra mainly of the inks, without influence of the paper, besides, the multivariate statistical analysis managed to group several pens by similarity in the formulation and differentiate pens from different brands. In the analyzes performed with strokes of the same pen of different ages, the multivariate statistic (PCA and HCA) was able to differentiate samples with different ages, and the highlight in this conclusion was that in the loadings of the PCs for several pens, the weight of absorptions of 2-PE counted in newer pens (some up to 1 year of use); however in older pens (more than 2 years), 2-PE absorptions were no longer observed. Based on the groups formed by the HCA of the infrared spectra of the newly applied pens, some pens representative of the groups were chosen, which were analyzed at different ages by CG / MS, with the aim of quantifying 2-PE, until 3 years of aging. The determination of the evaporation profile of 2-PE with the time of these pens allowed an understanding of how the aging of the formulations commercialized in Brazil behaves. It can be observed that the type of paper (white or recycled) influenced the concentration of solvent extracted for pen strokes aged 27 months, although it did not influence the case of newly applied ones in most pens. The storage conditions of the stokes in paper were also decisive, since the samples kept in the light and at higher temperatures, after 27 months presented a much lower solvent content than the samples stored in the dark with controlled temperature. It was found that pens with initial amounts greater than 2-PE showed a tendency to evaporate this solvent more rapidly. A very important conclusion was that, although the pens after 3 years had much smaller amounts of 2-PE, often without statistical difference of the amounts present with 27 months or 18 months, among the different brands of pens, the quantities still presented difference statistic, so the identification of different pen formulations remains important even after 3 years, as different concentrations of solvents may occur between different pens at the same age. All experiments conducted during the present thesis have provided an effective screening of the behavior of the pens, both in dye formulation and solvents, providing an accumulated knowledge of the pens used in Brazil; so that future studies can standardize these techniques for conclusive and reliable results for the determination of the chronology of documents questioned criminally, with immediate application in the real practice of forensic laboratories.