Orientadores: Marcos José Salvador, Inés Joekes / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-24T13:48:04Z (GMT). No. of bitstreams: 1 Pavani_Matheus_M.pdf: 3408518 bytes, checksum: bdb62efa906a9a04de3a371f12ecd0f0 (MD5) Previous issue date: 2014 / Resumo: A fragrância de um produto cosmético é um aspecto importante para determinar seu desempenho. É crescente o emprego de produtos naturais, bem como de fragrâncias encapsuladas na indústria cosmética. Entretanto, há escassos estudos descrevendo o perfil de liberação de fragrâncias a partir de matrizes complexas, muito menos a partir de cabelos. Este trabalho investigou a interação de uma fragrância livre ou encapsulada em cabelos virgens caucasianos. Óleo essencial de capim-limão (Cymbopogon citratus DC. Stapf), livre ou encapsulado, foi empregado como fragrância em formulações de xampu e condicionador sem enxágue. O processo de encapsulação deu-se por meio de polimerização in situ da resina de melamina-formaldeído, variando-se parâmetros reacionais como velocidade de agitação, acidificação do meio e teor de óleo essencial. Os perfis de liberação da fragrância proveniente de mechas de cabelo, tratadas com as formulações obtidas, foram tomados ao longo do tempo (0 a 12 h), com amostragem por microextração em fase sólida (SPME) e análise por cromatografia gasosa acoplada à espectrometria de massas (CG-MS). A liberação das substâncias da fragrância na forma livre variou em função do tipo de formulação cosmética (xampú ou condicionador sem enxágue). Neste caso, a persistência delas na fibra capilar se correlacionaou com seus valores de coeficiente de partição óleo-água (logP). Micropartículas esféricas (dH = 9 ± 1 µm) e rendimento de processo de 86 % foram obtidos com decaimento lento de pH aliado a agitação vigorosa durante a reação de formação. Estas partículas promoveram liberação sustentada para os constituintes linalol e citral (12 e 2 vezes mais duradoura em relação à forma livre, respectivamente), mostrando um aumento da persistência da fragrância encapsulada quando inserida em formulação sem enxágue, e modificando as forças de interação cabelo¿fragrância / Abstract: Fragrance plays an important role in the performance of a cosmetic formulation. The use of natural products in the cosmetic industry as well as encapsulated fragrances is growing. However, there are few studies describing the release profile of fragrances from complex matrices, much less from Human hair. This work investigates the interaction of a fragrance composition (free or encapsulated) with un-treated Caucasian hair. Lemongrass essential oil (Cymbopogon citratus DC. Stapf) was employed as fragrance in rinse-off shampoo or leave-on formulations. Encapsulation was performed by in situ polymerization of melamine and formaldehyde monomers, changing reaction parameters such as stirring rate, pH decay, and essential oil content. Fragrance release profiles from the hair tresses treated with the abovementioned formulations were acquired over the time (0 to 12 h) with a solid phase microextraction (SPME) device, and analyzed by gas chromatography-mass spectrometry (GC-MS). The release of free form fragrance constituents depended on the type of cosmetic formulation (shampoo or leave-on), but its persistence on hair fiber was correlated with its oil-water partition coefficient (logP) value in both cases. Spherical microparticles (dH = 9 ± 1 µm) and 86 % yield were obtained with slow pH decay combined with vigorous stirring during the encapsulation process. Sustained release of the fragrant components linalool and citral (12 times and twice longer-lasting compared to the free form, respectively) was found, showing an increased persistence of the encapsulated fragrance when inserted in the leave-on formulation and changing perfume¿hair interaction / Mestrado / Fármacos, Medicamentos e Insumos para Saúde / Mestre em Biociências e Tecnologia de Produtos Bioativos

Please read the abstract in the section front of this document / Dissertation (MSc)--University of Pretoria, 2007. / Chemical Pathology / unrestricted

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This study focuses on a general method that has been developed for the identification of both polar- and nonpolar pesticidespolar pesticides in a known solution from EPA 8151 Herbicide acid mix by Merck including the ordered non-polar pesticide Prosulfocarb. The EPA-solution contains 16 analytes that has been completely identified when derivatized and spiked in acetone. The solution has also been spiked in blood samples, resulting in five calibration solutions in the range of 0,01 – 2,5 µg/g, followed by quantification. Identification of dinoseb and bentazone, spiked in blood, failed whereas the remaining 145 analytes were identified. The method uses headspace (HS) solid phase microextraction (SPME) in combination with gas chromatography (GC) with mass spectrometry (MS) in both scan and selected ion monitoring mode. A standard extraction- and derivatization procedure has been performed for the analysis of alcohols, phenols, and carboxylic acids with help from a protocol regarding the analysis of ethylene glycol in blood. Samples were introduced on the column with splitless injection where 1 µl were injected with an injector temperature of 250oC. Effective separations were achieved by using GS-GasPro PLOT-column (30 m x i.d. 320 µm x df 0 µm) in combination with a temperature programme that started at an initial temperature of 80oC (1 min) that increased by 10oC/min up to 280oC (1 min). The limit of detection (LOD) for the pesticides, spiked blood, were 0,01 – 2,5 µg/g where the lowest limit of 0,01 µg/g meant difficult identification whereas a greater identification was made at 0,05 µg/g. No identification was succeeded for the most polar substances in the forms of amines and amides in combination with carboxylic acid. Identification was however made for the less polar pesticides in the forms of alcohols, phenols, and carboxylic acids. The method must be further developed to identify the highly polar pesticides in different chemical classes. The current method can be used in occurring intoxications and in autopsy cases.

This research is done to determine the distribution of flavonoids in diverse varieties of onions (commercial and wild onions). Reflux extraction method was done on dried onions and the abstracts were analyzed subsequently by high performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GCMS). Statistical calculations were done to see if there are significant differences in the varieties of onions studied from the chromatographic profiles obtained. The chromatograms obtained were patterned using visual observations, scatter plot study, correlation co-efficient, and ANOVA to evaluate the significant difference of the distribution of flavonoids in varieties of onions. The organic white onions seem to have closer flavonoids profile to that of natural wild onions with a corelation coefficient of 0.99 from HPLC data and 0.88 from the GCMS data. The ANOVA results also support these conclusions. However, natural wild onions tend to have more constituents that can be beneficial.

Rapid, portable detection of biological threat agents such as Bacillus anthracis endospores (“spores”) is extremely important given the real and perceived threats of bioterrorism. Gas chromatography-mass spectrometry (GC-MS) is an excellent general means for chemical detection, although special sample preparation and specialized equipment are required to employ GC-MS for detecting biological agents such as spores in the field. A GC sample introduction probe consisting of a helical wire that can be retracted inside a syringe needle, called a coiled wire filament (CWF), was employed as a simple, passively-heated means to introduce the mixture of spores plus reagents for thermochemolysis methylation (TCM) into the pre-heated GC inlet. There, reactions between spore biomarkers and the TCM reagent mixture occur between 250-290°C. At these conditions, monomethyl sulfate salt mixtures are convenient and efficient TCM reagents for the rapid conversion of a key unique spore biomarker, dipicolinic acid (DPA), to its dimethyl ester (Me2DPA). By this process, Me2DPA yields from spores were quantitatively assessed for different combinations of tetramethylammonium hydroxide (TMA+OH−), sodium hydroxide (Na+OH−), and hydrogen monomethyl sulfate (H+MeSO4−). The best reagent mixture was found by varying the combinations of the ions within the neutral or basic system containing TMA+, Na+, OH−, and MeSO4− according to a novel scheme for design of experiments termed ionic mixtures design of experiments (IMDOE). A combination of the above ions was found that is near-quantitative in its methylation of DPA to Me2DPA; this mixture contained a 1:3:1:3 mole ratio of TMA+:Na+:OH−:MeSO4−. This yield of Me2DPA was approximately a ten-fold increase over the best performance observed at the same conditions with tetramethylammonium hydroxide alone, the TCM reagent widely-used for GC. The reactions involving MeSO4− and TMA+ as methylating reagents, plus relevant hydrolysis and methylation reactions involving acid and base plus water and methanol, were investigated. An overall model is presented and mechanisms are proposed for reasons why basic mixtures of MeSO4− salts are more effective in methylating DPA compared to TMA+ salts at the conditions employed.

A simple method was developed for detection and differentiation of five Tier 1 bacterial agents, including Bacillus anthracis, Francisella tularensis, Yersinia pestis, Burkholderia pseudomallei and Burkholderia mallei as well as their closely related near neighbors by gas chromatography-mass spectrometry (GC-MS). Generally, different classes of compounds can be used as biomarkers for biowarfare agent detection, including nucleic acids (i.e., DNA or RNA), proteins (i.e., antibodies), carbohydrates (i.e., sugars), lipopolysaccharides, lipids (i.e., fatty acids) and small molecules. One-step thermochemolysis (TCM) was developed to provide GC-MS detectable biomarker signatures, including sugars, fatty acids and small molecules. Solid phase micro-extraction (SPME) was used for biomarker extraction, concentration and introduction into the GC-MS. Statistical algorithms were constructed using a combination of biomarkers for the five agents, which were robust against different growth conditions (medium and temperature). A general GC-MS temperature program was developed for all five Tier 1 bacteria. The total analysis time, including TCM, SPME extraction and GC-MS, is approximately 40 min. The total-ion chromatograms are very different for the five species. The final goal of this research was to develop an accurate, fast, simple, robust and automated method for field application. Therefore, an automated sample preparation system was designed, constructed and tested. The system automatically controls the movement of sample vials from one position to another, crimping of septum caps onto the vials, precise delivery of reagents and TCM reaction times and temperatures. The specific operations of introduction of sample vials, SPME sampling, injection into the GC-MS system and ejection of used vials from the system were performed manually in this study, although they can be integrated into the automated system. Manual SPME sampling is performed by following visual and audible signal prompts for inserting the fiber into and retracting it from the sampling port. A rotating carousel design allows for simultaneous sample collection, reaction, biomarker extraction and analysis of sequential samples. Bacillus species were used to test this autoreactor, and 96% of the samples were correctly identified using a statistical algorithm. This research applies not only to the rapid identification of Tier 1 agents after a biological attack, but should also benefit clinical diagnosis, which is essential to effective treatment.

This study provides chemical confirmation for the use of resinous plant exudates in mortuary contexts in Roman Britain. Analysis of amorphous masses, adhering residues and grave deposits using gas chromatography-mass spectrometry has revealed terpenoid biomarkers in sixteen inhumation and two cremation burials. The natural products characterized include European Pinaceae (conifer) resins, Pistacia spp. (mastic/terebinth) resins from the Mediterranean or the Levant and Boswellia spp. (frankincense) gum-resins from southern Arabia or eastern Africa. In addition, traces of a balsamic resin, probably Liquidambar orientalis, have been identified. A correlation between the use of these exotic exudates and interment in substantial, often multiple, containers with high-quality textiles and grave goods was observed. Theoretical consideration of this imported rite illuminates the multiplicity of roles played by resins/gum-resins in the mortuary sphere. The material properties of these highly scented substances speak to the biological reality of the decomposing body and to the socially constructed identity of the individual. On a practical level, they acted as temporary preservatives and masked the odour of decay. As social signifiers, they denoted the status of the deceased and promoted remembrance through conspicuous consumption and sensory impact. Encoded with ritual meaning, they purified the body and facilitated the final rite of passage to the afterlife. The recovery of these resinous traces provides us with new insights into the treatment of the body in the Roman period and establishes fresh links between the remote province of Britannia and the remainder of the Empire. / Arts and Humanities Research Council (AHRC). / Vol. II, which contains supplementary material files, is not available online.

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