Browsing by Author "Barreiros, Luísa"
Now showing 1 - 10 of 19
Results Per Page
Sort Options
- Acetonitrile adducts of tranexamic acid as sensitive ions for quantification at residue levels in human plasma by UHPLC-MS/MSPublication . Silva, Eduarda M. P.; Barreiros, Luísa; Fernandes, Sara R.; Sá, Paula; Ramalho, João P. Prates; Segundo, Marcela A.The quantitative analysis of pharmaceuticals in biomatrices by liquid chromatography coupled with electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) is often hampered by adduct formation. The use of the molecular ion resulting from solvent adducts for quantification is uncommon, even if formed in high abundance. In this work, we propose the use of a protonated acetonitrile adduct for the quantitative analysis of tranexamic acid (TXA) by LC-MS/MS. The high abundance of the protonated acetonitrile adduct [M + ACN + H]+ was found to be independent of source-dependent parameters and mobile phase composition. The results obtained for TXA analysis in clinical samples were comparable for both [M + ACN + H]+ and [M + H]+ , and no statistically significant differences were observed. The relative stability and structure of the [M + ACN + H]+ ions were also studied by analyzing probable structures from an energetic point of view and by quantum chemical calculations. These findings, and the studied fragmentation pathways, allowed the definition of an acetimidium structure as the best ion to describe the observed acetonitrile protonated adduct of TXA.
- Análise de resíduos de 5-fluorouracilo no exterior de bombas infusoras após realização de tratamento oncológico em ambiente domiciliárioPublication . Cardoso, Andreia; Barreiros, Luísa; Sá, Maria dos Anjos; Sousa, Eulália; Carvalho, Daniel; Correia, Patrícia; Moreira, FernandoPese embora os benefícios potenciais da administração infusional de 5-fluorouracilo (5-FU) em regime de domicílio, já existiram relatos de derrames e resíduos de 5-FU no exterior de bombas infusoras, que reforça a necessidade do desenvolvimento e aplicação de metodologia analítica que permita a sua deteção e quantificação (Chefchaouni et al., 2023).
- Apple fermentation: Valorization of surpluses from the fruit industryPublication . Ribeiro, Tatiana; Leitão, Mariana; García, Pablo; Barreiros, Luísa; Correia, Patrícia; Correia, Patrícia Carla dos Santos CorreiaFermentation is an anaerobic process in which sugars are converted into alcohol by bacterial enzymes or into lactic acid by yeasts. Apple is rich in vitamins and phytochemicals, mainly flavonoids, and it is responsible for antioxidant action. Apples that are unsuitable for fresh use or of inappropriate commercial size are not valued in the market, as they often do not have the physical characteristics the consumer appreciates and are therefore rejected. Furthermore, in industries and fruit processing, high amounts of waste are generated. Study possibilities for valorizing apple waste through fermentation, combining the circular and sustainable economy concepts. Local producers, processing industries, and commercial areas were contacted to establish collaborations and test different apple fermentation conditions, varying the part of the fruit used. Flasks with apple and water were placed in the oven at 30 ◦C, samples were collected every 24 h, and the pH was measured. The fermented products were analyzed to evaluate their antimicrobial activity, measuring the inhibition halo for Escherichia coli, Staphylococcus aureus, Bacillus cereus, Pseudomonas aeruginosa, Staphylococcus epidermidis, and Candida albicans. The most promising was the test with only apple pulp, since it was under these conditions that a greater inhibition halo was recorded compared to tests with combinations of pulp, peel, seed, and stem. Fermented apple pulp demonstrated greater activity in the sensitivity test for Staphylococcus aureus, Bacillus cereus, Pseudomonas aeruginosa, and Staphylococcus epidermidis. Fermented apple appears to have antimicrobial activity against several species. It is necessary to repeat the tests and analyze the intermediate fermentation times. It would be interesting to vary the state of division of the fruit as well as to carry out biostimulation tests and bioinoculation. As a future project, in addition to analyzing antimicrobial activity, it is intended to identify fermented products, using UV/VIS spectrophotometry and HPLC.
- Assessing the differences of two vineyards soils’ by NIR spectroscopy and chemometricsPublication . Machado, Sandia; Barreiros, Luísa; Graça, António R.; Madeira, Manuel; Páscoa, Ricardo N. M. J.; Segundo, Marcela A.; Lopes, João A.Soil properties influence greatly the status of vine plants which consequently influences the quality of wine. Therefore, in the context of viticulture management, it is extremely important to assess the physical and chemical parameters of vineyards soils. In this study, the soils of two vineyards were analysed by near-infrared (NIR) spectroscopy and established analytical reference procedures. The main objective of this study was to verify if NIR spectroscopy is a potential tool to discriminate the soils of both vineyards as well as to quantify differences of soil’s parameters. For that, a total of eight sampling spots were selected at each vineyard taking into consideration the soil type and sampled at different depths. The data analysis was performed using analysis of variance (ANOVA), principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) and partial least squares (PLS) regression. The ANOVA results revealed that 12 out of the 18 parameters analysed through the reference procedures can be considered statistically different (p < 0.05). Regarding PCA, the obtained results revealed a clear separation between the scores of both vineyards either considering NIR spectra or the chemical parameters. The PLS-DA model was able to obtain 100 % of correct predictions for the discrimination of both vineyards. PLS regression analysis using NIR spectra revealed R2 P and RER values higher than 0.85 and 10, respectively, for 8 (pH (H2O), N, Ca2+, Mg2+, SB, CEC, ECEC and GSB) of the 18 chemical parameters evaluated. Concluding, these results demonstrate that it is possible to discriminate the soils of the different vineyards through NIR spectroscopy as well as to quantify several chemical parameters through soils NIR spectra in a rapid, accurate, cost-effective, simple and environmentally friendly way when compared to the reference procedures.
- Automatic and renewable micro-solid-phase extraction based on bead injection lab-on-valve system for determination of tranexamic acid in urine by UHPLC coupled with tandem mass spectrometryPublication . Fernandes, Sara; Barreiros, Luísa; Sá, Paula; Miró, Manuel; Segundo, Marcela A.An automatic micro-solid-phase extraction (μSPE) method using on-line renewable sorbent beads followed by liquid chromatography–tandem mass spectrometry (LC–MS/MS) was established for the determination of tranexamic acid (TXA) in urine. The μSPE method was based on the bead injection (BI) concept combined with the mesofluidic lab-on-valve (LOV) platform. All steps of the μSPE–BI–LOV were implemented by computer programming, rendering enhanced precision on time and flow events. Several parameters, including the type of sorbent, volume and composition of the conditioning solution, washing solution, and eluent composition, were evaluated to improve the extraction efficiency. The best results were obtained with a hydrophilic–lipophilic balanced mixed-mode sorbent, decorated with sulfonic acid groups (Oasis MCX), and 99% acetonitrile–water (50:50, v/v)–1% ammonium hydroxide as eluent. Chromatographic separation was performed using a BEH amide column coupled to MS/MS detection in positive ionization mode. Good linearity was achieved (R2 > 0.998) for TXA concentrations in urine ranging from 300 to 3000 ng mL−1, with LOD and LOQ of 30 and 65 ng mL−1, respectively. Dilution integrity was observed for dilution factors up to 20,000 times, providing the extension of the upper limit of quantification to 12 mg mL−1. The method was validated according to international guidelines and successfully applied to urine samples collected during scoliosis surgery of pediatric patients treated with TXA.
- Benefits of fermented papaya in human healthPublication . Leitão, Mariana; Ribeiro, Tatiana; García, Pablo A.; Barreiros, Luísa; Correia, Patrícia Carla dos SantosFermented foods have been used for several years all over the world, due to their unique nutritional characteristics and because fermentation promotes conservation and food security. More over, fermented foods and beverages have a strong impact on human gut microbiota. Papaya is the fruit of the Carica papaya plant, traditionally used as a medicinal fruit, but there are also references to the use of the fermented form of this fruit. The main purpose of this review is to provide an improved understanding of fermented papaya nutritional and health applications. A literature search was conducted in the PubMed and Google Scholar databases. Both in vitro and in vivo studies were included. According to the retrieved studies, fermented papaya has proven to be an excellent antioxidant and an excellent nutraceutical adjuvant in combined therapies against several diseases, such as Alzheimer’s disease, allergic reactions, anticancer activity, and anemias. Therefore, it is concluded that fermented papaya has many benefits for human health and can be used as prevention or aid in the treatment of various diseases.
- Evaluation of enzymatic digestion conditions for determination of immunoglobulins by tandem mass spectrometryPublication . Guerra, Gabriela S.; Ramos, Inês I.; Barreiros, Luísa; Silva, Eduarda M. P.; Segundo, Marcela A.Immunoassays, namely ELISA, have been the standard method for detecting clinically significant immunoglobulins (Igs). They are based on Ig-antigen interaction, often suffering interference from matrix components. New analytical approaches using detection by tandem mass spectrometry (MS/MS) search for fundamental structure information of target Igs based on protein features. In fact, there are few examples of quantitative assays achieved by liquid chromatography coupled with triple quadrupole (QqQ) mass analyzers. Due to the limited mass range of QqQ, the use of this mass analyzer requires previous tryptic digestion of IgG for analysis of highly specific surrogate peptides. In this work, initial studies on a LC-MS/MS method for the quantitative analysis of IgG are reported. The method relies upon the detection of the generic peptide DTLMISR (Fig. 1), originated from the fraction crystallizable (Fc) region of IgG after enzymatic cleavage. The multiple reaction monitoring transitions used for quantification and identification purposes were, respectively, m/z 418.20 506.10 and 418.20 619.30, corresponding to the fragmentation of double-charged molecular ions. In order to investigate the influence of trypsin concentration on digestion kinetics and efficiency, the trypsin-to-protein ratios 1:20, 1:50 and 1:100 were evaluated. Moreover, the performance of the digestion process was monitored for IgG standards and plasma samples over 18 h at 37 °C. Using a 1:50 ratio, two distinct kinetic profiles were observed for standards and plasma samples with a maximum signal intensity after 6 and 18 h, respectively.
- Fermented Papaya: Available formulations from online marketsPublication . Leitão, Mariana; Ribeiro, Tatiana; García, Pablo; Barreiros, Luísa; Correia, Patrícia; Barreiros, Luisa; Correia, Patrícia Carla dos Santos CorreiaFermentation is a process of central metabolism in which an organism converts a carbohydrate, such as starch or sugar, into an alcohol or an acid. Carica papaya, also known as papaya or pawpaw, belongs to the Caricaceae family and has four genera in the world. Due to papaya’s health benefits, this fruit is considered a valuable nutraceutical with an exceptionally diverse composition, encompassing vitamins and enzymes. Fermented papaya preparations, produced by the fermentation of Carica papaya, are a wellknown food supplement that exhibit anti‑inflammatory, antioxidant, and immunostimulatory action. A descriptive study was carried out to find out which commercial fermented papaya formulations are available in the market. Data were gathered during 2021 from February to March. The main available commercial fermented papaya formulations were searched for on international online shopping sites, such as Amazon®, Naturitas®, Ebay®, Nutribio®, Life Natura®, and Fruugo®. A search was conducted by using the following keywords: “fermented papaya”, “FPP®—Fermented Papaya Preparation” “Fermented papaya extracts”. Fermented papaya is available from several brands and in different dosage forms. Its nutritional composition differs between brands not only in the dose of fermented papaya but also in the presence of other constituents. Many products are available in the online market, making it difficult to choose a suitable supplement because little is known about their labeling and contents to evaluate their appropriateness. Even if the “fermented papaya” composition is included on labels, this does not guarantee that the products have the same fermented papaya composition related to scientific studies with one specific brand (Immun’Âge‑FPP®). Consumers may often interpret anything stated on the label to be authentic merely because it is in print. There are already many commercial fermented papaya formulations available on the market. However, a deep investigation based on its pharmacokinetic properties is mandatory, as is more regulation.
- A importância dos probióticos nas cervejas artesanais: revisão narrativaPublication . Santos, Diana; Pereira, Maria João; Moreira, Fernando; Barreiros, Luísa; Oliveira, Ana Isabel; Pinho, CláudiaA cerveja constitui uma bebida funcional dado o seu valor nutritivo e possível enriquecimento com ingredientes inovadores, que lhe confere propriedades nutricionais benéficas para a saúde do consumidor. Assim, os probióticos são ingredientes ativos passíveis de serem adicionados, pelas inúmeras vantagens na saúde do hospedeiro. Os alimentos funcionais contendo probióticos são geralmente produtos lácteos. Como tal, a funcionalidade probiótica deve ser confirmada noutros veículos. Discutir a viabilidade e os benefícios da incorporação de probióticos em cervejas artesanais. Revisão narrativa com pesquisa de artigos na base de dados PubMed, utilizando os termos de pesquisa “probiotics”, “beer” e “craft beer” combinadas com os operadores booleanos “OR” e “AND”. Incluíram-se artigos com referência a benefícios da incorporação de probióticos nas cervejas artesanais, em língua inglesa e portuguesa, não tendo sido estabelecidos limites temporais. As cervejas artesanais não são filtradas nem pasteurizadas o que lhes confere, genericamente, maior teor de compostos fenólicos totais (TPC) e maior atividade antioxidante. A ausência destas etapas, apesar de fundamentais para a garantia de isenção de contaminações, potencia os benefícios desta cerveja, e a incorporação de probióticos. A incorporação de Saccharomyces cerevisiae var. boulardii em co-fermentação com Saccharomycescerevisiae na cerveja artesanal, revelou-se promissora e viável, tendo-se atingido um elevado número de células viáveis (8,0x106–7,0x107células/mL). Denotou-se ainda o aumento da atividade antioxidante e do teor de polifenóis na cerveja.Por sua vez, durante a co-fermentação com Saccharomycescerevisiae, a bactéria Lactobacillus paracaseiL26 manteve uma elevada viabilidade (>108CFU/mL), evidenciando a boa compatibilidade entre os dois microrganismos. Também a fermentação da cerveja com Lacticaseibacillus para caseiLpc-37 demonstrou um TPC e atividade antioxidante elevados. Aincorporação de probióticos nas cervejas artesanais pode ser uma opção promissora na otimização das propriedades antioxidantes e compostos fenólicos, bem como na contribuição para a manutenção da microbiota intestinal.
- Innovative pedagogical tools for parasitology based on interactive learningPublication . Sequeira, Susie; Sousa, Mariana; Fernandes, Sara; Barreiros, Luísa; Cunha, Agostinho; Cruz, Agostinho; Fernandes, Sara; Barreiros, LuisaParasitic infections in children, in particular ectoparasitoses, remain a public health challenge within the school context in Portugal. As part of the curricular unit “Agentes e Vectores de Doença I” included in the first year of the Bachelor of Pharmacy, pedagogical tools have been developed to raise awareness on this issue among the various stakeholders involved in primary education. The developed activities, in addition to enable the consolidation of technical and scientific knowledge, promote the development of transversal competences, namely soft skills, essential for the training of future health professionals. The created instruments have been successfully applied in teacher training activities and in awareness-raising sessions for children. The adoption of interactive learning approaches has contributed to higher student engagement and better learning outcomes, while simultaneously promoting a culture of education and health promotion supported by innovative and collaborative pedagogical practices.