Distribution, occurrence and biotoxin composition of the main shellfish toxin producing microalgae within European waters: A comparison of methods of analysis.

Harmful algal blooms (HABs) are a natural global phenomena emerging in severity and extent. Incidents have many economic, ecological and human health impacts. Monitoring and providing early warning of toxic HABs are critical for protecting public health. Current monitoring programmes include measuring the number of toxic phytoplankton cells in the water and biotoxin levels in shellfish tissue. As these efforts are demanding and labour intensive, methods which improve the efficiency are essential. This study compares the utilisation of a multitoxin surface plasmon resonance (multitoxin SPR) biosensor with enzyme-linked immunosorbent assay (ELISA) and analytical methods such as high performance liquid chromatography with fluorescence detection (HPLC-FLD) and liquid chromatography–tandem mass spectrometry (LC–MS/MS) for toxic HAB monitoring efforts in Europe. Seawater samples (n = 256) from European waters, collected 2009–2011, were analysed for biotoxins: saxitoxin and analogues, okadaic acid and dinophysistoxins 1/2 (DTX1/DTX2) and domoic acid responsible for paralytic shellfish poisoning (PSP), diarrheic shellfish poisoning (DSP) and amnesic shellfish poisoning (ASP), respectively. Biotoxins were detected mainly in samples from Spain and Ireland. France and Norway appeared to have the lowest number of toxic samples. Both the multitoxin SPR biosensor and the RNA microarray were more sensitive at detecting toxic HABs than standard light microscopy phytoplankton monitoring. Correlations between each of the detection methods were performed with the overall agreement, based on statistical 2 × 2 comparison tables, between each testing platform ranging between 32% and 74% for all three toxin families illustrating that one individual testing method may not be an ideal solution. An efficient early warning monitoring system for the detection of toxic HABs could therefore be achieved by combining both the multitoxin SPR biosensor and RNA microarray.

Point-and-shoot: rapid quantitative detection methods for on-site food fraud analysis – moving out of the laboratory and into the food supply chain

Major food adulteration and contamination events occur with alarming regularity and are known to be episodic, with the question being not if but when another large-scale food safety/integrity incident will occur. Indeed, the challenges of maintaining food security are now internationally recognised. The ever increasing scale and complexity of food supply networks can lead to them becoming significantly more vulnerable to fraud and contamination, and potentially dysfunctional. This can make the task of deciding which analytical methods are more suitable to collect and analyse (bio)chemical data within complex food supply chains, at targeted points of vulnerability, that much more challenging. It is evident that those working within and associated with the food industry are seeking rapid, user-friendly methods to detect food fraud and contamination, and rapid/high-throughput screening methods for the analysis of food in general. In addition to being robust and reproducible, these methods should be portable and ideally handheld and/or remote sensor devices, that can be taken to or be positioned on/at-line at points of vulnerability along complex food supply networks and require a minimum amount of background training to acquire information rich data rapidly (ergo point-and-shoot). Here we briefly discuss a range of spectrometry and spectroscopy based approaches, many of which are commercially available, as well as other methods currently under development. We discuss a future perspective of how this range of detection methods in the growing sensor portfolio, along with developments in computational and information sciences such as predictive computing and the Internet of Things, will together form systems- and technology-based approaches that significantly reduce the areas of vulnerability to food crime within food supply chains. As food fraud is a problem of systems and therefore requires systems level solutions and thinking.

Evaluation of the Evidential Value of the Elemental Composition of Glass, Ink and Paper by Laser-Based Micro-Spectrochemical Methods

Elemental analysis can become an important piece of evidence to assist the solution of a case. The work presented in this dissertation aims to evaluate the evidential value of the elemental composition of three particular matrices: ink, paper and glass. In the first part of this study, the analytical performance of LIBS and LA-ICP-MS methods was evaluated for paper, writing inks and printing inks. A total of 350 ink specimens were examined including black and blue gel inks, ballpoint inks, inkjets and toners originating from several manufacturing sources and/or batches. The paper collection set consisted of over 200 paper specimens originating from 20 different paper sources produced by 10 different plants. Micro-homogeneity studies show smaller variation of elemental compositions within a single source (i.e., sheet, pen or cartridge) than the observed variation between different sources (i.e., brands, types, batches). Significant and detectable differences in the elemental profile of the inks and paper were observed between samples originating from different sources (discrimination of 87 – 100% of samples, depending on the sample set under investigation and the method applied). These results support the use of elemental analysis, using LA-ICP-MS and LIBS, for the examination of documents and provide additional discrimination to the currently used techniques in document examination. In the second part of this study, a direct comparison between four analytical methods (µ-XRF, solution-ICP-MS, LA-ICP-MS and LIBS) was conducted for glass analyses using interlaboratory studies. The data provided by 21 participants were used to assess the performance of the analytical methods in associating glass samples from the same source and differentiating different sources, as well as the use of different match criteria (confidence interval (±6s, ±5s, ±4s, ±3s, ±2s), modified confidence interval, t-test (sequential univariate, p=0.05 and p=0.01), t-test with Bonferroni correction (for multivariate comparisons), range overlap, and Hotelling’s T2 tests. Error rates (Type 1 and Type 2) are reported for the use of each of these match criteria and depend on the heterogeneity of the glass sources, the repeatability between analytical measurements, and the number of elements that were measured. The study provided recommendations for analytical performance-based parameters for µ-XRF and LA-ICP-MS as well as the best performing match criteria for both analytical techniques, which can be applied now by forensic glass examiners.

Drug of abuse analysis: new methods in herbal and biological matrices for medicinal chemistry and forensic investigation

In this Ph.D. project, original and innovative approaches for the quali-quantitative analysis of abuse substances, as well as therapeutic agents with abuse potential and related compounds were designed, developed and validated for application to different fields such as forensics, clinical and pharmaceutical. All the parameters involved in the developed analytical workflows were properly and accurately optimised, from sample collection to sample pretreatment up to the instrumental analysis. Advanced dried blood microsampling technologies have been developed, able of bringing several advantages to the method as a whole, such as significant reduction of solvent use, feasible storage and transportation conditions and enhancement of analyte stability. At the same time, the use of capillary blood allows to increase subject compliance and overall method applicability by exploiting such innovative technologies. Both biological and non-biological samples involved in this project were subjected to optimised pretreatment techniques developed ad-hoc for each target analyte, making also use of advanced microextraction techniques. Finally, original and advanced instrumental analytical methods have been developed based on high and ultra-high performance liquid chromatography (HPLC,UHPLC) coupled to different detection means (mainly mass spectrometry, but also electrochemical, and spectrophotometric detection for screening purpose), and on attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) for solid-state analysis. Each method has been designed to obtain highly selective, sensitive yet sustainable systems and has been validated according to international guidelines. All the methods developed herein proved to be suitable for the analysis of the compounds under investigation and may be useful tools in medicinal chemistry, pharmaceutical analysis, within clinical studies and forensic investigations.

Identification of sunflower genotypes suitable for organic agriculture and development of analytical tools for their traceability

Thanks to the development and combination of molecular markers for the genetic traceability of sunflower varieties and a gas chromatographic method for the determination of the FAs composition of sunflower oil, it was possible to implement an experimental method for the verification of both the traceability and the variety of organic sunflower marketed by Agricola Grains S.p.A. The experimental activity focused on two objectives: the implementation of molecular markers for the routine control of raw material deliveries for oil extraction and the improvement and validation of a gas chromatographic method for the determination of the FAs composition of sunflower oil. With regard to variety verification and traceability, the marker systems evaluated were the following: SSR markers (12) arranged in two multiplex sets and SCAR markers for the verification of cytoplasmic male sterility (Pet1) and fertility. In addition, two objectives were pursued in order to enable a routine application in the industrial field: the development of a suitable protocol for DNA extraction from single seeds and the implementation of a semi-automatic capillary electrophoresis system for the analysis of marker fragments. The development and validation of a new GC/FID analytical method for the determination of fatty acids (FAME) in sunflower achenes to improve the quality and efficiency of the analytical flow in the control of raw and refined materials entering the Agricola Grains S.p.A. production chain. The analytical performances being validated by the newly implemented method are: linearity of response, limit of quantification, specificity, precision, intra-laboratory precision, robustness, BIAS. These parameters are used to compare the newly developed method with the one considered as reference - Commission Regulation No. 2568/91 and Commission Implementing Regulation No. 2015/1833. Using the combination of the analytical methods mentioned above, the documentary traceability of the product can be confirmed experimentally, providing relevant information for subsequent marketing.

Phytochemical Markers Of Different Types Of Red Propolis.

Propolis is a resin that bees collect from different plant sources and use in the defense of the bee community. The intricate composition of propolis varies depending on plant sources from different geographic regions and many types have been reported. Red coloured propolis found in several states in Brazil and in other countries has known antimicrobial and antioxidant activity. Different analytical methods have been applied to studies regarding the chemical composition and plant origins of red propolis. In this study samples of red propolis from different regions have been characterised using direct infusion electrospray ionisation mass spectrometry (ESI(-)-MS) fingerprinting. Data from the fingerprints was extracted and analysed by multivariate analysis to group the samples according to their composition and marker compounds. Despite similar colour, the red coloured propolis samples were divided into three groups due to contrasting chemical composition, confirming the need to properly characterise the chemical composition of propolis.

Determination Of Flavanones In Orange Juices Obtained From Different Sources By Hplc/dad.

Flavanones (hesperidin, naringenin, naringin, and poncirin) in industrial, hand-squeezed orange juices and from fresh-in-squeeze machines orange juices were determined by HPLC/DAD analysis using a previously described liquid-liquid extraction method. Method validation including the accuracy was performed by using recovery tests. Samples (36) collected from different Brazilian locations and brands were analyzed. Concentrations were determined using an external standard curve. The limits of detection (LOD) and the limits of quantification (LOQ) calculated were 0.0037, 1.87, 0.0147, and 0.0066 mg 100 g(-1) and 0.0089, 7.84, 0.0302, and 0.0200 mg 100 g(-1) for naringin, hesperidin, poncirin, and naringenin, respectively. The results demonstrated that hesperidin was present at the highest concentration levels, especially in the industrial orange juices. Its average content and concentration range were 69.85 and 18.80-139.00 mg 100 g(-1). The other flavanones showed the lowest concentration levels. The average contents and concentration ranges found were 0.019, 0.01-0.30, and 0.12 and 0.1-0.17, 0.13, and 0.01-0.36 mg 100 g(-1), respectively. The results were also evaluated using the principal component analysis (PCA) multivariate analysis technique which showed that poncirin, naringenin, and naringin were the principal elements that contributed to the variability in the sample concentrations.

In Vitro Evaluation Of Sun Protection Factor And Stability Of Commercial Sunscreens Using Mass Spectrometry.

Sunlight exposure causes several types of injury to humans, especially on the skin; among the most common harmful effects due to ultraviolet (UV) exposure are erythema, pigmentation and lesions in DNA, which may lead to cancer. These long-term effects are minimized with the use of sunscreens, a class of cosmetic products that contains UV filters as the main component in the formulation; such molecules can absorb, reflect or diffuse UV rays, and can be used alone or as a combination to broaden the protection on different wavelengths. Currently, worldwide regulatory agencies define which ingredients and what quantities must be used in each country, and enforce companies to conduct tests that confirm the Sun Protection Factor (SPF) and the UVA (Ultraviolet A) factor. Standard SPF determination tests are currently conducted in vivo, using human subjects. In an industrial mindset, apart from economic and ethical reasons, the introduction of an in vitro method emerges as an interesting alternative by reducing risks associated to UV exposure on tests, as well as providing assertive analytical results. The present work aims to describe a novel methodology for SPF determination directly from sunscreen formulations using the previously described cosmetomics platform and mass spectrometry as the analytical methods of choice.

Espécies reativas de oxigênio e de nitrogênio, antioxidantes e marcadores de dano oxidativo em sangue humano: principais métodos analíticos para sua determinação

We review here the chemistry of reactive oxygen and nitrogen species, their biological sources and targets; particularly, biomolecules implicated in the redox balance of the human blood, and appraise the analytical methods available for their detection and quantification. Those biomolecules are represented by the enzymatic antioxidant defense machinery, whereas coadjutant reducing protection is provided by several low molecular weight molecules. Biomolecules can be injured by RONS yielding a large repertoire of oxidized products, some of which can be taken as biomarkers of oxidative damage. Their reliable determination is of utmost interest for their potentiality in diagnosis, prevention and treatment of maladies.

Contaminação de produtos de higiene e cosméticos por n-nitrosaminas

N-nitrosamines are carcinogenic compounds that have been found during the last three decades in a variety of consumer products, including cosmetic and personal care products, and their raw materials. These compounds are formed from amine precursors and nitrosating agents present in the formulations. This paper reviews the formation and occurrence of N-nitrosamines in cosmetic products, as well as presents considerations about analytical, toxicological and regulatory aspects.

Química forense: perspectivas sobre novos métodos analíticos aplicados à documentoscopia, balística e drogas de abuso

In this review recent methods developed and applied to solve criminal occurences related to documentoscopy, ballistic and drugs of abuse are discussed. In documentoscopy, aging of ink writings, the sequence of line crossings and counterfeiting of documents are aspects to be solved with reproducible, fast and non-destructive methods. In ballistic, the industries are currently producing ''lead-free'' or ''nontoxic'' handgun ammunitions, so new methods of gunshot residues characterization are being presented. For drugs analysis, easy ambient sonic-spray ionization mass spectrometry (EASI-MS) is shown to provide a relatively simple and selective screening tool to distinguish m-CPP and amphetamines (MDMA) tablets, cocaine and LSD.

O processo de ensino-treinamento da tecnica e tatica no basquetebol do Brasil : um estudo sobe a otica de professores do ensino superior e tecnicos de elite

Universidade Estadual de Campinas . Faculdade de Educação Física

Contaminantes voláteis provenientes de embalagens plásticas: desenvolvimento e validação de métodos analíticos

Plastic packaging materials intended for use in food packaging is an area of great interest from the scientific and economic point of view due to the irreversible internationalization and globalization process of food products. Nevertheless, a debate related to food safety aspects has emerged within the scientific community. Therefore, the development of analytical methods that allow identifying and quantifying chemical substances of toxicological potential in the packaging is considered essential. This article focuses on the main analytical methods, including validation parameters, as well as extraction and quantification techniques for determination of volatile organic compounds from food packaging materials.

Fidedignidade de rótulos de alimentos comercializados no município de São Paulo, SP

OBJETIVO: Avaliar a fidedignidade das informações sobre dados nutricionais declarados em rótulos de alimentos comercializados. MÉTODOS: Foram avaliados 153 alimentos industrializados habitualmente consumidos por crianças e adolescentes, comercializados no município de São Paulo (SP) entre os anos de 2001 e 2005. Os teores de nutrientes informados pelos rótulos foram confrontados com os resultados obtidos por métodos analíticos (físico-químicos) oficiais, considerando a variabilidade de 20% tolerada pela legislação vigente, para aprovar ou condenar as amostras. Foram calculadas médias, desvios-padrão e intervalos com 95% de confiança para os nutrientes analisados, assim como a distribuição da freqüência percentual de amostras condenadas. RESULTADOS: Todos os produtos salgados analisados apresentaram inconformidades relativamente ao conteúdo de fibra alimentar, sódio ou de gorduras saturadas. Os produtos doces apresentaram variação de zero a 36% de condenação relativamente ao teor de fibra alimentar. Mais da metade (52%) dos biscoitos recheados foram condenados quanto à quantidade de gorduras saturadas. Os nutrientes implicados com a obesidade e suas complicações para a saúde foram aqueles que apresentaram maiores proporções de inconformidade. A falta de fidedignidade das informações de rótulos nas amostras analisadas viola as disposições da Resolução da Diretoria Colegiada 360/03 da ANVISA e os direitos garantidos pela lei de Segurança Alimentar e Nutricional e pelo Código de Defesa do Consumidor. CONCLUSÕES: Foram encontrados altos índices de não conformidade dos dados nutricionais nos rótulos de alimentos destinados ao público adolescente e infantil, indicando a urgência de ações de fiscalização e de outras medidas de rotulagem nutricional

Enzymatic differences between the endophyte Guignardia mangiferae (Botryosphaeriaceae) and the citrus pathogen G. citricarpa

The endophyte Guignardia mangiferae is closely related to G. citricarpa, the causal agent of citrus black spot; for many years these species had been confused with each other. The development of molecular analytical methods has allowed differentiation of the pathogen G. citricarpa from the endophyte G. mangiferae, but the physiological traits associated with pathogenicity were not described. We examined genetic and enzymatic characteristics of Guignardia spp strains; G. citricarpa produces significantly greater amounts of amylases, endoglucanases and pectinases, compared to G. mangiferae, suggesting that these enzymes could be key in the development of citrus black spot. Principal component analysis revealed pectinase production as the main enzymatic characteristic that distinguishes these Guignardia species. We quantified the activities of pectin lyase, pectin methylesterase and endopolygalacturonase; G. citricarpa and G. mangiferae were found to have significantly different pectin lyase and endopolygalacturonase activities. The pathogen G. citricarpa is more effective in pectin degradation. We concluded that there are significant physiological differences between the species G. citricarpa and G. mangiferae that could be associated with differences in pathogenicity for citrus plants.