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1.
Anal Bioanal Chem ; 401(6): 1847-60, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21667062

RESUMO

Chemical analysis of ancient residues of pharmaceutical or cosmetic preparations such as balms or ointments is made problematic by the high complexity of these mixtures, composed of organic and inorganic materials. Consequently, a multi-analytical approach and special caution in the interpretation of the results are necessary. In order to contribute to the improvement of analytical strategies for the characterization of complex residues and to reconstruct ancient medical practices, a replica of a pharmaceutical formulation of the seventeenth century was prepared in the laboratory according to a historically documented recipe. In a round robin exercise, a portion of the preparation was analysed as a blind sample by 11 laboratories using various analytical techniques. These included spectroscopic, chromatographic and mass spectrometric methods. None of the laboratories was able to completely reconstruct the complex formulation, but each of them gave partial positive results. The round robin exercise has demonstrated that the application of a multi-analytical approach can permit a complete and reliable reconstruction of the composition. Finally, on the basis of the results, an analytical protocol for the study of residues of ancient medical and pharmaceutical preparations has been outlined.


Assuntos
Pomadas/química , Tecnologia Farmacêutica/história , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , História do Século XVII , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 229: 117954, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31901803

RESUMO

This paper presents the results of a fully non-invasive photographic and spectroscopic study on a masterpiece by the famous Venetian painter Jacopo Tintoretto (1518-1594): "The Wedding feast at Cana" (1561), located inside the sacristy of the Santa Maria della Salute Basilica in Venice. A restoration campaign was carried out on the painting between 2016 and 2017. Various techniques were chosen to characterize in detail the materials used by the painter, especially pigments: Near Infrared Reflectography (NIR) to identify preparatory sketch and also allowing formulating hypothesis on some pigments; Raman and Fiber Optics Reflectance Spectroscopy (FORS) applied directly to the surface of the object, avoiding sample collection, to identify the pigments palette applied by Tintoretto. Information about binders was also obtained in a totally non-invasive way by using NIR spectroscopy. All analysis points were precisely (±2 mm) registered on a painting virtual map in order to recover them in a future possible conservation project.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 204: 548-567, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-29975917

RESUMO

A selection of historical textile fragments from the Venetian art dealer Moisè Michelangelo Guggenheim collection, ranging from XV to XVIII century, has been investigated by means of non-invasive techniques in order to reveal the coloring materials. Imaging was preliminarily used to visually investigate the selected artwork fragments in order to investigate their structure and conservation conditions; Fiber Optics Reflectance Spectroscopy (FORS) allowed recognizing the main natural dyestuffs, such as indigotin and anthraquinones-based compounds, except the yellow ones, difficultly identifiable when using this non-invasive technique. Collected spectroscopic data have been also elaborated by using a clustering algorithm that permitted to group collected spectra on the basis of similar properties and evidencing their inflection point wavelength as the most influencing feature.

4.
Nanotoxicology ; 9 Suppl 1: 118-32, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25923349

RESUMO

In spite of recent advances in describing the health outcomes of exposure to nanoparticles (NPs), it still remains unclear how exactly NPs interact with their cellular targets. Size, surface, mass, geometry, and composition may all play a beneficial role as well as causing toxicity. Concerns of scientists, politicians and the public about potential health hazards associated with NPs need to be answered. With the variety of exposure routes available, there is potential for NPs to reach every organ in the body but we know little about the impact this might have. The main objective of the FP7 NanoTEST project ( www.nanotest-fp7.eu ) was a better understanding of mechanisms of interactions of NPs employed in nanomedicine with cells, tissues and organs and to address critical issues relating to toxicity testing especially with respect to alternatives to tests on animals. Here we describe an approach towards alternative testing strategies for hazard and risk assessment of nanomaterials, highlighting the adaptation of standard methods demanded by the special physicochemical features of nanomaterials and bioavailability studies. The work has assessed a broad range of toxicity tests, cell models and NP types and concentrations taking into account the inherent impact of NP properties and the effects of changes in experimental conditions using well-characterized NPs. The results of the studies have been used to generate recommendations for a suitable and robust testing strategy which can be applied to new medical NPs as they are developed.


Assuntos
Nanomedicina/métodos , Nanopartículas/toxicidade , Testes de Toxicidade/métodos , Humanos , Técnicas In Vitro/normas , Testes de Toxicidade/normas
5.
J Chromatogr A ; 923(1-2): 97-105, 2001 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-11510565

RESUMO

A very sensitive analytical procedure based on LC-MS for determining trace amounts of the more relevant poly(naphthalenesulfonate) (PNS) contaminants present in environmental waters is presented. Extraction was performed on a styrene-divinylbenzene copolymer resin solid-phase extraction cartridge after addition of ammonium acetate to the sample. Small amounts of ammonium acetate in the mobile phase allowed the determination and characterisation of the four shorter oligomers by liquid chromatography-electrospray mass spectrometry. Under such conditions the electrospray process generates fully ionised molecules which greatly simplifies interpretation of spectra and quantitation. Additionally, confirmatory ions can be generated by the in-source collision-induced decomposition process. The effectiveness of the method was assessed in recovery experiments from drinking and river water samples spiked with commercial mixtures of PNS concrete plasticizers also referred as naphthalenesulfonate-formaldehyde condensates. Moreover, the performance of this method was compared to methods using ion-pair chromatography coupled with fluorimetric and mass spectrometric detection. Method detection limits were in the low picomolar range (1 ng/l for the monomer) for each isomer. In order to evaluate the environmental relevance of PNS type compounds waste, river and ground water grab samples were analysed. Concentrations of PNS oligomers detected in these samples ranged between 53 ng/l and 32 microg/l.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Naftalenossulfonatos/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray/métodos , Poluentes Químicos da Água/isolamento & purificação , Água Doce , Naftalenossulfonatos/química , Sensibilidade e Especificidade , Oligoelementos/isolamento & purificação
6.
Chemosphere ; 44(2): 257-62, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11444308

RESUMO

Aerosolization of natural salt and brackish waters under laboratory conditions is responsible for the transfer of synthetic surfactants such as linear alkylbenzene sulphonate (LAS) from water to the atmosphere. Excluded the lagoon sample which stands apart, on the average ca. 45% of the LAS present at concentrations between 0.1 and 4.1 microg l(-1) in the tested coastal and offshore marine and lagoon waters was transferred to the aerosol extract. The distribution of the individual LAS homologs in the aerosol is very similar to that in water, which indicates no preferential removal from the bulk water of any LAS homolog. The fraction of dissolved organic carbon (DOC) undergoing aerosolization under the same conditions for each tested sample was on an average ca. 3.3%, corresponding to ca. 5.6 mg l(-1). On the average, the enrichment factor of the sea samples, resulting from the changing of the LAS/DOC ratio before and after aerosolization, was ca. 20.


Assuntos
Poluentes Atmosféricos/química , Ácidos Alcanossulfônicos/química , Carbono/química , Tensoativos/química , Poluentes da Água/análise , Aerossóis , Ânions , Solubilidade , Água
7.
Environ Toxicol Chem ; 20(3): 644-51, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11349867

RESUMO

A reliable sperm cell toxicity test procedure has been developed for the Mediterranean sea urchin Paracentrotus lividus. The sensitivity and discriminatory ability of the test were investigated with regard to surfactants and their biotransformation products. Aromatic and aliphatic surfactants of anionic (linear alkylbenzene sulfonates [LAS]) and nonionic (alcohol polyethoxylates [AE] and nonylphenol polyethoxylates [NPE]) types and their aerobic biodegradation products, i.e., sulfophenylcarboxylates (SPC), polyethylene glycols (PEG), carboxylated polyethylene glycols (PEGC), carboxylated AE (AEC), and nonylphenol (NP), were examined in order to elucidate the influence of their molecular structure on toxicity. Experimental results reveal that the sperm cell test showed good discriminatory ability among all tested compounds, median effective concentration (EC50) values differing by about four orders of magnitude. The toxicity of anionic surfactants depends on the length of the alkyl chain and that of nonionic surfactants is due to their length and branching. Much lower toxicity was shown by aerobic biodegradation products in comparison with that of their parent compounds, with the exception of NP. The obtained EC50s were comparable with available literature data and constitute new toxicity data regarding surfactants for sea urchins.


Assuntos
Ouriços-do-Mar/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Tensoativos/toxicidade , Testes de Toxicidade/métodos , Poluentes Químicos da Água/toxicidade , Animais , Ânions/toxicidade , Masculino , Reprodutibilidade dos Testes , Ouriços-do-Mar/metabolismo , Sensibilidade e Especificidade , Espermatozoides/metabolismo , Relação Estrutura-Atividade , Tensoativos/química , Tensoativos/metabolismo , Poluentes Químicos da Água/metabolismo
8.
Aquat Toxicol ; 100(2): 168-77, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20444507

RESUMO

The potential for ecological toxicity associated with nanomaterials is a growing area of investigation, in particular in the aquatic environment. In suspension feeding invertebrates, the cellular immune system and digestive gland are likely to be targeted, due to their highly developed processes for the cellular internalisation of nano- and micro-scale particles that are integral to key physiological functions such as cellular immunity and intracellular digestion. We have recently demonstrated that suspensions of selected commercial nanomaterials, namely Nano carbon black (NCB), C60 fullerene (C60), Nano-titanium dioxide (n-TiO2) and Nanosilica (n-SiO2) induce oxyradical production and lysosomal enzyme release in the hemocytes of the marine mussel Mytilus in vitro. In this work the possible effects of in vivo exposure to these NPs were investigated. Mussels were exposed to different concentrations (0.05-0.2-1-5mg/l) of NP suspensions for 24h and different biomarkers were evaluated in hemocytes, digestive gland and gills. Characterisation of NP suspensions in artificial sea water (ASW) was performed, indicating the formation of agglomerates of different sizes in the nano-micromolar range for different types of NPs. Formation of larger agglomerates was observed at the end of exposure. The results show that all NP suspensions induced significant lysosomal membrane destabilisation in both the hemocytes and the digestive gland, with NCB>>C60>n-TiO2, >n-SiO2. In the digestive gland, all NPs induced lysosomal lipofuscin accumulation only at the highest concentrations tested to a different extent depending on the NP type. NCB, TiO2 and SiO2 also induced lysosomal neutral lipid accumulation. Moreover, all NPs increased the activity of the antioxidant enzyme catalase, with n-SiO2>NCB≅TiO2>C60; NCB and n-TiO2 also stimulated glutathione transferase (GST). Changes in catalase and GST activities were also observed in gills, with both increases and decreases depending on NP type and concentration. The reported results demonstrate that in mussels responses to exposure to NP suspensions involve changes in lysosomal and oxidative stress biomarkers in the digestive gland, suggesting uptake of NP aggregates/agglomerates mainly through the digestive system. Overall, these data further support the hypothesis that suspension feeding invertebrates represent a significant target for NPs in the aquatic environment.


Assuntos
Biomarcadores/metabolismo , Mytilus/efeitos dos fármacos , Nanopartículas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Catalase/metabolismo , Fulerenos/toxicidade , Glutationa Transferase/metabolismo , Mytilus/enzimologia , Mytilus/metabolismo , Dióxido de Silício/toxicidade , Fuligem/toxicidade , Titânio/toxicidade
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