Browsing by Author "Delerue-Matos, C."
Now showing 1 - 3 of 3
Results Per Page
Sort Options
- Effects of single and combined exposures of gold (nano versus ionic form) and gemfibrozil in a liver organ culture of Sparus aurataPublication . Barreto, A.; Carvalho, A.; Silva, D.; Pinto, E.; Almeida, A.; Paíga, P.; Correia-Sá, L.; Delerue-Matos, C.; Trindade, T.; Soares, A.M.V.M.; Hylland, K.; Loureiro, S.; Oliveira, M.In vitro methods have gained rising importance in ecotoxicology due to ethical concerns. The aim of this study was to assess the single and combined in vitro effects of gold, as nanoparticle (AuNPs) and ionic (Au+) form, and the pharmaceutical gemfibrozil (GEM). Sparus aurata liver organ culture was exposed to gold (4 to 7200 μg·L−1), GEM (1.5 to 15,000 μg·L−1) and combination 80 μg·L−1 gold +150 μg·L−1 GEM for 24 h. Endpoints related with antioxidant status, peroxidative/genetic damage were assessed. AuNPs caused more effects than Au+, increasing catalase and glutathione reductase activities and damaging DNA and cellular membranes.
- Electrochemical genosensor for the detection of Alexandrium minutum dinoflagellatesPublication . Morais, S.L.; Barros, Piedade; Santos, M.; Delerue-Matos, C.; Gomes, A.C.; Fátima Barroso, M.This work addresses the development of a disposable electrochemical genosensor for the detection of the toxic dinoflagellate, Alexandrium minutum. Analyzing public databases, a specific 70 bp DNA probe, targeting A. minutum, was selected and designed. The genosensor methodology implied the immobilization of a A. minutum-specific DNA-capture probe onto screen-printed gold electrodes (SPGE). To improve both the selectivity and to avoid strong secondary structures, that could hinder the hybridization efficiency, a sandwich format of the A. minutum gene was designed using a fluorescein isothiocyanate-labelled signaling DNA probe and enzymatic amplification of the electrochemical signal. Using this electrochemical genosensor, a concentration range from 0.12 to 1.0 nM, a LD of 24.78 pM with a RSD <5.2% was determined. The genosensor was successfully applied to the selective analysis of the targeted A. minutum specific region denatured genomic DNA extracted from toxic dinoflagellates present in the Atlantic Ocean.
- Investigating multiple vegetable oils and recycled variant for microplastics extraction from water, integrated with Raman spectroscopyPublication . Garzón-Vidueira, R.; André, M.; Rede, D.; Barbosa, R.; Rial-Otero, R.; Delerue-Matos, C.; Vilarinho, Rui; Fernandes, Vírginia Cruz; Vilarinho, RuiThe global production and disposal of plastics have led to pervasive contamination of natural environments, representing considerable risks to human health and ecosystems. This study introduces a novel oil-based method for extracting microplastics (MPs) from water samples, with a focus on optimizing extraction conditions and improving the quality of MPs identification using Raman spectroscopy. Various parameters including the type of oil, salinity, temperature, air incorporation, and washing solvent were investigated to enhance extraction efficiency and spectroscopic identification accuracy. Sunflower oil emerged as the preferred extraction medium due to its compatibility with Raman spectroscopy, offering high recovery efficiencies for polypropylene (PP) and polystyrene (PS). Additionally, ethanol was identified as a better washing solvent compared to hexane, improving MPs identification. The optimised method was then applied to environmental water samples, revealing matrix effects and challenges with digestion step. Despite these challenges, the proposed method represents a significant advancement in microplastic analysis, offering reliable detection and quantification in aquatic environments. Further optimisation is needed to address matrix effects and improve recovery efficiency, especially for smaller microplastics.