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Speciation analysis of antimony in marine biota is not well documented, and no specific extraction procedure of antimony species from algae and mollusk samples can be found in the literature. This work presents a suitable methodology for the speciation of antimony in marine biota (algae and mollusk samples). The extraction efficiency of total antimony and the stability of Sb(III), Sb(V) and trimethylantimony(V) in different extraction media (water at 25 and 90 degrees C, methanol, EDTA and citric acid) were evaluated by analyzing the algae Macrosystis integrifolia (0.55+/-0.04mugSbg(-1)) and the mollusk Mytilus edulis (0.23+/-0.01mugSbg(-1)). The speciation analysis was performed by anion exchange liquid chromatography (post-column photo-oxidation) and hydride generation atomic fluorescence spectrometry as detection system (HPLC-(UV)-HG-AFS). Results demonstrated that, based on the extraction yield and the stability, EDTA proved to be the best extracting solution for the speciation analysis of antimony in these matrices. The selected procedure was applied to antimony speciation in different algae samples collected from the Chilean coast. Only the inorganic Sb(V) and Sb(III) species were detected in the extracts. In all analyzed algae the sum of total antimony extracted (determined in the extracts after digestion) and the antimony present in the residue was in good agreement with the total antimony concentration determined by HG-AFS. However, in some extracts the sum of antimony species detected was lower than the total extracted, revealing the presence of unknown antimony species, possibly retained on the column or not detected by HPLC-(UV)-HG-AFS. Further work must be carried out to elucidate the identity of these unknown species of antimony.
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http://dx.doi.org/10.1016/j.talanta.2007.04.015 | DOI Listing |
Evolution
September 2025
Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada M5S 3B2.
Intraspecific phenotypic variation provides the basic substrate upon which the evolutionary processes that give rise to morphological innovation, such as adaptation, operate. Work in living clades has shown standing population-level variation fuels ecological speciation and gives rise to adaptive radiations. Despite its importance in evolutionary biology, the role of intraspecific variation in shaping phylogenetic and macroevolutionary patterns and processes has remained underexplored.
View Article and Find Full Text PDFSyst Biol
September 2025
Department of Biology, University of North Carolina at Chapel Hill, USA.
For many questions in ecology and evolution, the most relevant data to consider are attributes of lineage pairs. Comparative tests for causal relationships among traits like 'diet niche overlap', 'divergence time', and 'strength of reproductive isolation (RI)' - measured for pairwise combinations of related species or populations - have led to several groundbreaking insights, but the correct statistical approach for these analyses has never been clear. Lineage-pair traits are non-independent, but unlike the expected covariance among species' traits, which is captured by a phylogenetic covariance matrix arising from a given model, the expected covariance among lineage-pair traits has not been explicitly formulated.
View Article and Find Full Text PDFAnal Bioanal Chem
September 2025
Department of Chemistry, School of Chemistry, Food and Pharmacy, University of Reading, Reading, RG6 6DX, UK.
Fungal pathogens pose a growing threat to global health, necessitating rapid and accurate identification methods. Here, liquid atmospheric pressure matrix-assisted laser desorption/ionisation (LAP-MALDI) mass spectrometry (MS) is applied to fast lipid and protein profiling of Candida albicans and Saccharomyces cerevisiae from cultured colonies. Species-specific lipid profiles were observed in the m/z 600-1100 range, dominated by phospholipids as confirmed by tandem mass spectrometry (MS/MS).
View Article and Find Full Text PDFJ Phys Chem B
September 2025
Université de Lorraine, CNRS, GeoRessources, Nancy F-54000, France.
Quartz is among the most abundant minerals on Earth, but its surface chemistry under varying pH conditions remains not fully understood. In particular, the interplay between pH, amphoteric behavior, and water adsorption properties has been the subject of a long-standing debate. This study presents a comprehensive, multitechnique investigation into the pH-dependent interfacial chemistry of quartz.
View Article and Find Full Text PDFAnal Methods
September 2025
Giresun University, Faculty of Arts and Sciences, Department of Chemistry, 28200 Giresun, Turkey.
Metal pollution, particularly chromium, in water and food samples is a critical issue due to its transfer to the human body through the food chain and its threat to human health. Among the chromium species that can be found in water samples, chromates are classified as toxic by scientific authorities. Spectroscopic instruments have limitations in metal speciation analysis, and there is a need for suitable methods that allow chromium speciation.
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