0000000000004749

AUTHOR

Rafael Lucena

Carbon fibers as green and sustainable sorbent for the extraction of isoflavones from environmental waters.

Abstract Isoflavones are a group of phytoestrogens of important environmental concern due to their endocrine disrupting effects. This article presents a rapid, green, and sustainable method for determining four isoflavones (daidzein, genistein, formononetin, and biochanin A) in environmental waters complying with current trends in Analytical Chemistry. The method consists of in-syringe dispersive solid-phase extraction (DSPE) as the extraction approach, using carbon fibers as extraction material. The synthesis of carbon fibers is simple and sustainable, since it only requires a natural product such as raw cotton as precursor, which is thermally treated (600 °C for 30 min) in an inert (Ar) a…

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Synergistic combination of polyamide-coated paper-based sorptive phase for the extraction of antibiotics in saliva.

Abstract The development of analytical methods that allow the simultaneous determination of a wide range of analytes with different properties is one of the focuses of attention in Analytical Chemistry. This work describes a proof-of-concept of the synergistic extraction of a planar paper-based sorptive phase modified with a polyamide such as nylon. This as-prepared sorptive phase enables the extraction of six penicillin-derived antibiotics of different polarity from human saliva samples in the same analysis, since the analytes either interact with the paper or with the nylon. The synthesis of the sorptive phase is simple as it only requires dipping the paper into an organic solution of the…

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Sensitive determination of polycyclic aromatic hydrocarbons in water samples using monolithic capillary solid-phase extraction and on-line thermal desorption prior to gas chromatography-mass spectrometry.

A methacrylate-based monolithic capillary column has been evaluated for the preconcentration of polycyclic aromatic hydrocarbons (PAHs) from environmental water samples. For this purpose, the monolyte was in situ synthesized in a 6cm×0.32mm id fused-silica capillary. The microextraction unit was fitted to a micro-HPLC pump to pass 10mL of sample. The isolated pollutants were eluted by means of 10μL of methanol, the organic phase being directly collected in a specific interface that can be fitted to the injection port of the gas chromatograph without modification. The interface allows the on-line thermal desorption of the PAHs, avoiding the dilution and providing enough sensitivity to reach …

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Dispersive micro-solid phase extraction

Abstract Dispersive micro-solid phase extraction (D-μSPE) has gained special attention in the sample preparation process due to its simplicity, speed and efficiency. Different dispersion approaches have been used within this technique to allow a close contact between the sorbent and the donor sample solution during the entrapping step, but also between the sorbent and the solvent in the elution step. This dispersion favors the kinetics of both sorption and elution and therefore increases the efficiency of the overall extraction procedure. This technique boasts of high versatility owing to the great variety of solids available, covering a high range of chemical functionalities. This article …

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