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Accelerated solvent extraction for the evaluation ofprenatal exposure to drugs of abuse Drug abuse is an important and worldwide problem with several health and legal connotations. The intake of these substances during pregnancy is especially critical since it affects both the mother and the growing infant. In this sense, potential effects caused by drug intake include decreased birth weight, body length and head circumference, intra-uterine growth retardation, impairment of normal fetal brain development, placental insufficiency, fetal distress, intra-uterine death, and a higher risk of premature birth. (Read more) Monitoring a single C18 particle by confocal Raman microscopy Solid phase extraction (SPE) is a consolidated sample treatment technique based on the retention of the target analytes in an appropriate sorbent thanks to different chemical interactions. SPE allows the enhancement of the selectivity and sensitivity of an analytical methodology through removing pote

Mass spectrometric analysis of surfaces by electro-focusing liquid extractive surface analysis

Surface analysis by mass spectrometry is an interesting research topic with plenty of applications. This type of analysis requires a previous sampling of the planar material and the introduction of the surface components on the mass spectrometer. As the readers know, there are different alternatives in this context, matrix-assisted laser desorption ionization (MALDI) being one of the most known. However, the mass spectrometric analysis of a surface can be also performed by direct contact liquid interfaces. These approaches consist of a special interface that allows the direct contact of a liquid phase (of defined chemical characteristics) in the form of a drop with the surface. This drop is capable to extract some of the compounds deposited on the surface. After a defined sampling (or extraction) time, the drop is retracted and sent to the MS for further analysis. Chromatographic techniques can be used when selectivity issues appears due to the sample complexity. The spatial resol

MIP integration into a fiber-optic evanescent sensor

Analytical and Bioanalytical Chemistry journal has published a novel miniaturized extraction method for the determination of bisphenol A in plastic products treated at different temperatures. The main advantage of the proposed approach is that it is a fiber-optic evanescent wave sensor. In this case, a molecularly imprinted polymer is synthesized on a fiber column to which an optical fiber is adapted. As far as the detection limit is concerned, the sensor uses a low volume cell (20 µL) formed by the fiber and the capillary. The main innovation of this sensing device is that the fiber optical column and capillary are set in parallel to the PMT detector instead of the conventional vertical arrangement. In this way, the sensor sensitivity is increased by decreasing the background and enhancing the fluorescence response. The authors explain in their article the fabrication of the BPA-MIP as well as the sequential operation of the proposed system. In addition to the detailed optimizat

Monitoring a single C18 particle by confocal Raman microscopy

Solid phase extraction (SPE) is a consolidated sample treatment technique based on the retention of the target analytes in an appropriate sorbent thanks to different chemical interactions. SPE allows the enhancement of the selectivity and sensitivity of an analytical methodology through removing potential interferences and increasing the concentration of the target compounds. The latter depends directly on the extraction efficiency (defined as the absolute extraction recovery), as well as the volumes of the sample processed and the final eluent. Objectively seen, the final elution produces a dilution of the analyte which is previously confined in a lower amount/volume of the sorptive phase, thus reducing the potential enrichment factors of the technique. Solid phase microextraction (SPME) faces up the "elution problem" with a clever strategy that consists on the elution of the analytes inside of the instrument. In this sense, the fiber with the extracted analytes is intr

Accelerated solvent extraction for the evaluation of prenatal exposure to drugs of abuse

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Drug abuse is an important and worldwide problem with several health and legal connotations. The intake of these substances during pregnancy is especially critical since it affects both the mother and the growing infant. In this sense, potential effects caused by drug intake include decreased birth weight, body length and head circumference, intra-uterine growth retardation, impairment of normal fetal brain development, placental insufficiency, fetal distress, intra-uterine death, and a higher risk of premature birth. Despite the importance of this problem, epidemiological studies are scarce due to different reasons. The absence of self-reports owing to the potential negative legal consequences and the social stigma that is attached to admitting drug abuse, are the main causes. In this context, it would be interesting to develop analytical methodologies capable to detect and quantify this in-utero exposure to drugs in order to prevent negative consequences or to enable the obtaini