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Optical monitoring of single drop microextraction

Single drop microextraction, the first liquid phase microextraction technique, is a simple approach consisting of the extraction of the target analytes from the sample into a small drop of extractant. The characteristics of the drop, specially its chemical nature and mechanical stability, are key to guarantee the success of the extraction. The chemical composition defines the affinity towards the target analytes which are, in fact, extracted depending on their solubility. The mechanical stability of the drop during the extraction is critical since the drop detachment would ruin the extraction.(Read the post)

Moving miniaturization a step forward

Microextraction techniques have evolved from classical extraction procedures following three main trends, namely: miniaturization, simplification and automation, which have not received a similar attention in the last decades. In fact, simplification and miniaturization (in different degrees) are almost inherent to the majority of the new approaches while automation is, in some cases, considered in a lesser extent. However, all these facets are capital, especially if we consider the new demands of analytical information. The modern analytical platforms will have to process a larger number of samples providing information even faster and cheaper. It seems obvious that in this scenario, the previous trends should go a step further.(Read the post)

Trapping analytes with carbon nanotubes sponges

Carbon nanotubes sponges are three dimensional structures formed by the random self-assembly of these nanostructures during their synthesis. They are produced by the classical chemical vapor deposition method simply using special catalysts like ferrocene. The structure of an sponge can be observed in Figure 1A which shows a scanning electron micrograph of the bulk material.(Read the post)

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Gold coated magnetic beads for electrochemical detection

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Rotating Disk Sorptive Extraction

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