Read all posts from October 2014

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Thermo-responsive molecularly imprinted monolith in extraction

Molecularly imprinted polymers (MIPs) are widely employed sorbents due to their improved selectivity. They are synthesized in the presence of the analyte, which is called template, and therefore the polymeric network is constructed around the target leaving selective chemical cavities when it is washed away. After the bulk synthesis, the polymer is crashed and sieved to obtain a solid with a particle size as homogeneous as possible. In a recent article published in Analytical and Bioanalytical Chemistry, researchers from the Tianjin Medical University at China have proposed a smart MIP monolith for the extraction of ketoprofen from milk samples.Link to the post

Simultaneous electromembrane extraction of acidic and basic drugs

In most of the cases, microextraction techniques are applied to isolate and preconcentrate a target compound or a narrow group of them. The simultaneous extraction of a given sample into fractions of analytes with similar chemical characteristics is especially interesting in bioanalysis since biological samples contain plenty of compounds with biological effects that cover a wide range of polarities. Link to the post

Solid phase microextraction of volatile organic compounds from cigarette smoke

The determination of volatile compounds in gas samples is a challenging issue. Firstly, because it is difficult to collect large and representative samples and secondly due to the potential losses of the analyte by diffusion through the pores of the sample container. Moreover, the mandatory preconcentration step that must be implemented prior to the instrumental analysis must be carried out maintaining the sample homogeneity. Link to the post

Highlighted articles (October 16, 2014)

We recommend the following articles that deal with different aspects related with sample preparation. Link to the post

Octadecyl pipette tip coupled to electrospray ionization mass spectrometry

The availability of easy to handle interfaces for the direct analysis of samples by mass spectrometry is highly desirable as it clearly simplifies the analytical measurement process. Moreover, the reduction of errors in the final result given can be highlighted as a great advantage. These interfaces must reduce the amount of interferents that can eventually reach the detector while providing a reproducible and quantitative response. Link to the post

Highlighted articles (October 22, 2014)

We recommend the following articles that deal with different aspects related to sample preparation. Link to the post

Gas assisted micro liquid-liquid extraction: a simple and efficient technique for high throughput bioanalysis

The article that we highlight today describes a new, simple, efficient and automated extraction technique for high throughput bioanalysis. It has been published in Analytical Chemistry under the title "Gas Pressure Assisted Microliquid–Liquid Extraction Coupled Online to Direct Infusion Mass Spectrometry: A New Automated Screening Platform for Bioanalysis" (1). It is interesting to note that we have described another article from the same research group in a previous post. Link to the post

Highlighted articles (October 29, 2014)


We recommend the following articles that deal with different aspects related to sample preparation. Link to 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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