Solid phase microextraction in Mars exploration

By R. Lucena -
We recover today an interesting article published a few months ago in the International Journal of Astrobiology. The search for life (or trace remains of it) in Mars is still discussed in the scientific community. In this sense, organic molecules can be considered as tracers of a potential existing life or extinct life. However, the extreme conditions of Mars surface (UV solar radiation, for example) are not the best environment to preserve these organic molecules. Polycyclic aromatic hydrocarbons (PAHs), which are ubiquitous in the solar system, are especially resistant to these hard conditions. In fact, PAHs have been detected in meteorites.

In this article, the authors evaluated the potential of solid phase microextraction (SPME) under its headspace (HS) mode for the extraction of PAHs in Mars analogue soil samples. The final identification and determination of the extracted analytes are achieved by means of gas chromatography-mass spectrometry.

Soil obtained near to Mars Dessert Research Station (MDRS, Utah) as well as from Peru and Denmark, were evaluated as model samples due to their similarity to the red planet surface. HS-SPME results an efficient alternative to the determination of PAHs in soil samples although compounds with more than four rings cannot be efficiently extracted due to their low vapor pressures. In this study, the potential of SPME is also compared to liquid extraction using certified reference materials.


For more detailed information, the readers are referred to the article.

Link to the article: Analysis of Mars analogue soil samples using solid-phase microextraction, organic solvent extraction and gas chromatography/mass spectrometry

Other links:

Link to: Qualitative analysis of soils samples using solid phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS)






Comments

Post a Comment

Popular posts from this blog

Fabric phase sorptive extraction: a new generation green sample preparation strategy

By -
Image
by Dr. Abuzar Kabir, International Forensic Research Institute, Department of Chemistry and Biochemistry, Florida International University, Miami, Florida, USA Fabric phase sorptive extraction (FPSE), the most recent member of the sorptive microextraction family, has innovatively incorporated both solid phase microextraction (SPME) and solid phase extraction (SPE) techniques into a single technology platform. FPSE utilizes permeable natural/synthetic fabrics e.g., cotton, polyester, fiber glass supports to chemically bind sol-gel hybrid inorganic-inorganic sorbents. A 5 cm2unit of coated fabric (2.5 cm x 2.0 cm) is typically used as the extraction media which can be inserted directly into the sample container. Extraction of the analytes is generally expedited by using a magnetic stir bar to diffuse the analyts into the sample matrix so that rapid mass transfer from the sample matrix to the extraction medium takes place.Once the mass transfer equilibrium between the FPSE media and
Read more

Gold coated magnetic beads for electrochemical detection

By -
Image
This post summarizes an interesting article, recently accepted for publication in Analytical Chemistry, which presents an innovative use of magnetic beads. Researchers from the Osaka Prefecture University at Japan have proposed the synthesis of magnetic microbeads covered with a smooth gold layer that are used for the electrochemical detection of streptavidin (1). The synthesis, which is deeply described in the manuscript, consists of three well defined steps. First of all, the magnetic beads are introduced in a colloidal gold dispersion containing Au-nanoparticles (Au-NPs). Thanks to the opposite zeta potential of both materials (microbeads are negatively charged while Au-NPs present a positive charge), their assembly takes place by electrostatic interactions. However, the Au-NPs are not connected to each other and therefore the electrical resistance of the microbeads is too high. In a second step, the modified microbeads are dispersed in an aqueous medium containing HAuCl 4 as
Read more

Rotating Disk Sorptive Extraction

By -
Image
by Prof. Dr. Pablo Richter, Department of Inorganic and Analytical Chemistry, Faculty of Chemical and Pharmaceutical Sciences, University of Chile. The modern trends in analytical chemistry promote efficiency and green technology in sample preparation. In this context, our research team developed a new technique in 2009 that is capable of extracting pollutants from liquid samples on a rotating PTFE disk with one surface coated with an extraction phase [1]. The disk has embedded a miniature magnetic rod, which allows rotation. We have termed this procedure rotating-disk sorptive extraction (RDSE). RDSE is currently available in two configurations. In the classic version (Figure 1), the extraction phase is a polymeric film adhered to one side of the PTFE disk (configuration 1). In this configuration, polydimethylsiloxane (PDMS), nylon and octadecyl (C18) have been used as the sorptive material for the extraction of low-polarity analytes (Log Kow between 3 and 7) [1-12]. However
Read more