Stir bar sorptive dispersive microextraction mediated by magnetic nanoparticles

By -
We all are familiar with stir bar sorptive extraction (SBSE) and dispersive methodologies in this context. The advantages of both techniques are also well known and a deep research is being carried out to characterize new sorbent phases which improve the efficiency and open up the application field of these microextraction techniques.

Research teams from the University of Valencia at Spain and Ioannina at Greece have joined their deep knowledge in dispersive techniques to bring us a very elegant combination of stir bar sorptive dispersive microextraction mediated by magnetic nanoparticles (SBSEDµE) (1). The main advantage of the proposed methodology is clear as it permits the use of a wider variety of sorbent phases while maintaining the advantages of agitation and simplicity of sorbent recovery provided by the magnetic element.

The sorbent is either coated on the stir bar or dispersed in the sample matrix depending on the stirring speed. The general procedure is shown in Figure 1. In a first step, the bar containing the attached magnetic nanoparticles (MNPs) is introduced into the sample. Then, the bar is stirred at high velocities inducing the detachment of the MNPs from the bar into the sample, the extraction of the analytes taking place. The continuous reduction of the stirring velocity induces again the attachment of the MNPs on the bar simplifying the final elution step.
 
Figure 1. General porcedure of stir bar sorptive dispersive microextraction
The analytical problem selected for the evaluation of this novel approach is the determination of organic UV filters in seawaters. For this aim, oleic acid-coated cobalt ferrite MNPs was selected as sorbent material. They have carried out a rigorous study to properly characterize and evaluate the potential of SBSEDµE.

From this blog, we congratulate our colleagues for being the first in envisage the potential of the direct combination of these two microextraction concepts. As usual, the simplicity of the approach is its key strength.

Enjoy the reading!!

Reference:
(1) Development of stir bar sorptive-dispersive microextraction mediated by magnetic nanoparticles and its analytical application to the determination of hydrophobic organic compounds in aqueous media. Link to the article

Comments

  1. 陈氏博客August 20, 2015 at 7:53 PM

    I wonder what's the advantages of the proposed SBSEDµE, when compared with magnetic solid phase extraction(MSPE).

    ReplyDelete

Post a Comment

Popular posts from this blog

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

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

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