Composites of silver nanoparticles and polyaniline for MEPS

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The combination of highly efficient sorbent with commercially available extraction devices is the best way to consolidate microextraction techniques in routine laboratories. The potential of nanoparticles in this context is undeniable. In this regard, our colleagues of the Sharif University of Technology (Tehran, Iran) have evaluated the potential of a novel nanocomposite for microextraction in packed syringe (1). The new sorbent is based on silver nanoparticles/polyaniline (Ag NPs/PANI) and it was prepared by using interfacial polymerization.

The procedure is rather simple and it is performed in an aqueous/organic biphasic system being the Ag NPs/PANI nanocomposite formed in the interface. The evolution of the reaction can be easily followed by the color change of the mixture which starts with a free color at the interface which becomes darker in the organic phase and eventually stop changing, indicating the reaction completion. After 24 h of ageing, the composite can be separated from the liquid phase. The microscopic examination of the solid corroborates the presence of the metallic nanoparticles acting as nucleation centers of polymerization. On the other hand, the polymer limits particle size distribution within the desired limits.

The nanocomposite was packed into the MEPS units and all the variables affecting to the extraction process were studied. The determination of furosemide in human urine was selected as model analytical problem. Among all the variables, the draw-ejects cycles can be highlighted owing to its positive influence in method sensitivity.

Concerning the analytical features, the most relevant result is the good preconcentration factor provided by the technique. Finally, the authors compare their data with previously reported one and also apply the optimized MEPS procedure to the analysis of real human urine samples.

The original manuscript, published in Chromatographia, described in depth all these aspects. We strongly recommend its reading.

References:

(1) Silver Nanoparticles–Polyaniline Nanocomposite for Microextraction in Packed Syringe. Link to the article

Additional information:
If you are interested on the synthesis of AgNPs/PANI, you can obtain additional information from the article entitled "Synthesis and characterization of silver nanoparticles embedded in polyaniline nanocomposite", published in Advanced Material Letters. The article was authored by Wankhede, Kondawar, Thakare and More in 2013 and it is open access. Link to the article


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