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Protocol for solid-phase microextraction method development

Abstract

Solid-phase microextraction (SPME) is a sample preparation method developed to solve some of the analytical challenges of sample preparation as well as sample introduction and integration of different analytical steps into one system. Since its development, the utilization of SPME has addressed the need to facilitate rapid sample preparation and integrate sampling, extraction, concentration and sample introduction to an analytical instrument into one solvent-free step. This achievement resulted in fast adoption of the technique in many fields of analytical chemistry and successful hyphenation to continuously developing sophisticated separation and detection systems. However, the facilitation of high-quality analytical methods in combination with SPME requires optimization of the parameters that affect the extraction efficiency of this sample preparation method. Therefore, the objective of the current protocol is to provide a detailed sequence of SPME optimization steps that can be applied toward development of SPME methods for a wide range of analytical applications.

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Figure 1
Figure 2: Total ion current (TIC) GC–MS chromatogram illustrating the comparison of PDMS and PA coating performances for the analysis of o-xylene and 2,4-dichlorophenol in water samples.
Figure 3
Figure 4: An example of post-extraction derivatization.
Figure 5: The effect of sample temperature on the kinetics of extraction process of methamphetamine.
Figure 6
Figure 7
Figure 8: The effect of distribution constant on the equilibration time for PAHs.
Figure 9: The effect of agitation on the equilibration time for PAHs.

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Acknowledgements

The authors thank the Natural Sciences and Engineering Research Council of Canada (NSERC) for their financial support. The authors also like to acknowledge the contribution of Dr Zhouyao Zhang to the development of fiber-SPME technique.

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Authors and Affiliations

Authors

Contributions

S.R. contributed to the development and validation of SPME methods, combined the data and wrote the protocol; H.L., T.G. and C.L.A. contributed to the SPME method optimization and validation, as well as development of theoretical principles of SPME; H.L. and T.G. provided helpful suggestions on the improvement of the protocol; and J.P. developed the SPME concept and the ideas on optimization of SPME methods and supervised the projects.

Corresponding author

Correspondence to Janusz Pawliszyn.

Supplementary information

Supplementary Figure 1

The graphical illustration of commercially available fibre-SPME device for the performance of manual SPME procedures. Manual fibre holder (a). Fibre assembly with built-in fibre inside the needle coated with 1 or 2 cm long polymeric coating (b). (JPG 123 kb)

Supplementary Figure 2

Illustration of SPME process. Legend: Kes - fibre coating/sample matrix distribution constant, Ve - fibre coating volume, Vs - sample volume, Co - initial concentration of analyte in the sample. (JPG 123 kb)

Supplementary Figure 3

The graphical illustration of the DI-SPME procedure. The sample and a magnetic stir bar are placed in a vial, which is then sealed with a septum-type cap. The vial is placed on the magnetic stirrer (a). The SPME needle pierces the vial septum (b). The fibre coating is extended through the needle into the sample matrix (c). The fibre coating is withdrawn into the needle (d). The needle is withdrawn from the vial septum (e). Subsequent desorption of analytes into analytical instrument is performed. (JPG 378 kb)

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Risticevic, S., Lord, H., Górecki, T. et al. Protocol for solid-phase microextraction method development. Nat Protoc 5, 122–139 (2010). https://doi.org/10.1038/nprot.2009.179

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