editorial on “beyond dispersive liquid–liquid microextraction” by mei-i leong, ming-ren fuh...

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Journal of Chromatography A, 1335 (2014) 1 Contents lists available at ScienceDirect Journal of Chromatography A j o ur na l ho me page: www.elsevier.com/locate/chroma Editorial Editorial on “Beyond dispersive liquid–liquid microextraction” by Mei-I Leong, Ming-Ren Fuh and Shang-Da Huang Just like solid-phase microextraction (entailing a thin layer of sorbent coated on a short length of a fused silica fiber) (late 1980s), and liquid-phase microextraction (in which the original approach involved just a drop of extractant solvent) (mid-1990s) before it, dispersive liquid–liquid microextraction (DLLME) is characterized by neat simplicity in its operation and application. The way DLLME is conducted is delightfully minimalistic: mix a water-miscible solvent and water-immiscible solvent in a syringe and inject the mixture forcefully into a water sample, and that is about it [1]. Extraction takes place almost instantaneously amidst the forma- tion of an emulsion (cloudy solution). The extract is collected after centrifugation to break up the mixture into two phases (the extract and the rest). This is where a slight complication arises: the need for centrifugation; and the use of a denser-than-water solvent to facilitate the practicality of extract collection after centrifugation. Much of the focus on DLLME subsequently has been to attempt to eliminate the need for centrifugation and obviate the use of denser- than-water (usually the undesirable chlorinated) solvents. There have been numerous approaches to this end. The elimination of the centrifugation step is important if one is desirous of automat- ing the DLLME process on a commercial autosampling system. The following Editors’ Choice review by Mei-I Leong (Macau, China), DOI of original article: http://dx.doi.org/10.1016/j.chroma.2014.02.021. and Ming-Ren Fuh and Shang-Da Huang (Taiwan), attempts to chronicle the developments in DLLME in recent years, after the first paper [1] established a very fertile area of research in sample prepa- ration. The title “Beyond dispersive liquid–liquid microextraction” was suggested by the editor, to signify the extension of the develop- ment of DLLME, beyond its basic implementation. To enable routine application of the procedure to real-world problems, more opera- tional convenience and some form of automation would be needed. We hope readers will find that the authors of the review have been able to capture the essence of taking DLLME development forward to its near- and mid-term future. Reference [1] M. Rezaee, Y. Assadi, M.R.M. Hosseini, E. Aghaee, F. Ahmadi, S. Berijani, J. Chromatogr. A 1116 (2006) 1. Hian Kee Lee Singapore, Singapore E-mail address: [email protected] Available online 13 February 2014 http://dx.doi.org/10.1016/j.chroma.2014.02.022 0021-9673/© 2014 Elsevier B.V. All rights reserved.

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Journal of Chromatography A, 1335 (2014) 1

Contents lists available at ScienceDirect

Journal of Chromatography A

j o ur na l ho me page: www.elsev ier .com/ locate /chroma

ditorial

ditorial on “Beyond dispersive liquid–liquid microextraction” byei-I Leong, Ming-Ren Fuh and Shang-Da Huang

[

Hian Kee LeeSingapore, Singapore

Just like solid-phase microextraction (entailing a thin layer oforbent coated on a short length of a fused silica fiber) (late 1980s),nd liquid-phase microextraction (in which the original approachnvolved just a drop of extractant solvent) (mid-1990s) before it,ispersive liquid–liquid microextraction (DLLME) is characterizedy neat simplicity in its operation and application. The way DLLME

s conducted is delightfully minimalistic: mix a water-miscibleolvent and water-immiscible solvent in a syringe and inject theixture forcefully into a water sample, and that is about it [1].

xtraction takes place almost instantaneously amidst the forma-ion of an emulsion (cloudy solution). The extract is collected afterentrifugation to break up the mixture into two phases (the extractnd the rest). This is where a slight complication arises: the needor centrifugation; and the use of a denser-than-water solvent toacilitate the practicality of extract collection after centrifugation.

uch of the focus on DLLME subsequently has been to attempt toliminate the need for centrifugation and obviate the use of denser-han-water (usually the undesirable chlorinated) solvents. There

ave been numerous approaches to this end. The elimination ofhe centrifugation step is important if one is desirous of automat-ng the DLLME process on a commercial autosampling system. Theollowing Editors’ Choice review by Mei-I Leong (Macau, China),

DOI of original article: http://dx.doi.org/10.1016/j.chroma.2014.02.021.

ttp://dx.doi.org/10.1016/j.chroma.2014.02.022021-9673/© 2014 Elsevier B.V. All rights reserved.

and Ming-Ren Fuh and Shang-Da Huang (Taiwan), attempts tochronicle the developments in DLLME in recent years, after the firstpaper [1] established a very fertile area of research in sample prepa-ration. The title “Beyond dispersive liquid–liquid microextraction”was suggested by the editor, to signify the extension of the develop-ment of DLLME, beyond its basic implementation. To enable routineapplication of the procedure to real-world problems, more opera-tional convenience and some form of automation would be needed.We hope readers will find that the authors of the review have beenable to capture the essence of taking DLLME development forwardto its near- and mid-term future.

Reference

1] M. Rezaee, Y. Assadi, M.R.M. Hosseini, E. Aghaee, F. Ahmadi, S. Berijani,J. Chromatogr. A 1116 (2006) 1.

E-mail address: [email protected]

Available online 13 February 2014