Effervescence-Assisted Microextraction: One Decade of Developments

 

A decade ago, our research group introduced the concept of effervescence-assisted microextraction. The first approach of this alternative consisted of a micrometric sorbent (OASIS-HLB) compressed in a tablet along with a carbon dioxide source (sodium carbonate) and a proton donor (sodium dihydrogen phosphate) [1]. The tablet is then placed on a syringe, and an aqueous sample is drawn. Once the sample enters in contact with the tablet, an effervescent reaction occurs, and the sorbent is efficiently dispersed by the CO₂ bubbles formed. Later, the technique was challenged with a difficult-to-disperse nanometric sorbent, unmodified multi-walled carbon nanotubes (MWCNTs) [2]. In this second adaptation, the nanotubes are compressed along with the effervescence precursors in a tablet format, and as occurs with many pharmaceutical applications, dropped in a glass containing a large aqueous sample volume (100 mL) and effervescent reaction takes place. The in-situ generated gas can disperse the sorbent efficiently without any external energy source. Finally, our last proposal took the same principle but applied to a liquid extractant (1-octanol) [3]. In this scenario, the CO₂ source (sodium carbonate) is previously dissolved in the aqueous sample, whereas the proton donor (acetic acid) is mixed with the liquid extractant). To assist the solvent recovery, it is pre-mixed with magnetic nanoparticles (MNPs), once the effervescence reaction finishes, the solvent can interact with the hydroxyl groups of the MNPs surface and collected using an external magnet.

The philosophy behind these approaches is the simplification of sample treatment procedures, as it is a major trend in our research group. The independence of external energy sources to achieve efficient extractant dispersion (such as vortex agitation or ultrasound irradiation) or disperser solvent improves the applicability and set-up the tone for greener microextraction alternatives [4].

In ten years, a myriad of different applications for this basic idea has been published. From solid phase techniques using innovative sorbents such as β-cyclodextrin/attapulgite composites [5] or crown ethers [6] in tablet formats to liquid phase approaches using ionic liquids [7], fatty acids [8] or Deep Eutectic Solvents [9].

The versatility of the effervescence as dispersant force in microextraction can be highlighted by the very different matrices (and analytes) to which it has been applied. These include water samples with different pollutants (including organic pollutants and heavy metal ions); food matrices with metal ions, endocrine disruptors, and other contaminants (including meat, seafood juices or honey) or biofluids for drug and metabolite detection (including urine, plasma or serum).

Considering all the applications of this concept, our research group recently published an in-depth review of the most relevant aspects of effervescent-based methodologies from a Green Analytical Chemistry perspective. In this publication, the interested reader can find a collection of references encompassing ten years of exciting papers. We focused on highlighting the possibilities of effervescence in different formats. Moreover, we humbly summarise and discuss these applications, amazed about how far a simple idea can be taken [10].

References:

1.        Lasarte-Aragonés, G.; Lucena, R.; Cárdenas, S.; Valcárcel, M. Effervescence-assisted dispersive micro-solid phase extraction. J. Chromatogr. A 2011, 1218.

2.        Lasarte-Aragonés, G.; Lucena, R.; Cárdenas, S.; Valcárcel, M. Effervescence-assisted carbon nanotubes dispersion for the micro-solid-phase extraction of triazine herbicides from environmental waters. Anal. Bioanal. Chem. 2013, 405.

3.        Lasarte-Aragonés, G.; Lucena, R.; Cárdenas, S.; Valcárcel, M. Effervescence assisted dispersive liquid-liquid microextraction with extractant removal by magnetic nanoparticles. Anal. Chim. Acta 2014, 807.

4.        Armenta, S.; Garrigues, S.; de la Guardia, M. The role of green extraction techniques in Green Analytical Chemistry. TrAC Trends Anal. Chem. 2015, 71, 2–8.

5.        Yang, X.; Zhang, P.; Li, X.; Hu, L.; Gao, H.; Zhang, S.; Zhou, W.; Lu, R. Effervescence-assisted β-cyclodextrin/attapulgite composite for the in-syringe dispersive solid-phase extraction of pyrethroids in environmental water samples. Talanta 2016, 153, 353–359.

6.        Hu, Y.-H.; Wang, Q.-Y.; Ye, L.-H.; Yang, J.; Dong, X.; Zheng, H.; Zhou, J.; Cao, J. Effervescent salt and crown ether-assisted matrix solid-phase dispersion extraction of coumarins from Cortex fraxini. Ind. Crops Prod. 2019, 141, 111752.

7.        Bamorowat, M.; Mogaddam, M.R.A.; Farajzadeh, M.A. Development of an ultrasonic-assisted and effervescent tablet-assisted dispersive liquid–liquid microextraction based on ionic liquids for analysis of benzoylurea insecticides. Int. J. Environ. Anal. Chem. 2020, 1–15.

8.        Hemmati, M.; Rajabi, M. Switchable fatty acid based CO2-effervescence ameliorated emulsification microextraction prior to high performance liquid chromatography for efficient analyses of toxic azo dyes in foodstuffs. Food Chem. 2019, 286, 185–190.

9.        Ghorbani Ravandi, M.; Fat’hi, M.R. Green effervescence assisted dispersive liquid–liquid microextraction based on a hydrophobic deep eutectic solvent for determination of Sunset Yellow and Brilliant Blue FCF in food samples. New J. Chem. 2018, 42, 14901–14908.

10.      Lasarte-Aragonés, G.; Lucena, R.; Cárdenas, S. Effervescence-Assisted Microextraction—One Decade of Developments. Mol.  2020, 25.