Hollow-fiber liquid phase microextraction LPME

Bardstu, K.F., Ho, T.S., Rasmussen, K.E., Pedersen-Bjergaard, S. and Jonsson, J.A. (2007) Supported liquid membranes in hollow fiber liquid-phase microextraction (LPME) — Practical considerations in the three-phase mode. Journal of Separation Science, 30, 1364. 

Bardstu KF, Ho TS, Rasmussen KE, Pedersen-Bjergaard S, Jonsson jA. Supported hquid membranes in hollow fiber liquid-phase microextraction (LPME). Practical considerations in the 3-phase mode. J Sep Sci 2007 30 1364-1370. 

HFs have been used successfully for preconcentration in chemical analysis. One technique termed hollow-fiber liquid-phase microextraction (HF-LPME) involves filling the pores of an inert HF material (commonly polypropylene) with an organic phase containing a carrier in a similar way to the manufacturing of SLMs. The fiber is then dipped into an aqueous sample solution, and the analyte is transported across the HF to a small volume of receiver phase in the lumen of the HF that is subsequently analyzed [41,42]. 

Recently, Psillakis et al. " have developed a liquid phase microextraction (LPME) technique using a hollow fiber membrane in conjunction with GC-MS for the extraction and analysis of phthalates. The resulting method was validated and compared with SPME. Both techniques showed comparable performance and were considered suitable for trace analysis of phthalates in water. 

Pedersen-Bjergaard S, Rasmussen KE, Jonsson jA. Liquid-phase microextraction (LPME) utilizing porous hollow fibers. In Pawhszyn J, Lord H, eds. Handbook of Sample Preparation. Hoboken, NJ John Whey Sons 2010 pp. 125-148. 

In liquid-phase microextraction (LPME), a liquid membrane is used to enrich and isolate analytes from a complex sample. The liquid membrane, which is immiscible with water and the sample matrix, is immobilized in the pores of a porous hollow fiber. Such a liquid membrane is referred to as a supported liquid membrane (S LM). Immobilization of the SLM is achieved by simply dipping the hollow fiber in an organic solvent allowing the pores to be filled. Figure 9.11 shows a schematic representation of LPME. 

FIGURE 12.2 Hollow-fiber devices for membrane extraction, (a) Hollow-fiber loops for equilibrium extraction redrawn after Liu et al. (From Liu, J.-F., Jbnsson, J.A., and Mayer, P., Anal. Chem., 77, 4800, 2005.) (b) Liquid-phase microextraction after Pedersen-Bjergaard and Rasmussen. (From Grpuhaug Halvorsen, T., Pedersen-Bjergaard, S., Reubsaet, J.L.E., and Rasmussen, K.E., J. Sep. ScL, 24, 615, 2001. With permission.) (c) Syringe-based hollow fiber LPME. (Erom Zhao, L. and Lee, H.K., Anal. Chem., 74, 2486, 2002. Copyright 2002 American Chemical Society. With permission.)... 

Ramos Paydn M, Bello L6pez mA, Fernandez-Torres R, Callejon Mochon M, Gomez Ariza JL. Application of hollow fiber-based liquid-phase microextraction (HF-LPME) for the determination of acidic pharmaceuticals in wastewaters. Talanta 2010 82 854-858. 

Ramos Payan M, Bello Lopez mA, Femandez-Torres R, Gonzalez JAO, Callejdn Mochon M. Hollow fiber-based liquid phase microextraction (HF-LPME) as a new approach for the HPLC determination of fluoroquinolones in biological and environmental matrices. J Pharm Biomed Anal 2011 55 332-341. 

LLE, liquid-liquid extraction MAE, microwave-assisted extraction SEE, solid-phase extraction SPME, solid-phase microextraction LPME, liquid-phase microextraction SOME, single-drop microextraction D-LLLME, dynamic liquid-liquid-liquid microextraction SEE, supercritical fluid extraction MIP, molecularly imprinted polymers sorbent SPMD, device for semipermeable membrane extraction PDMS, polydimethylsiloxane coated fiber PA, polyacrylate coated fiber CW-DMS, Carbowax-divinylbenzene fiber PDMS-DVB, polydimethylsiloxane divinylbenzene fiber CAR-PDMS, Carboxen-polydimethylsiloxane coated fiber DVB-CAR-PDMS, divinylbenzene Carboxen-polydimethylsiloxane coated fiber CW-TPR, Carbowax-template resin HS-SPME, headspace solid-phase microextraction MA-HS-SPME, microwave-assisted headspace-solid-phase microextraction HEM, porous hollow fiber membrane PEl-PPP, polydydroxylated polyparaphenylene. 

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