TY - JOUR
T1 - Kinetic electro membrane exctraction under stagnant conditions - Fast isolation of drugs from untreated human plasma
AU - Eibak, Lars Erik Eng
AU - Gjelstad, Astrid
AU - Rasmussen, Knut Einar
AU - Pedersen-Bjergaard, Stig
PY - 2010/7
Y1 - 2010/7
N2 - Amitriptyline, citalopram, fluoxetine, and fluvoxamine were isolated by electro membrane extraction (EME) from 70μl of untreated plasma (pH 7.4), through a supported liquid membrane (SLM) of 1-ethyl-2-nitrobenzene immobilized in the pores of a porous polypropylene hollow fiber, and into 30μl of 10mM HCOOH as acceptor solution inside the lumen of the hollow fiber. The driving force of the extraction was a 9V potential sustained over the SLM with a common battery, with the positive electrode placed in the plasma sample and the negative electrode placed in the acceptor solution. Extractions were performed under totally stagnant conditions with a very simple device for 1min (kinetic regime), and subsequently the acceptor solution was analyzed directly by liquid chromatography-mass spectrometry (LC-MS). Recoveries were 12, 13, 22, and 17% for fluoxetine, amitriptyline, citalopram, and fluvoxamine, respectively. Sample clean-up was comparable to reversed-phase solid-phase extraction (SPE), but EME required substantially less time than SPE. The time advantage of EME was further improved by parallel extraction of three samples (for 1min) with the same 9V battery. EME from plasma combined with LC-MS provided limits of quantification (S/N=10) in the range 0.4-2.3ng/ml, linearity in the range 1-1000ng/ml with r2-values of 0.998-0.999, and repeatability in the range 3.2-8.9% RSD in the mid-therapeutic window (100ng/ml).
AB - Amitriptyline, citalopram, fluoxetine, and fluvoxamine were isolated by electro membrane extraction (EME) from 70μl of untreated plasma (pH 7.4), through a supported liquid membrane (SLM) of 1-ethyl-2-nitrobenzene immobilized in the pores of a porous polypropylene hollow fiber, and into 30μl of 10mM HCOOH as acceptor solution inside the lumen of the hollow fiber. The driving force of the extraction was a 9V potential sustained over the SLM with a common battery, with the positive electrode placed in the plasma sample and the negative electrode placed in the acceptor solution. Extractions were performed under totally stagnant conditions with a very simple device for 1min (kinetic regime), and subsequently the acceptor solution was analyzed directly by liquid chromatography-mass spectrometry (LC-MS). Recoveries were 12, 13, 22, and 17% for fluoxetine, amitriptyline, citalopram, and fluvoxamine, respectively. Sample clean-up was comparable to reversed-phase solid-phase extraction (SPE), but EME required substantially less time than SPE. The time advantage of EME was further improved by parallel extraction of three samples (for 1min) with the same 9V battery. EME from plasma combined with LC-MS provided limits of quantification (S/N=10) in the range 0.4-2.3ng/ml, linearity in the range 1-1000ng/ml with r2-values of 0.998-0.999, and repeatability in the range 3.2-8.9% RSD in the mid-therapeutic window (100ng/ml).
KW - Former Faculty of Pharmaceutical Sciences
U2 - 10.1016/j.chroma.2010.06.018
DO - 10.1016/j.chroma.2010.06.018
M3 - Journal article
C2 - 20591437
SN - 0301-4770
VL - 1217
SP - 5050
EP - 5056
JO - Journal of Chromatography
JF - Journal of Chromatography
IS - 31
ER -