Gjelstad Astrid, Rasmussen Knut Einar, Pedersen-Bjergaard Stig
School of Pharmacy, University of Oslo, P.O. Box 1068, Blindern, 0316 Oslo, Norway.
J Chromatogr A. 2006 Aug 18;1124(1-2):29-34. doi: 10.1016/j.chroma.2006.04.039. Epub 2006 May 11.
Twenty different basic drugs were electrokinetically extracted across a thin artificial organic liquid membrane with a 300 V d.c. electrical potential difference as the driving force. From a 300 microl aqueous sample (acidified corresponding to 10mM HCl), the drugs were extracted for 5 min through a 200 microm artificial liquid membrane of a water immiscible organic solvent immobilized in the pores of a polypropylene hollow fiber, and into a 30 microl aqueous acceptor solution of 10mM HCl inside the lumen of the hollow fiber. Hydrophobic basic drugs (logP>1.7) were effectively isolated utilizing 2-nitrophenyl octyl ether (NPOE) as the artificial liquid membrane, with recoveries up to 83%. For more hydrophilic basic drugs (logP<1.0), a mixture of NPOE and 25% (w/w) di-(2-ethylhexyl) phosphate (DEHP) was required to ensure efficient extraction, resulting in recoveries up to 75%. DEHP was expected to act as an ion-pair reagent ion-pairing the protonated hydrophilic drugs at the interface between the sample and the membrane, resulting in permeation of the interface.
以300V直流电势差为驱动力，通过薄的人工有机液膜对20种不同的碱性药物进行电动提取。从300微升的水性样品（酸化至相当于10mM HCl）中，药物通过固定在聚丙烯中空纤维孔中的200微米水不混溶有机溶剂的人工液膜提取5分钟，并进入中空纤维内腔中30微升10mM HCl的水性接受溶液。利用2-硝基苯基辛基醚（NPOE）作为人工液膜有效地分离疏水性碱性药物（logP>1.7），回收率高达83%。对于亲水性更强的碱性药物（logP<1.0），需要NPOE和25%（w/w）磷酸二（2-乙基己基）酯（DEHP）的混合物以确保有效提取，回收率高达75%。预计DEHP作为离子对试剂，在样品与膜之间的界面处与质子化的亲水性药物形成离子对，从而导致界面渗透。
