title: Development of a microfluidic-chip system for liquid-phase microextraction based on two immiscible organic solvents for the extraction and preconcentration of some hormonal drugs.
abstract: In the present study, for the first time, an on-chip liquid phase microextraction (LPME) coupled with high performance liquid chromatography was introduced for the analysis of levonorgestrel (Levo), dydrogesterone (Dydo) and medroxyprogesterone (Medo) as the model analytes in biological samples. The chip-based LPME set-up was composed of two polymethyl methacrylate (PMMA) plates with microfabricated channels and a microporous membrane sandwiched between them to separate the sample solution and acceptor phase. These channels were used as a flow path for the sample solution and a thin compartment for the acceptor phase, respectively. In this system, two immiscible organic solvents were used as supported liquid membrane (SLM) and acceptor phase, respectively. During extraction, the model analytes in the sample solution were transported through the SLM (n-dodecane) into the acceptor organic solvent (methanol). The new set-up provided effective and reproducible extractions using low volumes of the sample solution. The effective parameters on the extraction efficiency of the model analytes were optimized using one variable at a time method. Under the optimized conditions, the new set-up provided good linearity in the range of 5.0-500µgL(-1) for the model analytes with the coefficients of determination (r(2)) higher than 0.9909. The relative standard deviations (RSDs%) and limits of detection (LODs) values were less than 6.5% (n=5) and 5.0µgL(-1), respectively. The preconcentration factors (PFs) were obtained using 1.0mL of the sample solution and 20.0µL of the acceptor solution higher than 19.9-fold. Finally, the proposed method was successfully applied for the extraction and determination of the model analytes in urine samples.
authors: Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran.
authors: Yousef Abdossalami
authors: YA
authors: Asl
authors: Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran. Electronic address: yyamini@modares.ac.ir.
authors: Yadollah
authors: Y
authors: Yamini
authors: Department of Analytical Chemistry, Faculty of Chemistry, K.N. Toosi University of Technology, Tehran, Iran.
authors: Shahram
authors: S
authors: Seidi
mesh_terms: D000328:Adult; D000473:Alkanes / Q000737:chemistry*; D004394:Dydrogesterone / Q000652:urine*; D005260:Female; D006801:Humans; D056656:Lab-On-A-Chip Devices; D016912:Levonorgestrel / Q000652:urine*; D059627:Liquid Phase Microextraction / Q000295:instrumentation; D008525:Medroxyprogesterone / Q000652:urine*; D000432:Methanol / Q000737:chemistry*; D019904:Polymethyl Methacrylate / Q000737:chemistry; D012997:Solvents / Q000737:chemistry*
chemical_list: D000473:Alkanes; D012997:Solvents; C007548:n-dodecane; D016912:Levonorgestrel; D019904:Polymethyl Methacrylate; D004394:Dydrogesterone; D008525:Medroxyprogesterone; D000432:Methanol
keywords: Dydrogesterone; Levonorgestrel; Medroxyprogesterone; Microfluidic chip; Two immiscible organic solvents