Novel generation of deep eutectic solvent as an acceptor phase in three-phase hollow fiber liquid phase microextraction for extraction and preconcentration of steroidal hormones from biological fluids.

In this study, a novel generation of deep eutectic solvents (DESs) was used as an acceptor phase in three-phase hollow fiber liquid phase microextraction (HF-LPME) based on two immiscible organic phases. It was compared with other common DESs for extraction and preconcentration of dydrogesterone (DYD) and cyproterone acetate (CPA) from urine and plasma samples. The extracted analytes were analyzed by high performance liquid chromatography with UV-vis detector (HPLC-UV). This phosphonium based DES due to low volatility, low price and multifunctionality introduced itself as worthy next generation of acceptor phase in HF-LPME. The factors affected on extraction efficiency of the analytes were investigated and optimized. The performance of the proposed method was studied in terms of linear ranges (LRs from 1 to 500µgL-1 with R2 ≥ 0.9946), precision (RSD% ≤ 6.3) and limits of detection (LODs in the range of 0.5-2µgL-1). Under the optimized conditions, preconcentration factors in the range of 187-428 were obtained. Finally, the method was applied to the analysis of DYD and CPA in human urine and plasma samples and desirable results were obtained.

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.

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.

Dydrogesterone: metabolism in animals.

The metabolic pattern of dydrogesterone was investigated in the rat, dog, mouse, rabbit and rhesus monkey. The drug was administered orally in 3H-labelled form. Following enzymatic hydrolysis of conjugates the radioactive metabolites were extracted from the urine, and in rat and dog also from bile. The separation method used for the development of the metabolite patterns was reversed-phase high performance liquid chromatography. Dydrogesterone and 4 derivatives, known or suspected to be metabolites, were used as marker substances. In all the species a substantial portion of the urinary or biliary radioactivity was too polar to be extracted, or it was not resolved in the chromatographic system used. The radioactivity which did develop into a pattern coincided with two or more of the marker substances. Only in the monkey, the pattern contained a peak of some substance which did not coincide with any marker. The urinary patterns of rat, dog, and mouse differed substantially, from each other as well as from those of rabbit and monkey. The patterns for the latter two animals showed certain similarities, both to each other and to the human urinary pattern as reconstructed from previous studies. It is concluded that with regard to the metabolic fate of dydrogesterone, the rabbit resembles man more than does any other species.

Dydrogesterone: metabolism in man.

An investigation of the urinary metabolites of the oral progestational agent dydrogesterone in healthy women of childbearing age is reported. The drug was administered in 3H-labelled form and the urine of the first 8 h, containing on average 38% of the radioactivity administered, was used as the source of the metabolites. It was fortified with urine collected during the first 8 h of a similar study with nonlabelled dydrogesterone. After enzymatic hydrolysis of conjugated metabolites, 43 different chemical species were isolated by means of extraction, followed by column and thin layer chromatography. Three of these metabolites, constituting about 70% of the urinary radioactivity, were positively identified as 20 alpha-hydroxy-9 beta, 10 alpha-pregna-4, 6-diene-3-one (52%), 21-hydroxy-9 beta, 10 alpha-pregna-4, 6-diene-3, 20-dione (18%) and 16 alpha-hydroxy-9 beta, 10 alpha-4, 6-diene-3, 20-dione (1%). Of the remainder, 20 (13%) were tentatively characterized as various products of oxidative attack, all probably having the 4, 6-diene-3-one configuration intact. It is concluded that the 4, 6-diene-3-one configuration is metabolically stable in combination with the 9 beta, 10 alpha configuration. This finding may explain why dydrogesterone, in contrast no progesterone, is orally effective, and lacks estrogenic properties.