Department of Chemistry, Faculty of Science, Urmia University, Urmia, Iran.
J Sep Sci. 2011 Nov;34(21):2933-9. doi: 10.1002/jssc.201100520. Epub 2011 Oct 4.
A simple, rapid, and efficient method, dispersive liquid-liquid microextraction (DLLME) coupled with high-performance liquid chromatography-fluorescence detector, has been developed for the determination of guaifenesin (GUA) enantiomers in human urine samples after an oral dose administration of its syrup formulation. Urine samples were collected during the time intervals 0-2, 2-4, and 4-6 h and concentration and ratio of two enantiomers was determined. The ratio of R-(-) to S-(+) enantiomer concentrations in urine showed an increase with time, with R/S ratios of 0.66 at 2 h and 2.23 at 6 h. For microextraction process, a mixture of extraction solvent (dichloromethane, 100 μL) and dispersive solvent (THF, 1 mL) was rapidly injected into 5.0 mL diluted urine sample for the formation of cloudy solution and extraction of enantiomers into the fine droplets of CH(2)Cl(2). After optimization of HPLC enantioselective conditions, some important parameters, such as the kind and volume of extraction and dispersive solvents, extraction time, temperature, pH, and salt effect were optimized for dispersive liquid-liquid microextraction process. Under the optimum extraction condition, the method yields a linear calibration curve in the concentration range from 10 to 2000 ng/mL for target analytes. LOD was 3.00 ng/mL for both of the enantiomers.
建立了一种简单、快速、高效的分散液相微萃取（DLLME）与高效液相色谱-荧光检测法联用，用于测定人尿样中愈创甘油醚（GUA）对映体在口服糖浆制剂后的浓度和对映体比例。在 0-2、2-4 和 4-6 h 的时间间隔内收集尿样，并测定两种对映体的浓度和比例。尿中 R-（-）对映体与 S-（+）对映体浓度的比值随时间增加，2 h 时 R/S 比值为 0.66，6 h 时 R/S 比值为 2.23。对于微萃取过程，将萃取溶剂（二氯甲烷，100 μL）和分散溶剂（THF，1 mL）的混合物快速注入 5.0 mL 稀释的尿样中，形成浑浊溶液，并将对映体萃取到二氯甲烷的细小液滴中。在优化 HPLC 对映选择性条件后，对分散液相微萃取过程中的一些重要参数（如萃取和分散溶剂的种类和体积、萃取时间、温度、pH 值和盐效应）进行了优化。在最佳萃取条件下，该方法在 10-2000ng/mL 范围内对目标分析物呈线性校准曲线。两种对映体的检出限均为 3.00ng/mL。
