Abstract

A validated method for preconcentration and determination of nateglinide in plasma was developed using vortex-assisted dispersive liquid–liquid microextraction. Different variables that affect extraction efficiency were studied and optimized, including type and volume of extractant, type and volume of disperser, pH of diluent, salt addition effect, centrifugation and vortex time. Nateglinide was extracted using 30 μL of 1-octanol as an extractant and 200 μL of methanol as a disperser. The enrichment factor reached 330 under the optimum conditions. High-performance liquid chromatography/ultraviolet was used for detection using phosphate buffer (pH 2.5, 10 mM): acetonitrile (45:55, v/v) as a mobile phase at a flow rate of 1 mL/min. The method was linear over the range of 50–20,000 ng/mL with a limit of detection of 15 ng/mL (signal-to-noise ratio = 3). Intra- and inter-day precision had %relative standard deviation <6% (n = 3) and the %recoveries were found to be between 102.5 and 105.9%. The proposed method is simple, sensitive, eco-friendly, cost-effective and powerful for microextraction of nateglinide from human plasma samples.

中文翻译：

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涡流辅助分散液微萃取与去蛋白结合使用HPLC / UV测定人血浆中那格列奈

摘要

使用涡流辅助分散液-液微萃取技术开发了一种有效的血浆中那格列奈预浓缩和测定方法。研究和优化了影响萃取效率的不同变量，包括萃取剂的类型和体积，分散剂的类型和体积，稀释剂的pH值，加盐效果，离心作用和涡旋时间。使用30μL的1-辛醇作为萃取剂和200μL的甲醇作为分散剂萃取那格列奈。在最佳条件下，富集因子达到330。高效液相色谱/紫外线用于检测，使用磷酸盐缓冲液（pH 2.5，10 mM）：乙腈（45:55，v / v）作为流动相，流速为1 mL / min。该方法在50–20范围内是线性的，000 ng / mL，检出限为15 ng / mL（信噪比= 3）。日内和日间精度的相对标准偏差百分比<6％（n  = 3），回收率％在102.5和105.9％之间。所提出的方法简单，灵敏，生态友好，具有成本效益，并且能够从人血浆样品中微量提取那格列奈。