The aim of this study was to develop a method for the determination of the Val-Leu-Pro-Val-Pro-Arg (VLPVPR) antihypertensive peptide in human plasma based on a carrier-mediated three-phase solvent bar microextraction (SBME) coupled with a high performance liquid chromatography diode array detector (HPLC-DAD). For this purpose, the SBME was performed under various operating conditions to optimize the parameters including the pH of the donor and receiving phases, sodium chloride (NaCl) concentration in the receiving phase, carrier concentration, agitation rate, and extraction time. A high enrichment effect was achieved when the pH of the donor phase (i.e., sample solution) was 12, the pH of the receiving phase was 2, the NaCl concentration in the receiving phase was 2 mol L⁻¹, the carrier concentration was 15% (w/v), the agitation rate was 700 rpm, and the extraction time was 60 min. Furthermore, the analytical characteristics of the SBME-HPLC method including the linear range (0.2–20 μg mL⁻¹), the detection limit (68.5 ng mL⁻¹), the precision (RSD = 1.1%, n = 5), and the enrichment factor (27.5 ± 0.65) were evaluated in human plasma. The results showed that the method was suitable for the determination of VLPVPR antihypertensive peptide in bio-fluid samples.

中文翻译：

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载体介导的溶剂棒微萃取结合HPLC-DAD定量分析人血浆中的亲水性降压肽VLPVPR

这项研究的目的是开发一种基于载体介导的三相溶剂棒微萃取（SBME）偶联测定人血浆中Val-Leu-Pro-Val-Pro-Arg（VLPVPR）抗高血压肽的方法配有高效液相色谱二极管阵列检测器（HPLC-DAD）。为此，在各种操作条件下执行SBME，以优化参数，包括供体和接收相的pH值，接收相中的氯化钠（NaCl）浓度，载体浓度，搅拌速率和萃取时间。当供体相（即样品溶液）的pH为12，接收相的pH为2，接收相中的NaCl浓度为2 mol L ^-1时，可实现较高的富集效果。，载体浓度为15％（w / v），搅拌速度为700rpm，提取时间为60分钟。此外，SBME-HPLC方法的分析特性包括线性范围（0.2–20μgmL ^-1），检测限（68.5 ng mL ^-1），精密度（RSD = 1.1％，n = 5）和在人体血浆中评估富集因子（27.5±0.65）。结果表明，该方法适用于生物流体样品中VLPVPR降压肽的测定。