Introduction: Verapamil (Verap) is an antidysrhythmic agent and a calcium channel blocker, indicated for angina, hypertension, supraventricular arrhythmias, and migraine.

Objective: Drug monitoring plays a critical role in patient survival. In order to prevent the onset of drug toxicity, trace levels of this drug should be determined.

Methods: For this reason, solvent bar microextraction technique coupled with high-performance liquid chromatography was implemented.

Results: Under optimum condition, verapamil was micro-extracted from a donor solution (pH=11) to an acceptor solution (pH=3.2). It was transferred through n-octanol as the organic solvent, which was impregnated in the pores of the hollow fiber. Salt addition (30%) had the major effect on the efficiency of the method. Interaction of time (65 min), temperature (25°C), and stirring rate (818 rpm) had a significant effect too. It all resulted in a limit of detection and quantification of 15 ng mL-1 and 50 ng mL-1, respectively. The relative standard deviations of analysis were 4.9% within a day (n=3) and 5.7% between days (n=9). The calibration curves represented good linearity for urine and plasma samples with coefficient estimations higher than 0.99 with a linearity range of 50-5000 ng mL-1. The relative standard deviation for intra- (n=3) and inter-(n=9) day was 4.2% and 5.7%, respectively.

Conclusion: It could be concluded that the application of this method for dose monitoring can be done at hospital and healthcare facilities.

简介：维拉帕米（Verap）是一种抗心律失常药和钙通道阻滞剂，适用于心绞痛，高血压，室上性心律失常和偏头痛。

目的：药物监测在患者生存中起着至关重要的作用。为了防止药物毒性的发作，应确定该药物的痕量水平。

方法：为此，实施了溶剂棒微萃取技术结合高效液相色谱法。

结果：在最佳条件下，维拉帕米从供体溶液（pH = 11）微萃取到受体溶液（pH = 3.2）。将其通过正辛醇作为有机溶剂转移，将其浸渍在中空纤维的孔中。加盐（30％）对方法的效率有重大影响。时间（65分钟），温度（25°C）和搅拌速度（818 rpm）之间的相互作用也有显着影响。所有这些导致检测和定量的极限分别为15 ng mL-1和50 ng mL-1。分析的相对标准偏差在一天之内为4.9％（n = 3），在一天之间为5.7％（n = 9）。校准曲线代表尿液和血浆样品的良好线性，系数估计值高于0.99，线性范围为50-5000 ng mL-1。

结论：可以得出结论，该方法在剂量监测中的应用可以在医院和医疗机构进行。