Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
J Chromatogr A. 2013 Jul 5;1297:12-6. doi: 10.1016/j.chroma.2013.04.082. Epub 2013 May 8.
Electroenhanced solid-phase microextraction (EE-SPME) method with gas chromatographic mass spectrometric analysis was investigated for the determination of methamphetamine in urine sample with commercial fibers. In this approach, commercial SPME fibers were used in direct immersion mode with an applied potential to extract methamphetamine. EE-SPME was more effective in the extraction compared to conventional SPME (i.e. application of potential). The method was simple to use, and avoided the need for alkalization and derivatization of methamphetamine. Experimental conditions were optimized to achieve better extraction performance. Various conditions including applied potential, sample pH, extraction and desorption time were investigated. Based on the optimized conditions, EE-SPME achieved a higher enrichment factor of 159-fold than conventional SPME. The calibration plot under the best selected parameters was linear in the range of 0.5-15ng/mL (r=0.9948). The feasibility of EE-SPME was demonstrated by applying it to the analysis of human urine samples. The limit of detection of methamphetamine was 0.25ng/mL with a satisfactory relative standard deviation of 6.12% (n=3) in human urine.
采用气相色谱-质谱联用分析的电化学增强固相微萃取（EE-SPME）方法，以商业纤维研究尿液样品中甲卡西酮的测定。在此方法中，采用施加电位的直接浸入模式使用商业 SPME 纤维萃取甲卡西酮。与传统的 SPME 相比，EE-SPME 萃取更有效（即施加电位）。该方法简单易用，避免了甲卡西酮的碱化和衍生化。优化了实验条件以实现更好的萃取性能。研究了各种条件，包括施加的电位、样品 pH 值、萃取和解析时间。基于优化条件，EE-SPME 实现了比传统 SPME 高 159 倍的更高富集因子。在最佳选择参数下，校准曲线在 0.5-15ng/mL 范围内呈线性（r=0.9948）。通过将其应用于人尿样分析证明了 EE-SPME 的可行性。甲卡西酮的检测限为 0.25ng/mL，人尿中相对标准偏差为 6.12%（n=3），令人满意。
