Federal University of Uberlândia, Institute of Chemistry, 38400-902, Uberlândia, MG, Brazil.
Federal University of Uberlândia, Institute of Chemistry, 38400-902, Uberlândia, MG, Brazil.
Talanta. 2020 Sep 1;217:120987. doi: 10.1016/j.talanta.2020.120987. Epub 2020 Apr 10.
Cocaine is one of the most frequently used illicit drug in the world. Therefore, the development of simple and fast methods for the detection of cocaine and common adulterants, diluents and impurities are extremely important in forensic investigations. The present study describes, for the first time, a method based on capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-CD) for the rapid (2.5 min) and simultaneous quantification of cocaine, levamisole, lidocaine, carbonate, borate, chloride, nitrate, nitrite and sulphate. In the experiment, anions were separated in co-electroosmotic mode and cations in counter-electroosmotic mode employing a buffer solution composed by 10.0 mmol L TAPS, 12 mmol L NaOH and 0.2 mmol L CTAB as the background electrolyte (pH = 8.8). The developed CE method demonstrated some interesting analytical characteristics such as: (i) a simple sample pretreatment step (only dilution in water and filtering), (ii) high-throughput screening (24 injections h), (iii) proper recovery values (between 72 and 118%), and (iv) an inter-day precision of less than 7% for all analytes. The procedure was successfully applied in the analysis of seized cocaine samples collected by the Integrated Forensics Post (PPI) of the Minas Gerais Civil Police (Uberaba, Minas Gerais State, Brazil), during the year of 2018.
可卡因是世界上使用最频繁的非法药物之一。因此，开发简单、快速的方法来检测可卡因和常见的掺杂物、稀释剂和杂质，对于法医学调查至关重要。本研究首次描述了一种基于毛细管电泳与电容耦合非接触式电导检测（CE-CD）的方法，用于快速（2.5 分钟）和同时定量检测可卡因、左旋咪唑、利多卡因、碳酸盐、硼酸盐、氯化物、硝酸盐、亚硝酸盐和硫酸盐。在实验中，阴离子在电渗流模式下分离，阳离子在反电渗流模式下分离，使用由 10.0 mmol L TAPS、12 mmol L NaOH 和 0.2 mmol L CTAB 组成的缓冲溶液作为背景电解质（pH = 8.8）。所开发的 CE 方法具有一些有趣的分析特点，例如：（i）简单的样品预处理步骤（仅稀释在水中并过滤），（ii）高通量筛选（24 次/小时），（iii）适当的回收率值（在 72%至 118%之间），以及（iv）所有分析物的日内精密度均小于 7%。该程序成功应用于 2018 年米纳斯吉拉斯州民事警察综合取证站（PPI）收集的缴获可卡因样品的分析。
