The differential pulse adsorptive cathodic stripping voltammetry (DP-AdsCSV) employing the hanging mercury drop electrode (HMDE) was used towards the determination of two psychotropic drugs in environmental samples. Voltammetric and experimental conditions to Clonazepam (CLO) and diazepam (DIAZ) were optimized and the methods were in-house validated. Accumulation potentials were −0.3 V to CLO and −0.6 V to DIAZ at 120 s of accumulation time. Pulse amplitude, pulse time and scan rate were 80 mV, 20 ms and 25 mV s−1 to CLO and 100 mV, 20 ms and 40 mV s−1 to DIAZ, respectively. Recovery tests were done in three different concentrations to evaluate methods’ accuracy and the results were from 88±6 to 120±13 %. In precision tests, standard deviations were lower than 15 % for both methods. Goods limits of quantification 0.65 and 0.27 μg L−1 to CLO and DIAZ respectively were achieved without pre-concentration steps such as SPE, etc. Voltammetry employing HMDE was first used for the determination of CLO and DIAZ in natural water. Natural samples were spiked and recovery tests confirmed the applicability of the methods developed. Nine samples from Parana state, Brazil, were analyzed and CLO and DIAZ values were below the limits of detection in all samples.

中文翻译：

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天然水中地西泮和氯硝西泮的测定 - 伏安法研究

采用悬汞滴电极 (HMDE) 的差分脉冲吸附阴极溶出伏安法 (DP-AdsCSV) 用于测定环境样品中的两种精神药物。对氯硝西泮 (CLO) 和地西泮 (DIAZ) 的伏安法和实验条件进行了优化，并对方法进行了内部验证。在 120 秒的累积时间，累积电位为 -0.3 V 至 CLO 和 -0.6 V 至 DIAZ。脉冲幅度、脉冲时间和扫描速率分别为 80 mV、20 ms 和 25 mV s-1 到 CLO 和 100 mV、20 ms 和 40 mV s-1 到 DIAZ。在三种不同浓度下进行回收率测试以评估方法的准确性，结果为 88±6 至 120±13%。在精密度测试中，两种方法的标准偏差均低于 15%。货物定量限为 0.65 和 0。无需预浓缩步骤（如 SPE 等）即可分别获得 27 μg L-1 到 CLO 和 DIAZ。采用 HMDE 的伏安法首先用于测定天然水中的 CLO 和 DIAZ。对天然样品进行加标，回收率测试证实了所开发方法的适用性。对来自巴西巴拉那州的 9 个样品进行了分析，所有样品的 CLO 和 DIAZ 值均低于检测限。