Cruz-Vera Marta, Lucena Rafael, Cárdenas Soledad, Valcárcel Miguel
Department of Analytical Chemistry, Campus de Rabanales, University of Cordoba, E-14071 Córdoba, Spain.
J Chromatogr B Analyt Technol Biomed Life Sci. 2007 Oct 1;857(2):275-80. doi: 10.1016/j.jchromb.2007.07.030. Epub 2007 Jul 31.
A continuous-flow configuration based on sequential solid-phase extraction and derivatization is proposed for the screening of urine samples for imipramine and related metabolites. For the first time, a 50/50 (v/v) methanol/nitric acid mixture is used as both eluent and derivatizing reagent. Sample aliquots are injected into the flow manifold and driven by a water stream to an RP-C(18) column where the drugs are quantitatively retained. Following clean-up step with 40/60 (v/v) methanol/water, the eluent/derivatizing reagent is injected and passed through the sorbent column, eluted drugs reacting with nitric acid to form a blue dye that is monitored at 600 nm. The global signal thus obtained for the antidepressants can be used to estimate their total concentration in the samples without the need to individually quantify the analytes. This total index can be used for timely decision-making in case of overdosage. The proposed method is sensitive and selective; thus, typical interferents such as endogenous and diet compounds have no substantial effect on the analytical signal. This allows imipramine and its metabolites to be determined at therapeutic levels in urine samples.
本文提出了一种基于连续固相萃取和衍生化的流动配置方法，用于筛查尿液样本中的丙咪嗪及其相关代谢物。首次使用50/50（v/v）甲醇/硝酸混合物作为洗脱剂和衍生化试剂。将等分试样注入流动系统，由水流驱动至反相C(18)柱，药物在该柱上被定量保留。用40/60（v/v）甲醇/水进行净化步骤后，注入洗脱剂/衍生化试剂并使其通过吸附柱，洗脱的药物与硝酸反应形成蓝色染料，在600 nm处进行监测。由此获得的抗抑郁药的整体信号可用于估计样本中它们的总浓度，而无需单独对分析物进行定量。在过量用药的情况下，这个总指标可用于及时决策。所提出的方法灵敏且具有选择性；因此，内源性和饮食化合物等典型干扰物对分析信号没有实质性影响。这使得在尿液样本中能够测定治疗水平的丙咪嗪及其代谢物。
