Evaluation and Characterization of a Commercial Immunosorbent Cartridge for the Solid-Phase Extraction of Phenylureas from Aqueous Matrices
作者:L. E. Vera-Avila、L. Rangel-Ordonez、R. Covarrubias-Herrera
DOI:10.1093/chromsci/41.9.480
日期:2003.10.1
The behavior and main characteristics of a commercial immunosorbent (IS) cartridge for the solid-phase extraction of phenylureas are determined in this work. The measured capacity for the analyte-antigen (isoproturon) in a new cartridge is 215 ng and, after more than 100 adsorption-desorption cycles, the remaining capacity still is approximately 70 ng, demonstrating the good stability of the bonded antibody and the interesting possibility of extensive cartridge reuse. Only isoproturon and diuron are specifically retained in this sorbent. The weak nonspecific retention of other pesticides, including other phenylureas, can be avoided by increasing the sample volume during the loading step. Thus, a very selective and sensitive method for the determination of isoproturon and diuron in natural and potable waters is developed by loading a 50-mL sample adjusted to pH 7.4 in the IS cartridge, eluting with methanol-water (60:40, v/v), and analyzing the eluate by high-performance liquid chromatography with UV detection. The clean chromatograms, low detection limits (∼ 0.1 µg/L), and good precision (< 5%) obtained with this rapid and simple method demonstrate that immunoaffinity extraction can be an excellent alternative for sample preparation in the environmental monitoring of particular pesticides in water matrices.
本研究确定了用于固相萃取苯脲类化合物的商业免疫吸附剂(IS)柱的行为和主要特性。测量得新柱中分析物-抗原(异丙隆)的容量为215纳克,经过超过100次吸附-解吸循环后,剩余容量仍约为70纳克,展示了结合抗体的良好稳定性以及柱可多次重复使用的潜在可能性。此吸附剂仅特异性地保留异丙隆和敌草隆。其他农药,包括其他苯脲类物质,的非特异性保留可以通过增加加样阶段中的样品体积来避免。因此,通过在IS柱中加载pH 7.4调整的50毫升样品,使用甲醇-水(60:40,体积比)进行洗脱,并通过具有紫外检测的高效液相色谱对洗脱液进行分析,开发了一种用于自然水和饮用水中异丙隆和敌草隆测定的非常选择性和敏感的方法。该快速简单的方法获得的干净色谱图、低检测限(~ 0.1 µg/L)和良好精度(< 5%)表明,免疫亲和萃取可以是水环境中特定农药样品制备的绝佳替代方案。