草甘膦(GlyP)的残留及其主要降解产物,氨甲基膦酸(AMPA),广泛存在于水系统和植物产品中,因此也存在于动物和人类体内。虽然没有确凿的证据,对GlyP癌症风险的担忧持续存在.通常需要测量痕量水平的GlyP和AMPA,但缺乏具有检测灵敏度的现成分析方法。精度和速度。本研究旨在开发一种简单而强大的技术,用于通过流动门控毛细管电泳(CE)对地表水系统中的GlyP和AMPA残基进行灵敏检测。实验上,水样品首先在室温下在低电导率缓冲液中用4-氟-7-硝基苯并呋喃(NBD-F)进行荧光衍生化,并且基于场放大样品注射(FASI)和电动增压(EKS)将混合物注射并浓缩在毛细管中。该方案包括在电渗泵送时注入样品缓冲液的步骤,带负电荷的分析物被电泳拒绝,其次是FASI-EKS的自动电压反转。草铵膦(GluF)的检测灵敏度分别提高了296、444和861倍,AMPA,和GlyP,分别。在准确性方面对所提出的方法进行了验证,精度,检测限(LODs),和线性。LOD估计为50.0pM,5.0pM,而GluF为10.0pM,AMPA,和GlyP,分别。通过测量从当地水系统收集的水样中的GluF和AMPA来证明其应用。本研究为带负电荷的分析物的在线预浓缩提供了一种有效的方法,从而实现对水样中除草剂残留的灵敏检测。该方法也可用于分析其他样品,包括生物流体和植物产品,在适当的样品制备,如分析物的固相萃取。
Residues of glyphosate (GlyP) and its major degradation product, aminomethylphosphonic acid (AMPA), widely exist in the water system and plant products and thus are also present in the bodies of animals and humans. Although no solid evidence has been obtained, the concern about the cancer risk of GlyP is persistent. The measurement of GlyP and AMPA in trace levels is often needed but lacks readily available analytical approaches with detection sensitivity, accuracy and speed. This study aims to develop a simple and robust technique for the sensitive detection of GlyP and AMPA residues in a surface water system with flow-gated capillary electrophoresis (CE). Experimentally, water samples were first fluorogenically derivatized with 4-fluoro-7-nitrobenzofurazan (NBD-F) in a low-conductivity buffer at room temperature, and the mixture was injected and concentrated in the capillary based on field-amplified sample injection (FASI) coupled with electrokinetic supercharging (EKS). This scheme included a step of sample buffer injection upon electroosmotic pumping, where negatively charged analytes were electrophoretically rejected, followed by automatic voltage reversal for FASI-EKS. The detection sensitivity was improved by 296, 444, and 861 times for glufosinate (GluF), AMPA, and GlyP, respectively. The proposed method was validated in terms of accuracy, precision, limits of detection (LODs), and linearity. The LODs were estimated to be 50.0 pM, 5.0 pM, and 10.0 pM for GluF, AMPA, and GlyP, respectively. Its application was demonstrated by measuring GluF and AMPA in water samples collected from a local water system. This study provides an effective approach for the online preconcentration of negatively charged analytes, thus enabling the sensitive detection of herbicide residues in water samples. The method can also be applied to analyze other samples, including biological fluids and plant products, upon appropriate sample preparation such as solid phase extraction of analytes.