MINTOTA Research Group, Departament de Química Analítica, Facultat de Química, Universitat de València, Dr. Moliner 50, 46100 Burjassot, Valencia, Spain.
MINTOTA Research Group, Departament de Química Analítica, Facultat de Química, Universitat de València, Dr. Moliner 50, 46100 Burjassot, Valencia, Spain.
Sci Total Environ. 2020 Jun 15;721:137732. doi: 10.1016/j.scitotenv.2020.137732. Epub 2020 Mar 3.
The degradation kinetics and residual levels of the sulfonylurea herbicide tribenuron-methyl (TBM) in different environmental waters were studied using in tube-solid phase microextraction (IT-SPME) coupled on-line to nano-liquid chromatography (nanoLC) and UV diode array detection (DAD). This approach combines the high extraction efficiency of IT-SPME using polymeric coatings reinforced with metal oxide nanoparticles and the high sensitivity attainable by nanoLC, making possible the determination of TBM at low ppb levels (limit of detection, 0.25 ppb) without altering the sample matrix. The present study demonstrated that the preservation of the sample properties is essential to ensure accurate results at these concentration levels due to the high tendency of TBM to hydrolyze, particularly under the acidic conditions involved in most protocols used for sample treatment. The approach used in the present study was applied to evaluate the degradation of this herbicide under different conditions (UV radiation, pH), as well as to study the evolution of its concentration in different environmental waters, namely sea, river, ditch and transition waters. When the samples were exposed to identical conditions, significant differences in the degradation rate of TBM were found depending on the water matrix. The results obtained indicate that this herbicide can persist from several days to weeks depending on the type of water.
采用管内固相微萃取（IT-SPME）与纳升级高效液相色谱（nanoLC）和紫外二极管阵列检测（DAD）联用的方法，研究了磺酰脲类除草剂三甲苯草醚（TBM）在不同环境水中的降解动力学和残留水平。该方法结合了金属氧化物纳米粒子增强聚合物涂层的高萃取效率和 nanoLC 可达到的高灵敏度，可在不改变样品基质的情况下，以低 ppb 水平（检出限为 0.25 ppb）测定 TBM。本研究表明，由于 TBM 水解的趋势很高，特别是在大多数用于样品处理的协议中涉及的酸性条件下，为确保在这些浓度水平下获得准确的结果，保存样品的特性至关重要。本研究中使用的方法用于评估该除草剂在不同条件（UV 辐射、pH 值）下的降解情况，以及研究其在不同环境水中浓度的变化情况，即海水、河水、沟渠和过渡水。当样品暴露于相同的条件下时，TBM 的降解速率因水基质的不同而存在显著差异。结果表明，根据水的类型，这种除草剂可能会持续存在数天到数周。
