Department of Physical and Analytical Chemistry, Faculty of Experimental Sciences, University of Jaén, Campus Las Lagunillas , Jaén, Spain.
Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2020 Jun;37(6):983-988. doi: 10.1080/19440049.2020.1740336. Epub 2020 Mar 20.
Rice is one of the most important foods in the world due to its high nutritional value and production. Quinclorac, a selective herbicide, is one of the most detected pesticide residues in rice crops according to pesticide monitoring studies. Common methods for the determination of quinclorac in rice are very time-consuming and labour-intensive, so it is important to develop alternative sensitive and simple analytical methods able to detect quinclorac in food samples. Here we propose a fluorometric method for the screening of this herbicide at excitation/emission wavelengths of 238/358 nm/nm, respectively. A modified QuEChERS method was selected for sample treatment due to its simplicity and high recovery yields. The proposed method presents a detection limit of 2.5 ng mL and satisfactory precision. Recovery experiments were performed in different kinds of rice (white and brown) at or below the Maximum Residue Limit established in European Union (5 mg kg), obtaining values close to 100%. All these characteristics ensure that the proposed method fulfils the requirements for its application in food control.
由于其高营养价值和产量，大米是世界上最重要的食物之一。根据农药监测研究，精喹禾灵是水稻作物中检测到的最常见的农药残留之一。常见的检测大米中精喹禾灵的方法非常耗时耗力，因此开发能够检测食品样品中精喹禾灵的替代灵敏且简单的分析方法非常重要。在这里，我们提出了一种在 238/358nm/nm 的激发/发射波长下筛选该除草剂的荧光方法。由于其简单性和高回收率，选择了改良的 QuEChERS 方法用于样品处理。所提出的方法的检测限为 2.5ng/mL，具有令人满意的精密度。在低于欧盟（5mg/kg）设定的最大残留限量的情况下，在不同种类的大米（白米和糙米）中进行了回收实验，获得了接近 100%的值。所有这些特性都确保了所提出的方法满足其在食品控制中的应用要求。
