School of Environment and Natural Resources, Renmin University of China, Beijing, 100872, China.
Cell Biochemistry Laboratory, Biology Institute of Hebei Academy of Sciences, Shijiazhuang, 050051, China.
Mikrochim Acta. 2022 May 27;189(6):234. doi: 10.1007/s00604-022-05327-0.
A dual-fluorescence lab-on-fiber biosensor was developed for the rapid and simultaneous on-site determination of acetamiprid and fipronil, based on time-resolved effect and indirect competitive immunoassay principle. The optical fiber modified with two hapten-protein conjugates serves as a bifunctional bio-probe. The dual-color fluorescent reporters were prepared via labeling acetamiprid and fipronil antibodies with Cy5.5 and Alexa Fluor 555, which were excited at 635-nm and 520-nm laser wavelengths, respectively. In the presence of targets, the binding sites of corresponding antibodies were occupied and less antibodies were connected to the probe surface, resulting in the reduction of fluorescence signal. The concentration of acetamiprid and fipronil was determined by measuring the fluorescence signals at 568 nm and 702 nm (emission wavelengths), respectively. Under optimal conditions, the linear response range was 14.2-225.4 ng/L for acetamiprid and 25.1-162.8 ng/L for fipronil, and the limit of detection was 6.51 ng/L and 17.8 ng/L for acetamiprid and fipronil, respectively. The method was successfully applied to the simultaneous detection of acetamiprid and fipronil in three environmental samples, and the recoveries were between 90 and 128%. The dual-fluorescence lab-on-fiber biosensor provides a feasible platform for simultaneous and rapid detection of multiple pesticide residues. A dual-fluorescence lab-on-fiber biosensor was developed for the rapid and simultaneous on-site determination of acetamiprid and fipronil. A bifunctional bio-probe was prepared from the optical fiber modified with two hapten-protein conjugates. Acetamiprid and fipronil antibodies were labeled with different fluorophores and used as dual-color fluorescent reporters.
基于时间分辨效应和间接竞争免疫分析原理，研制了一种用于快速、同时现场测定啶虫脒和氟虫腈的双荧光光纤生物传感器。该光纤经两种半抗原-蛋白质偶联物修饰后作为双功能生物探针。通过用 Cy5.5 和 Alexa Fluor 555 标记啶虫脒和氟虫腈抗体，制备了双荧光报告物，它们分别在 635nm 和 520nm 激光波长下被激发。在存在目标物的情况下，相应抗体的结合位点被占据，与探针表面结合的抗体减少，导致荧光信号减少。通过测量 568nm 和 702nm（发射波长）处的荧光信号，分别确定啶虫脒和氟虫腈的浓度。在最佳条件下，啶虫脒的线性响应范围为 14.2-225.4ng/L，氟虫腈的线性响应范围为 25.1-162.8ng/L，啶虫脒和氟虫腈的检出限分别为 6.51ng/L 和 17.8ng/L。该方法成功应用于三种环境样品中啶虫脒和氟虫腈的同时检测，回收率在 90-128%之间。双荧光光纤生物传感器为同时快速检测多种农药残留提供了一种可行的平台。
