State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
Jiangxi Institute of Veterinary Drug and Feedstuff Control, Nanchang 330047, China.
Biosens Bioelectron. 2017 May 15;91:95-103. doi: 10.1016/j.bios.2016.12.030. Epub 2016 Dec 13.
Label selection is a critical factor for improving the sensitivity of lateral flow assay. Time-resolved fluorescent nanobeads, fluorescent submicrospheres, quantum dots, and colloidal gold-based lateral flow assay (TRFN-LFA, FM-LFA, QD-LFA, and CG-LFA) were first systematically compared for the quantitative detection of ractopamine in swine urine based on competitive format. The limits of detection (LOD) of TRFN-LFA, FM-LFA, QD-LFA, and CG-LFA were 7.2, 14.7, 23.6, and 40.1pg/mL in swine urine samples, respectively. The sensitivity of TRFN-LFA was highest. In the quantitative determination of ractopamine (RAC) in swine urine samples, TRFN-LFA exhibited a wide linear range of 5pg/mL to 2500pg/mL with a reliable coefficient of correlation (R=0.9803). Relatively narrow linear ranges of 10-500pg/mL (FM-LFA) and 25-2500pg/mL (QD-LFA and CG-LFA) were acquired. Approximately 0.005µg of anti-RAC poly antibody (pAb) was used in each TRFN-LFA test strip, whereas 0.02, 0.054, and 0.15µg of pAb were used in each of the FM-LFA, QD-LFA, and CG-LFA test strips, respectively. In addition, TRFN-LFA required the least RAC-BSA antigens and exhibited the shortest detection time compared with the other lateral flow assays. Analysis of the RAC in swine urine samples showed that the result of TRFN-LFA was consistent with that of liquid chromatography-tandem mass spectrometry (LC-MS/MS) and a commercial enzyme-linked immunosorbent assay (ELISA) kit.
标签选择是提高侧向流动分析灵敏度的关键因素。时间分辨荧光纳米珠、荧光亚微米球、量子点和基于胶体金的侧向流动分析（TRFN-LFA、FM-LFA、QD-LFA 和 CG-LFA）首次被系统地比较，用于基于竞争格式的猪尿液中莱克多巴胺的定量检测。在猪尿液样品中，TRFN-LFA、FM-LFA、QD-LFA 和 CG-LFA 的检测限（LOD）分别为 7.2、14.7、23.6 和 40.1pg/mL。TRFN-LFA 的灵敏度最高。在猪尿液样品中莱克多巴胺（RAC）的定量测定中，TRFN-LFA 表现出 5pg/mL 至 2500pg/mL 的宽线性范围，可靠的相关系数（R=0.9803）。获得了相对较窄的线性范围 10-500pg/mL（FM-LFA）和 25-2500pg/mL（QD-LFA 和 CG-LFA）。每个 TRFN-LFA 测试条中使用了约 0.005µg 的抗 RAC 多克隆抗体（pAb），而每个 FM-LFA、QD-LFA 和 CG-LFA 测试条中使用了 0.02、0.054 和 0.15µg 的 pAb。此外，与其他侧向流动分析相比，TRFN-LFA 所需的 RAC-BSA 抗原最少，检测时间最短。对猪尿液样品中 RAC 的分析表明，TRFN-LFA 的结果与液相色谱-串联质谱（LC-MS/MS）和商业酶联免疫吸附测定（ELISA）试剂盒的结果一致。
