构建下转换荧光-适配体的免疫层析试纸条用于快速检测黄曲霉毒素B1

构建下转换荧光-适配体免疫层析试纸条用于食品中黄曲霉毒素B1（aflatoxin B1，AFB1）的快速高效检测。体系中AFB1存在会减弱下转换荧光-适配体纳米颗粒层析至T线时与AFB1半抗原的结合能力，从而导致下转换荧光信号衰减，进而实现对AFB1的高效检测。该方法在AFB1质量浓度1～40 ng/mL范围内与荧光信号呈良好的线性关系，线性相关系数为0.994，检测限为0.287 ng/mL。该方法利用稀土掺杂荧光纳米颗粒的长寿命发光及近红外荧光特性，有效降低了生物背景荧光干扰并提高了检测体系的特异性。该方法在AFB1的快速高灵敏检测中具有良好的应用前景。

Construction of Down-conversion Fluorescence-Aptamer Immunochromatographic Strip for Rapid Detection of Aflatoxin B1

In this study, a down-conversion fluorescence-aptamer immunochromatographic strip was constructed for the rapid and efficient detection of aflatoxin B1 (AFB1) in foods. The presence of AFB1 in the system will weaken the binding ability of down-conversion-aptamer fluorescent nanoparticles to the hapten AFB1 when down-conversion-aptamer fluorescent nanoparticles reach the T-line, thus leading to the attenuation of down-conversion fluorescence signal and consequently highly efficient detection of AFB1. In the range of 1–40 ng/mL, the concentration of AFB1 had a good linear relationship with the fluorescence signal, showing a correlation coefficient of 0.994, and the detection limit for AFB1 was 0.287 ng/mL. By taking advantage of the long-lived luminescence and the near infrared fluorescence characteristics of rare earth doped fluorescent nanoparticles, this method effectively reduced the interference of biological background fluorescence and improved the specificity of the detection system, making it a promising candidate for application in the rapid and sensitive detection of AFB1.