基于纳米金比色法可视化检测鸡蛋中的氟苯尼考

Visualized detection of florfenicol in eggs by colorimetry based on gold nanoparticles

该研究基于适配体功能化的纳米金构建了比色传感器,在优化各种试验条件的基础上,评估了传感器的灵敏性及特异性,并对鸡蛋中氟苯尼考检测的可行性进行了研究,进而探索将比色传感器与智能手机的成像分析相结合实现快速分析的可行性。比色传感器的优化条件如下:NaCl浓度为50 nmol/L,NaCl孵育时间为5 min,适配体浓度为750 nmol/L,目标物与体系的反应时间为20 min。在此条件下,ΔA;/A;与氟苯尼考(20~40 nmol/L)、氟苯尼考胺的浓度(20~45 nmol/L)均呈现良好线性关系,检测限分别为5.41和6.29 nmol/L,传感器具有良好的特异性。鸡蛋中氟苯尼考及氟苯尼考胺的加标回收率分别为98.65%~103.40%和98.35%~107.49%,相对标准偏差<6.78%。智能手机红蓝绿(red-green-blue, RGB)分析结果发现,蓝红比值的变化量(ΔB/R)与目标物浓度存在线性关系。真实样品检测中,所建立的比色传感器可以有效监测鸡蛋中氟苯尼考含量随给药天数的变化,证实了该方法在实际样品分析应用的可行性。结果表明,传感器实现了鸡蛋中氟苯尼考快速、灵敏、简便的检测,也为其他食品中氟苯尼考残留的检测提供了新的方法与思路。

A colorimetric sensor was developed for the detection of florfenicol(FF) residue based on aptamer modified gold nanoparticles(AuNPs). The test conditions were optimized to improve the sensitivity and stability of the method, and the feasibility of this method for the detection of FF in eggs was also analyzed.In addition, a smartphone was integrated into the colorimetric sensor to eliminate the use of sophisticated equipment and possess the capability for convenient and high-throughput detection. The concentration of NaCl, the incubation time with NaCl, the concentration of aptamers, and the reaction time with target was optimized to be 50 nmol/L, 5 min, 750 nmol/L and 20 min, respectively. The colorimetric sensor displayed linear ranges of detecting florfenicol and florfenicol amine from 20 to 40 nmol/L, and limits of detection(LODs) were 5.41 and 6.29 nmol/L, respectively. The average recoveries of florfenicol and florfenicol amine in egg samples were 98.65%-103.40% and 98.35%-107.49%, with relative standard deviations of less than 6.78%. And from the Red-Green-Blue analysis with the smartphone, the change of Blue/Red value showed linear correlations with the concentration of the target. In real samples detection, this sensor possessed the capability of monitoring the change of florfenicol residue with the extended administration period. The results indicated that this sensor could be a potential tool for the rapid detection of FF residue in food.