金纳米基比色传感器法测定动物源食品中卡那霉素残留

Kanamycin detecting in animal foods by a gold nanoparticle colorimetric biosensor

基于一定盐浓度下,金纳米粒子的聚集程度受附着于其表面的核酸浓度影响,以及卡那霉素（Kanamycin）能引起核酸适配体特定核酸构象变化而使其脱离金纳米粒子表面的特点,进而引起金纳米粒子颜色变化的结果,设计了一种新型检测动物源食品中卡那霉素的生物传感器。结果表明：此新型传感器对卡那霉素具有较高的灵敏度,且操作简单快速,易于普及和适于现场监控等。当卡那霉素浓度在50~200 nmol/L时,体系的吸光度A650/A519随卡那霉素浓度的变化而呈现线性关系,线性常数为0.999,检测限为30 nmol/L,且在实际样品检测中,测出其回收率为98.27%~104.31%。

Under the certain concentration of NaCl, aggregation of gold nanoparticles is affected by the nucleic acid attaching to its surface. Because of nucleic acid＇ s conformational change by kanamycin, gold nanoparticles color can be changed. Based on this theory, a new type of biosensor has been developed to detect kanamycin in food from animal origin. The results reveal that this new sensor has high sensitivity, and operates quickly and easily. Further- more, it is easy to use and suitable for on-site monitoring. When the concentration of kanamycin is in the range of 50 - 200 nmol/L, the absorption spectrum showed a linear relationship with the change of the kanamycin＇ s concentra- tion, and the linear coefficient was 0. 999. Meanwhile, the optimized method shows a good detection limit （ LOD of 30 nmol/L） , and good recoveries （98.27% - 104.31% ）