鱼精蛋白-核酸适配体-金纳米技术快速检测牛奶中的卡那霉素

基于聚阳离子鱼精蛋白与带负电的核酸适配体以及金纳米粒子之间的静电作用,发展了一种生物纳米检测技术,用于卡那霉素的检测;优化了缓冲溶液中阳离子、鱼精蛋白以及核酸适配体浓度,结果表明在20 mmol/L Na~+、1 mmol/L Mg~(2+)、2 mg/L鱼精蛋白、100 nmol/L核酸适配体条件下,卡那霉素在5~5 000 nmol/L范围内与金纳米粒子的吸光度比值呈现良好的线性关系,相关系数(R2)为0.992 8,方法的检出限为0.53 nmol/L。在此实验条件下,检测了牛奶中卡那霉素的含量,回收率为96%~98%,相对标准偏差为1.5%~3.2%。该方法选择性高,灵敏度好,线性范围广,显示出其应用于食品中卡那霉素检测的优势。

Fast detection of kanamycin in milk by protamine-aptamer-gold nanotechnology

A bio-nanodetection system was developed for kanamycin based on electrostatic interaction between polycationic protamine and negatively charged aptamer or gold nanoparticles (AuNPs). The concentrations of protamine, aptamer and cations in the buffer solution were optimized. The results showed that there was a good linear correlation (R²=0.9928) between gold nanoparticles and kanamycin in the range of 5-5000 nmol/L with 20 mmol/L Na⁺, 1 mmol/L Mg²⁺, 2 mg/L protamine and 100 nmol/L aptamer. The limit of detection was 0.53 nmol/L. Under this experimental condition, the content of kanamycin in milk was detected, the recoveries were 96%-98%, and the relative standard deviations (RSDs) were 1.5%-3.2%. This method has the advantages of high selectivity, good sensitivity and wide linear range, and is useful in the detection of kanamycin in foods.