该研究以四环素类（Tetracyclines，TCs）抗生素的适配体为识别探针，以纳米金为信号传导元件，构建了一种无标记、简便快速的TCs多残留比色检测方法。在优化条件下将其应用于食品中TCs多残留快速检测，并与国标法（GB 31658.6-2021）对比验证。结果显示，样品经甲醇+乙腈（6:4，V/V）提取后采用该方法进行检测，在适配体浓度为150 nmol/L、NaCl浓度40 mmol/L、反应时间5 min等检测条件下，该比色方法对四种TCs的检测线性范围为0.25~5.0 ng/mL（R>0.981），可视化检测限为0.5~1.0 ng/mL，检测时间约5 min。该方法对四环素、土霉素、金霉素和多西环素具有高的特异性，与氯霉素和庆大霉素等无交叉反应。将方法应用于牛乳中TCs检测，加标回收率为63.52%~102.48%，相对标准偏差2.49%~6.81%。结果表明，该方法具有简便、快速、成本低、灵敏度高等优点，适用于批量样品中TCs的现场快速检测。

A label-less, simple, and rapid colorimetric assay for residual tetracyclines (TCs) was developed by combining aptamer probes with gold nanoparticles (AuNPs) as the signal transduction element. This method was used to rapidly detect residual TCs in food under optimal conditions. Additionally, this novel method was then compared to the national standard method for TC residue detection (GB 31658.6-2021). The samples were extracted by methanol and acetonitrile at a 6:4 ratio (V/V) before being assayed using the proposed colorimetric assay. Given an aptamer concentration of 150 nmol/L, NaCl concentration of 40 mmol/L, and reaction time of 5 min, the linear detection range of our colorimetric method for four types of TC was 0.25~5.0 ng/mL (R>0.981). The visual detection limit was 0.5~1.0 ng/mL, and the detection time was approximately 5 min. This method is specific for tetracycline, oxytetracycline, chlortetracycline, and doxycycline, as it has no cross-reactivity for gentamicin and chloramphenicol. Spike recoveries of 63.52%~102.48% and relative standard deviations of 2.49%~6.81% were obtained when detecting TCs in cow’s milk. Therefore, the proposed colorimetric assay is simple, fast, cost efficient, and highly sensitive, which makes it suitable for the rapid batch-screening of TCs in food.

兵团农产品质量安全监管项目（BTNA202203）