Institute of Food Safety and Environment Monitoring, Fuzhou University, Fuzhou, 350108, China.
College of Tourism and Leisure Management, Fujian Business University, Fuzhou, Fujian, 350012, China.
Talanta. 2024 Jan 1;266(Pt 1):124984. doi: 10.1016/j.talanta.2023.124984. Epub 2023 Jul 27.
Okadaic acid (OA) biotoxin acts a well-established inhibitor of protein phosphatase even a tumor promoter of human being, arouse great attention in safety monitoring. However, the powerful and convenient nanosensing technologies for addressing the demands such as rapidity, high sensitivity, and stability in the in-field test of OA shellfish toxin is still scarce. Herein, a high-performance magnetic biometric nanosensor (MBNS) integrating oriented aptamers and ultrasensitive laser-induced fluorescence (LIF) was firstly proposed for the in-field detection of trace OA in seafoods. High-density aptamers hybridized with FAM-labeled cDNA were tethered to the surface of AuNPs on magnetic MIL-101@FeO, and then finely regulated by mercaptohexyl alcohol (MCH) to be orderly assembled, as was successfully utilized to engineer an active biological nanosensor for highly specific recognition of OA. Aptamers anchored on magnetic FeO@MOF@AuNPs activate a biometric microreactor of OA, in which the superior LIF properties, conformation regulation of aptamer, and the specific recognition using aptamer genes were adopted. The magnetic nanosensor with an excellent specificity and super sensitivity for OA analysis was achieved within 20 min. Moreover, the content of captured OA could facilely be recorded by measuring the fluorescence intensity, and the limit of detection (LOD) and limit of quantitation of OA (LOQ) reached 0.015 and 0.050 ng/mL respectively, which was far better than most aptamer-based biometric sensing methods. The feasibility for accurate test of trace OA toxin in the fortified shellfish samples was validated with the recovery yields of 88.2-107.5% and RSD of 0.5-7.6%, respectively. The result demonstrated that the oriented-aptamer encoded MNS had significant practical values in rapid and ultrasensitive detection of OA biotoxin and the related safety applications.
岗田酸（OA）生物毒素是一种有效的蛋白磷酸酶抑制剂，也是人类肿瘤促进剂，在安全监测方面引起了极大关注。然而，在现场测试中，针对 OA 贝类毒素的快速性、高灵敏度和稳定性等需求，仍然缺乏强大而方便的纳米传感技术。在此，本文首次提出了一种高性能磁性生物计量纳米传感器（MBNS），该传感器集成了定向适体和超灵敏激光诱导荧光（LIF），用于现场检测海鲜中的痕量 OA。高密度适体与 FAM 标记的 cDNA 杂交，然后通过巯基己醇（MCH）精细调节，有序组装到磁性 MIL-101@FeO 上的 AuNPs 表面，成功地用于构建高特异性识别 OA 的活性生物纳米传感器。锚定在磁性 FeO@MOF@AuNPs 上的适体激活了 OA 的生物计量微反应体系，其中采用了 LIF 特性、适体构象调节和适体基因的特异性识别。该磁性纳米传感器对 OA 分析具有优异的特异性和超灵敏度，在 20 分钟内即可完成。此外，通过测量荧光强度，可以轻松记录捕获的 OA 含量，OA 的检测限（LOD）和定量限（LOQ）分别达到 0.015 和 0.050 ng/mL，远优于大多数基于适体的生物计量传感方法。该方法在加标贝类样品中痕量 OA 毒素的准确测试中具有可行性，回收率为 88.2-107.5%，RSD 为 0.5-7.6%。结果表明，编码定向适体的 MBNS 在 OA 生物毒素的快速和超灵敏检测及其相关安全应用中具有重要的实用价值。
