Zhang Yanyan, Li Wei, Zhang Hao, Wang Shun, Li Xiaodong, Zaigham Abbas Naqvi Syed Muhammad, Hu Jiandong
College of Mechanical and Electrical Engineering, Henan Agricultural University, Zhengzhou, China.
Henan International Joint Laboratory of Laser Technology in Agricultural Sciences, Zhengzhou, China.
Front Chem. 2022 Aug 15;10:965761. doi: 10.3389/fchem.2022.965761. eCollection 2022.
Abscisic acid (ABA) is a plant hormone, which plays an important role in plant growth, crop cultivation and modern agricultural engineering management. Accordingly, the detection of ABA content combined with new techniques and methods has become a more and more popular problem in the field of agricultural engineering. In this work, a SERRS and fluorescence dual-function sensor based on the fluorescence quenching and Raman enhancement properties of gold nanorods (AuNRs) was developed, and applied to the detection of plant hormone ABA. The dual-function reporter molecule Rhodamine isothiocyanate (RBITC) and complementary DNA (cDNA) were modified on AuNRs (AuNRs@RBITC@cDNA) as signal probes and aptamer modified magnetic nanoparticles (FeOMNPs@Apt) as capture probes. Through the specific recognition of ABA aptamer and its complementary chains, an dual-function aptamer sensor based on SERRS and fluorescence was constructed. When ABA molecules were present in the detection system, the signal probes were detached from the capture probes due to the preferential binding between aptamer and ABA molecules. SERS signal of the reporter molecules appeared in the supernatant after magnetic separation, and it increased with the increase of ABA concentration. If the etching agent that can etch AuNRs was added to the supernatant, the AuNRs was etching disappeared, then the signal molecules fall off from the AuNRs, and the fluorescence signal intensity would recovered. The intensity of fluorescence signal also increased with the increase of ABA concentration. Thus, the quantitative relationship between ABA concentration and SERRS intensity and fluorescence intensity of signal molecules was established. The linear range of SERRS detection was 100 fM-0.1 nM, the detection limit was 38 fM; The linear range of fluorescence detection was 1 pM-100 nM, the detection limit is 0.33 p.m. The constructed dual-effect sensor was used in the recovery laboratory of real ABA samples, the recovery rate was up to 85-108%.
脱落酸（ABA）是一种植物激素，在植物生长、作物栽培及现代农业工程管理中发挥着重要作用。因此，结合新技术和方法检测ABA含量已成为农业工程领域一个越来越受关注的问题。在本工作中，基于金纳米棒（AuNRs）的荧光猝灭和拉曼增强特性，开发了一种表面增强共振拉曼散射（SERRS）和荧光双功能传感器，并将其应用于植物激素ABA的检测。将双功能报告分子异硫氰酸罗丹明（RBITC）和互补DNA（cDNA）修饰在AuNRs上（AuNRs@RBITC@cDNA）作为信号探针，将适配体修饰的磁性纳米颗粒（FeOMNPs@Apt）作为捕获探针。通过ABA适配体与其互补链的特异性识别，构建了一种基于SERRS和荧光的双功能适配体传感器。当检测系统中存在ABA分子时，由于适配体与ABA分子之间的优先结合，信号探针从捕获探针上脱离。磁分离后，上清液中出现报告分子的表面增强拉曼散射（SERS）信号，且该信号随ABA浓度的增加而增强。如果向上清液中加入能蚀刻AuNRs的蚀刻剂，AuNRs被蚀刻消失，信号分子从AuNRs上脱落，荧光信号强度将恢复。荧光信号强度也随ABA浓度的增加而增强。由此，建立了ABA浓度与信号分子的SERRS强度和荧光强度之间的定量关系。SERRS检测的线性范围为100 fM - 0.1 nM，检测限为38 fM；荧光检测的线性范围为1 pM - 100 nM，检测限为0.33 pM。所构建的双功能传感器用于实际ABA样品的回收率实验，回收率高达85 - 108%。
