Ali M R, Bacchu M S, Das S, Akter S, Rahman M M, Saad Aly M Aly, Khan M Z H
Dept. of Chemical Engineering, Jashore University of Science and Technology, Jashore, 7408, Bangladesh; Laboratory of Nano-bio and Advanced Materials Engineering (NAME), Jashore University of Science and Technology, Jashore, 7408, Bangladesh.
Dept. of Microbiology, Jashore University of Science and Technology, Jashore, 7408, Bangladesh.
Talanta. 2023 Feb 1;253:123909. doi: 10.1016/j.talanta.2022.123909. Epub 2022 Sep 6.
An effective tool for early-stage selective detection of the foodborne bacterial pathogen Shigella flexneri (S. flexneri) is essential for diagnosing infectious diseases and controlling outbreaks. Here, a label-free electrochemical DNA biosensor for monitoring S. flexneri is developed. To fabricate the biosensor, detection probe (capture probe) is immobilized on the surface of poly melamine (P-Mel) and poly glutamic acid (PGA), and disuccinimidyl suberate (DSS) functionalized flexible indium tin oxide (ITO) electrode. Anthraquinone-2-sulfonic acid monohydrate sodium salt (AQMS) is used as a signal indicator for the detection of S. flexneri. The proposed DNA biosensor exhibits a wide dynamic range with concentration of the targets ranging from 1 × 10 to 1 × 10 molL with a limit of detection (LOD) of 7.4 × 10 molL in the complementary linear target of S. flexneri, and a detection range of 8 × 10-80 cells/ml with a LOD of 10 cells/ml in real S. flexneri sample. The proposed flexible biosensor provides high specificity for the detection of S. flexneri compared to other target signals such as discrete base mismatches and different bacterial species. The developed biosensor displayed excellent recoveries in detecting S. flexneri in spiked food samples. Therefore, the proposed biosensor can serve as a model methodology for the detection of other pathogens in a broad span of industries.
一种用于食源性病原体福氏志贺菌（S. flexneri）早期选择性检测的有效工具对于诊断传染病和控制疫情至关重要。在此，开发了一种用于监测福氏志贺菌的无标记电化学DNA生物传感器。为制备该生物传感器，将检测探针（捕获探针）固定在聚三聚氰胺（P-Mel）和聚谷氨酸（PGA）以及经二琥珀酰亚胺辛二酸酯（DSS）功能化的柔性氧化铟锡（ITO）电极表面。使用蒽醌-2-磺酸一水合钠盐（AQMS）作为检测福氏志贺菌的信号指示剂。所提出的DNA生物传感器在福氏志贺菌互补线性靶标的浓度范围为1×10至1×10 mol/L时具有较宽的动态范围，检测限（LOD）为7.4×10 mol/L，在实际福氏志贺菌样品中的检测范围为8×10 - 80个细胞/ml，LOD为10个细胞/ml。与其他靶标信号（如离散碱基错配和不同细菌种类）相比，所提出的柔性生物传感器对福氏志贺菌的检测具有高特异性。所开发的生物传感器在检测加标食品样品中的福氏志贺菌时显示出优异的回收率。因此，所提出的生物传感器可作为广泛行业中检测其他病原体的模型方法。
