The NanoBioMedical Centre, Adam Mickiewicz University, Wszechnicy Piastowskiej 3, 61-614 Poznan, Poland.
Department of Biochemistry and Biotechnology, Poznań University of Life Sciences, Dojazd 11, 60-632 Poznan, Poland.
Biosensors (Basel). 2019 Sep 30;9(4):116. doi: 10.3390/bios9040116.
The intensive development and commercialization of genetically modified plants observed over the last decade has led to the development of transgenic detection methods that are rapid and sensitive. Among the strategies used for the detection/monitoring of genetically modified organisms (GMOs), surface plasmon resonance (SPR) meets the necessary criteria. This optical technique measures the changes in the refractive index in the vicinity of thin metal layers (i.e., gold) in response to biomolecular interactions occurring at a flat metal‒solution interface. Additionally, it allows the application of functionalized gold nanoparticles (AuNPs) in SPR research to enhance the signal intensity. In the present study, an SPR method, enhanced by the application of AuNPs, was developed to detect transgenic tobacco plants carrying a antigen. The basis for the detection of the target DNA was the hybridization between the genomic DNA isolated from the leaves, stems, and roots of the transgenic tobacco and the biotinylated oligonucleotide probes immobilized onto a streptavidin (SA) sensor chip. SA-functionalized AuNPs coated with a second type of biotinylated probe were applied to increase the sensitivity of the detection method. Analysis of the results indicated that the constructed SPR-based sensor chip can potentially recognize complementary standard fragments (nonamplified genomic DNA) at concentrations as low as 1 pM. Thus, nonamplified transgenic DNA was detected using a label-free and real-time AuNPs-enhanced SPR biosensing method. This unique approach could be used to detect GMOs with high efficiency, even at a low detection limit, high repeatability, and with less time and a lower cost needed for each analysis.
过去十年中，基因改良植物的密集发展和商业化导致了快速、灵敏的转基因检测方法的发展。在用于检测/监测转基因生物（GMO）的策略中，表面等离子体共振（SPR）符合必要的标准。这种光学技术测量在薄金属层（即金）附近的折射率变化，以响应在平坦金属溶液界面处发生的生物分子相互作用。此外，它允许在 SPR 研究中应用功能化的金纳米颗粒（AuNPs）来增强信号强度。在本研究中，开发了一种通过应用 AuNPs 增强的 SPR 方法来检测携带抗原的转基因烟草植物。检测靶 DNA 的基础是从转基因烟草的叶片、茎和根中分离出的基因组 DNA 与固定在链霉亲和素（SA）传感器芯片上的生物素化寡核苷酸探针之间的杂交。涂有第二种生物素化探针的 SA 功能化 AuNPs 被应用于提高检测方法的灵敏度。对结果的分析表明，所构建的基于 SPR 的传感器芯片有可能以低至 1 pM 的浓度识别互补的标准片段（未扩增的基因组 DNA）。因此，使用无标记和实时 AuNPs 增强的 SPR 生物传感方法检测未扩增的转基因 DNA。这种独特的方法可以以高效率检测 GMO，即使在低检测限、高重复性和每个分析所需的时间和成本较低的情况下也是如此。
