Madkour Engy, Abou Zeid Azza, Abdel Ghany Shaimaa, Alshehrei Fatimah M, El-Ghareeb Doaa, Abdel-Hakeem Mohamed
Department of Pharmaceutical Biotechnology, College of Biotechnology, Misr University for Science and Technology, P. O. Box 77, Giza, Egypt.
Department of Environmental Biotechnology, College of Biotechnology, Misr University for Science and Technology, P. O. Box 77, Giza, Egypt.
Saudi J Biol Sci. 2023 Feb;30(2):103559. doi: 10.1016/j.sjbs.2023.103559. Epub 2023 Jan 18.
protein A () is an important virulence factor that enables to evade host immune responses. The current work aims to detect the gene by a colorimetric method based on gold nanoparticles (AuNPs). For this purpose, the chromosomal DNA of was extracted. Thereafter, primers and thiolated oligonucleotide probe were designed based on protein A sequence data in the gene bank. PCR analysis was performed, and the PCR product was electrophoresed on 2 % agarose gel. Gold nanosensor (Au-Ns) was synthesized by the reaction between AuNPs and the thiolated oligonucleotide probe. The physicochemical properties of AuNPs and Au-Ns were characterized. The detection of the gene was performed based on color change detected by the naked eye and UV-vis spectrophotometry. Finally, the described method was optimized and validated for standard, clinical, and food samples. The PCR analysis showed a characteristic fragment of the gene with a molecular size of 545 base pairs (bp) and a detection limit of 60 pg/ µL. The physicochemical analyses illustrated Au-Ns' correct preparation with a zeta potential of -13.42 mV and particle size range 6-11 nm. Moreover, Au-Ns showed 100 % specificity with a detection limit (DL) of 6 fg/ µL. The proposed method was well described to be applied in clinical and research laboratories.
蛋白A（）是一种重要的毒力因子，可使（此处原文缺失相关信息）逃避宿主免疫反应。当前工作旨在通过基于金纳米颗粒（AuNPs）的比色法检测（此处原文缺失相关基因名称）基因。为此，提取了（此处原文缺失相关菌株名称）的染色体DNA。此后，根据基因库中的蛋白A序列数据设计引物和硫醇化寡核苷酸探针。进行PCR分析，并将PCR产物在2%琼脂糖凝胶上进行电泳。通过AuNPs与硫醇化寡核苷酸探针之间的反应合成金纳米传感器（Au-Ns）。对AuNPs和Au-Ns的理化性质进行了表征。基于肉眼检测到的颜色变化和紫外可见分光光度法对（此处原文缺失相关基因名称）基因进行检测。最后，对所描述的方法针对标准、临床和食品样本进行了优化和验证。PCR分析显示（此处原文缺失相关基因名称）基因的特征性片段，分子大小为545碱基对（bp），检测限为60 pg/μL。理化分析表明Au-Ns制备正确，ζ电位为-13.42 mV，粒径范围为6 - 11 nm。此外，Au-Ns显示出100%的特异性，检测限（DL）为6 fg/μL。所提出的方法被详细描述可应用于临床和研究实验室。
