College of Chemistry and Materials Science, Anhui Key Laboratory of Chemo-Biosensing, Anhui Normal University, Wuhu, People's Republic of China.
Analyst. 2011 Feb 21;136(4):702-7. doi: 10.1039/c0an00583e. Epub 2010 Dec 13.
In this study, we reported a sensitive fluorescent biosensor for detection of DNA hybridization based on Fe/Au core/shell (Fe@Au) nanoparticles (NPs). First, Fe@Au NPs were synthesized using a reverse micelle method, with gold as the shell and iron as the core. The nanoparticle size was confirmed by transmission electron microscopy (TEM). Scanning electron microscopy (SEM) was performed in order to elucidate the morphology of the Fe@Au NPs. Then probe DNA with -SH at the 5'-phosphate end was covalently immobilized onto the surface of the Fe@Au NPs. The DNA hybridization event can be detected by a fluorescent method and methylene blue (MB) as the fluorescent probe. The decline of the fluorescence intensity of MB (ΔF) was linear with the concentration of the complementary DNA from 3.0 × 10(-13) to 1.0 × 10(-9) M with a detection limit of 1.0 × 10(-13) M (S/N = 3). In addition, this approach of DNA detection exhibited excellent selectivity, even for single-mismatched DNA detection.
在这项研究中，我们报道了一种基于 Fe/Au 核/壳（Fe@Au）纳米粒子（NPs）的用于检测 DNA 杂交的灵敏荧光生物传感器。首先，使用反胶束法合成了 Fe@Au NPs，金为壳，铁为核。通过透射电子显微镜（TEM）确认了纳米颗粒的尺寸。进行了扫描电子显微镜（SEM）以阐明 Fe@Au NPs 的形态。然后，将带有 5'-磷酸末端 -SH 的探针 DNA 共价固定在 Fe@Au NPs 的表面上。DNA 杂交事件可以通过荧光法和亚甲蓝（MB）作为荧光探针来检测。MB 的荧光强度下降（ΔF）与互补 DNA 的浓度呈线性关系，从 3.0×10(-13)到 1.0×10(-9) M，检测限为 1.0×10(-13) M（S/N = 3）。此外，这种 DNA 检测方法表现出优异的选择性，甚至可以检测单碱基错配的 DNA。
