粗糙化金纳米颗粒SERS探针用于DNA分子检测

Roughened Au Nanoparticles Based SERS Probes for DNA Detection

采用化学液相还原法,合成了一种新型的表面粗糙化的金纳米颗粒。利用扫描电子显微镜分析了粗糙化金纳米颗粒的形貌特征。进一步,对颗粒生长规律进行了初步探究,发现四氯金酸的浓度对金纳米颗粒的形貌起到重要调控作用。将所制备的金纳米颗粒用于表面增强拉曼光谱(SERS)活性的研究,利用浸泡法形成均匀的金纳米颗粒/DNA分子复合薄膜体系,获得了高质量的SERS图谱。结果表明,粗糙化金纳米颗粒是一种理想的SERS基底,对拉曼活性分子DNA具有良好的SERS效应,这与金纳米结构表面的"热点效应"密切相关。可见,粗糙化金纳米颗粒的SERS探针具有很好的生物分子检测能力,有望扩展到对其他生物分子的拉曼检测。

Surface-roughened Au nanoparticles were synthesized by chemical reduction method.The morphology of the roughened Au nanoparticles was analyzed by scanning electron microscope.Furthermore,the growth mechanism of the Au particles was studied,and it was found that the concentration of HAuCl4 played an important role in regulating the morphology of the particles.The prepared Au nanoparticles were used to study surface-enhanced Raman scattering(SERS)activity.A uniform Au nanoparticles/DNA film was formed by immersion method,and high quality SERS spectra were obtained from this system.The results show that the roughened Au nanoparticles are an ideal SERS substrate for DNA detection because of the"hot spots"on the surface of the Au nanoparticles.The roughened Au nanoparticles as SERS probes have a good ability for biomolecular detection,and are expected to be extended to the Raman study of other biomolecules.