Tagged molecule induced nanoparticle aggregation： Raman reporter-labeled immuno-Au aggregate as immuno-sensor

<正>A novel structure with high surface enhanced Raman scattering(SERS) activity and bio-specificity as a SERS-based immuno-sensor(named as Raman reporter-labeled immuno-Au aggregate) is demonstrated and employed for protein detection.In each fabrication process,the features of those aggregates are obtained and characterized by ultraviolet-visible(UV-Vis) extinction spectra,transmission electron microscopy (TEM) images,scanning electron microscopy(SEM) pictures,and SERS spectra.Experimental results indicate that proper amounts of the reporter molecules can result in the moderate aggregation morphologies of gold nanoparticles.Compared with the previously reported method using Raman reporterlabeled immuno-Au nanoparticles,more sensitive SERS-based protein detection is realized with this novel immuno-sensor.     

Biocompatible and stable core/shell drug nanocarrier with high surface-enhanced Raman scattering activity

<正>A novel drug carrier based on SiO_2-coated silver nanoparticle aggregates and antitumor drug is successfully synthesized.The surface-enhanced Raman scattering(SERS) spectra of the antitumor drug in living cells are obtained.By using silver nano-aggregates as SERS substrates instead of dispersed silver particles, a great improvement of SERS signal intensity is achieved.It is found that the chemical stability of the drug carrier can also be increased with the existence of SiO_2 shell.The adsorbing effect between antitumor drug 9-aminoacridine(9AA) and silver particles is investigated to optimize the SERS signal. The core/shell structure of the drug carrier is characterized by ultraviolet-visible(UV-Vis) spectroscopy and transmission electron microscopy(TEM) pictures.The experimental results show that the drug carrier offers biocompatibility,stability,and high SERS activity,holding the potential for realizing the intracellular drug tracing.     

基于金纳米聚集体的核壳型SERS探针及其细胞内应用

利用金纳米粒子的聚集体作为表面增强拉曼散射（Surface enhanced Raman scattering,SERS）的增强基底,合成了一种二氧化硅包裹的核壳型SERS探针,并成功将该探针应用于活细胞的SERS光谱探测.实验中利用4-巯基苯甲酸（4-mercaptobenzoicacid,4MBA）作为拉曼标记物,...     

Interaction between antitumor drug and silver nanoparticles: combined fluorscence and surface enhanced Raman scattering study

Optical methods and MTT method are used to characterize the antiproliferation effect of antitumor drug 9-aminoacridine （9AA） with and without silver nanoparticles. Intracellular surface enhanced Raman scattering （SERS） spectra and fluorescent spectra of 9AA indicate the form of 9AA adsorbed on the surface of silver nanoparticles. Although both silver nanoparticles and antitumor drug can inhibit the growth of Hela cells, silver nanoparticles can slow down the antiproliferation effect on Hela cells at low concentration of antitumor drugs. Our experimental results suggest that silver nanoparticles may serve as slow-release drug carriers, which is important in antitumor drug delivery.     

预聚集法制备单层银纳米粒子膜及其SERS活性研究

提出一种预聚集方法来制备单层银纳米粒子膜, 获得了高活性的表面增强拉曼散射基底. 利用紫外-可见吸收光谱、TEM, SEM等表征手段分析了预聚集程度对银纳米单层膜基底SERS活性的影响. 实验发现该方法制备的银纳米粒子膜的SERS活性与预聚集程度直接相关, 在最优参数下制备的SERS基底具有银颗粒分布均匀、SERS活性均一、增强效果好等优点. 实验分别以罗丹明6G (R6G)、3-巯基丙酸(3MPA)和9-氨基吖啶盐酸盐(9AA)为探针对所制备基底的SERS活性进行了测试, 结果均获得了高信噪比的SERS信号.