Key Laboratory of Sensing Technology and Biomedical Instruments (Guangdong Province), School of Engineering, Sun Yat-Sen University, Guangzhou, People's Republic of China.
Nanotechnology. 2013 Sep 20;24(37):375501. doi: 10.1088/0957-4484/24/37/375501. Epub 2013 Aug 23.
Advances in the controlled assembly of nanoscale building blocks have resulted in functional devices which can find applications in electronics, biomedical imaging, drug delivery etc. In this study, novel covalent nanohybrid materials based upon Ru(bpy)3-doped silica nanoparticles (SiNPs) and gold nanoparticles (AuNPs), which could be conditioned as OFF-ON probes for glutathione (GSH) detection, were designed and assembled in sequence, with the disulfide bonds as the bridging elements. The structural and optical properties of the nanohybrid architectures were characterized using transmission electron microscopy, UV-vis spectroscopy and fluorescence spectroscopy, respectively. Zeta potential measurements, x-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy were employed to monitor the reaction processes of the SiNPs-S-S-COOH and SiNPs-S-S-AuNPs synthesis. It was found that the covalent nanohybrid architectures were fluorescently dark (OFF state), indicating that SiNPs were effectively quenched by AuNPs. The fluorescence of the OFF-ON probe was resumed (ON state) when the bridge of the disulfide bond was cleaved by reducing reagents such as GSH. This work provides a new platform and strategy for GSH detection using covalent nanohybrid materials.
纳米结构单元的可控组装技术的进步已经产生了具有电子、生物医学成像、药物输送等应用的功能器件。在这项研究中，设计并顺序组装了基于Ru(bpy)3-掺杂二氧化硅纳米颗粒（SiNPs）和金纳米颗粒（AuNPs）的新型共价纳米杂化材料，这些材料可以作为谷胱甘肽（GSH）检测的 OFF-ON 探针，其中二硫键作为桥接元素。分别采用透射电子显微镜、紫外可见分光光度法和荧光光谱法对纳米杂化结构的结构和光学性质进行了表征。通过zeta 电位测量、X 射线光电子能谱和傅里叶变换红外光谱监测了 SiNPs-S-S-COOH 和 SiNPs-S-S-AuNPs 合成的反应过程。结果表明，共价纳米杂化结构是荧光暗（OFF 状态）的，表明 AuNPs 有效地猝灭了 SiNPs。当二硫键的桥被 GSH 等还原剂切断时，OFF-ON 探针的荧光恢复（ON 状态）。这项工作为使用共价纳米杂化材料进行 GSH 检测提供了一个新的平台和策略。
