Rossi Liane M, Shi Lifang, Quina Frank H, Rosenzweig Zeev
Langmuir. 2005 May 10;21(10):4277-80. doi: 10.1021/la0504098.
We have developed a simple method to prepare bright and photostable luminescent silica nanoparticles of different sizes and narrow size distribution in high yield. The method is based on the use of Stöber synthesis in the presence of a fluorophore to form bright silica nanoparticles. Unlike micro-emulsion-based methods often used to prepare luminescent silica particles, the Stöber method is a one-pot synthesis that is carried out at room temperature under alkaline conditions in ethanol:water mixtures and avoids the use of potentially toxic organic solvents and surfactants. Our luminescent particles contained the transition metal complex tris(1,10-phenanthroline) ruthenium(II) chloride, [Ru(phen)3]Cl2. They showed higher photostability and a longer fluorescence lifetime compared to free Ru(phen)3 solutions. Leakage of dye molecules from the silica particles was negligible, which was attributed to strong electrostatic attractions between the positively charged ruthenium complex and the negatively charged silica. To demonstrate the utility of the highly luminescent silica nanoparticles in bioassays, we further modified their surface with streptavidin and demonstrated their binding to biotinylated glass slides. The study showed that digital counting of the luminescent nanoparticles could be used as an attractive alternative to detection techniques involving analogue luminescence detection in bioanalytical assays.
我们开发了一种简单的方法，能够高产率地制备出尺寸不同且尺寸分布窄的明亮且光稳定的发光二氧化硅纳米颗粒。该方法基于在荧光团存在的情况下使用施托伯合成法来形成明亮的二氧化硅纳米颗粒。与常用于制备发光二氧化硅颗粒的基于微乳液的方法不同，施托伯法是一种在乙醇与水的混合物中于碱性条件下在室温下进行的一锅法合成，避免了使用潜在有毒的有机溶剂和表面活性剂。我们的发光颗粒含有过渡金属配合物三（1,10 - 菲咯啉）氯化钌（II），[Ru(phen)3]Cl2。与游离的Ru(phen)3溶液相比，它们表现出更高的光稳定性和更长的荧光寿命。染料分子从二氧化硅颗粒中的泄漏可忽略不计，这归因于带正电的钌配合物与带负电的二氧化硅之间的强静电吸引力。为了证明高发光二氧化硅纳米颗粒在生物测定中的实用性，我们用链霉亲和素进一步修饰了它们的表面，并证明了它们与生物素化载玻片的结合。该研究表明，发光纳米颗粒的数字计数可作为生物分析测定中涉及模拟发光检测的检测技术的一种有吸引力的替代方法。
