金纳米粒子组装体的连续离散型纳米结构控制

Preparation of Gold Nanoparticles Assemblies with Controllable,Continuous and Discrete Nanostructures

采用柠檬酸钠还原氯金酸的方法,制备出粒径均一的金纳米粒子(AuNPs),通过加入二水合双(对-磺酰苯基)苯基膦化二钾盐(BSPP),增强了AuNPs体系的分散性与稳定性.选用直径为15和40nm的AuNPs,用不同序列巯基修饰的单链DNA连接到其表面,通过DNA链的杂交,形成不同结构的金纳米粒子组装体.通过改变加入DNA延长连接单元的比例,可以控制金纳米粒子组装体具有连续离散型的1∶1,2∶1和3∶1纳米结构.

Gold nanoparticles （AuNPs） with different sizes （15 and 40 nm） were prepared by reducing chlorauric acid with sodium citrate. The stability of AuNPs was increased when bis（p-sulfonatophenyl）pheny- lphosphine （BSPP） was used as ligand because of its large molecule size and electro-negativity in water. The assemblies of AuNPs were obtained when AuNPs with different particle sizes were conjugated with two thiol- terminated, single-stranded, and complementary DNA （ HS-DNA）, respectively, and hybridized each other. The results indicated that AuNPs assemblies could have controllable, continuous and discrete nanostructures with molar ratios of 1 ： 1,2 ： 1 and 3 ： 1 in the presence of BSPP and with extended strands of DNA as linkers.