Jinru Li

Precise size control of hydrophobic gold nanoparticles using cooperative effect of refluxing ripening and seeding growth

We describe herein a synthetic technology for precise size control of monodispersed hybrid gold nanoparticles, which combines seeding growth and digestive ripening. In this procedure, alkyl amines allow the solubilization and thermal reduction of HAuCl(4) while 2.1xa0nm gold nanoparticles capped by thiol functions are used as seeds. By carefully controlling the HAuCl(4)/seeds ratio, highly monodisperse gold nanoparticles with various sizes (from 2.1 to 8.8xa0nm) can be generated. Variation of the alkyl amines as well as optimization of the growth procedure allows the precise tuning of particle size within a 0.5xa0nm range. On the basis of XPS and TEM studies, a mechanism for nanoparticle formation is proposed.

Formation of polydiacetylene–NH2–gold hollow spheres and their ability in DNA immobilization

A simple and effective means for fabricating gold hollow spheres with controllable gold particle size is presented, where polydiacetylene vesicles terminated with??NH2 were synthesized and used as templates for the fast combination of gold nanoparticles. The combination process of gold to the hollow ball and the subsequent particle reductive growth have been investigated using a quartz crystal microbalance, and the morphology and stability of these hollow spheres are characterized using transmission electron microscopy and ultraviolet?visible spectroscopy. This shows that different sizes of gold particles and a variety of coverage of gold nanoparticles on??NH2-terminated spheres could be easily controlled. The as-prepared gold hollow ball has an excellent ability against mechanical disturbance and the nanogolds on it have very high stability against aggregation and ageing. The immobilization effect of a single-strand DNA probe shows that gold nanoparticles on the surface of this kind of sphere have a great advantage over their counterparts on a planar substrate surface.

Effect of Immobilization Supports on the Amperometric Response of Silver Nanoparticles Enhanced Glucose Oxidase Electrodes

Silver nanoparticles enhanced glucose oxidase electrodes, which are based on polyvinyl butyral and chitosan, were fabricated and investigated. The sensitivity and maximum current i max of the chitosan‐based electrode are 1.06 mA · M−1 and 25.64 µA, respectively. However, the sensitivity and i max of the polyvinyl butyral‐based electrode are 0.34 mA · M−1 and 7.22 µA. The chitosan‐based electrode has a sensitivity 3.1 times higher and a maximum current 3.6 times larger than those of the polyvinyl butyral‐based electrode. Therefore, it is more sensitive and stable than the polyvinyl butyral‐based electrode.