First, two non-complementary strands of phosphate backbone modified oligonucleotides (PM oligo-DNA) were loaded on the surface of the 15 and 25 nm Au nanoparticles, respectively.

• 首先，将两种非互补的磷酸根上硫代修饰的DNA单链分别修饰到15及25纳米金粒子表面。