Electrophoretic isolation of discrete Au nanocrystal/DNA conjugates

Colloidal nanocrysta/DNA conjugates hold the promise of becoming powerful probes for biological diagnostics as well as versatile building blocks for nanotechnology. To fully realize this potential, it is important to precisely control the number of oligonucleotides bound to the nanocrystal. Here we demonstrate electrophoretic isolation of 5 and 10 nm gold nanocrystals bearing discrete numbers of single-stranded DNA (1-5). The potential use of these discrete conjugates in the fabrication of novel nanostructures is discussed.