Name: Two 5-nm nanogolds bound to 84-base pair double-stranded DNA
Number of unique components: 2
Oligomeric state: Dimer
Details: 5 nm nanogold particles were stabilized via exchanging with bis-(p-sulfonatophenyl) phenylphosphine (BSPP). DNA sequences modified with a 5 thiol moiety were PAGE purified. DNA thiolated at the 5 end was re-suspended in buffer (10mM Tris pH 8, 0.5mM EDTA). Nanogold particles and DNA were combined at a stoichiometric ratio of 1:2 in the presence of a reducing agent. Monoconjugates formed were separated by anion exchange HPLC, and the fractions concentrated by an Amicon Ultra spin filter, MW 100,000 (EMD Millipore Corp, Billerica, MA). Twenty microliters of nanogold monoconjugates, each containing complementary strands of DNA, were combined stoichiometrically as determined by absorption at 520 nm and allowed to react overnight at room temperature. The dimers were purified from unreacted monoconjugates by agarose gel electrophoresis.