Electrical signal amplification of DNA hybridization by nanoparticles in a nanoscale gap

We report two different methods to electrically sense deoxyribonucleic acid (DNA) hybridization and suggest that nanoparticles can act as hopping sites that amplify the conductance of the hybridized DNA strand. Single-stranded DNA has no amplification effect on conductance, but hybridized double-stranded DNA tethered to 10nm gold nanoparticles exhibits a 30-fold amplification of conductance. As to the aldehyde-derived target DNA method, silver nanoparticles from silver ion reduction in the 70nm nanogap enhance the conductance signal by 106.