Assembling gold nanoparticle chains using an AC electrical field: Electrical detection of organic thiols

Here we present the utilization of gold nanoparticle (AuNP) chains assembled between two electrodes using an AC electrical field as a potential nanosensor for molecular detection. We describe an easy way to assemble, monitor and characterize the resulting nanoparticle chains electrically. Furthermore, parallelizability and sensing ability of the assembled structures will be addressed. The assembled pearl-chain like structures have the potential to recognize binding events of small molecules with DC current. Bound molecules influencing the charge transfer along the particle chain and therefore generate a signal that can be read electrically. We demonstrate that the produced AuNP-chains can be used for molecular sensing, by measuring the resistances changes due to the interaction with thiols, which are known to bind strongly to gold. The resulting signal was monitored in end-point as well as real-time measurements.