Detection of gold nanoparticles based on solid-state nanopore

Gold nanoparticles hold unique optical and electronic properties and have been extensively applied as optical and electrochemical labels for DNA and protein detection. The nanopore based analysis of gold nanoparticles will provide us good insight for further study the conjugation of nanoparticles and DNA. In the present work, we demonstrated gold nanoparticles translocation through silicon nitride (SiN) nanopore via investigation of distribution of current blockage and dwell time of gold nanoparticles with different sizes, 10 nm and 15 nm respectively. 100 mM KCl solution with 0.075% Triton X-100 and 5 mM Tris was used to avoid the aggregation of negatively charged gold nanoparticles caused by van der Waals force. Nanopore based on SiN membrane was fabricated by current dielectric breakdown technology, and the diameter of the nanopore was calculated from an empirical equation, which is 18 nm. Experimental data was analyzed via Clampfit, version 10.6.0.13, and Origin 8 (OriginLab).