2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/156605We report on the electric measurements of an individual Au nanoparticle with an ultra-high contact resistance of about $10^{19} Ω$. The high-impedance measurements have been carried out by counting the electrons that are transferred onto the particle. In order to do this, a carbon nanotube is used as the electrode for the supply of electrons but also as the detector of the charge transfer. Measurements using single-electron detection allow us to determine the separation between the electron states in the Au nanoparticle, which is about 4 meV, consistent with the charging energy of the particle. Single-electron detection with nanotubes offers great promise for the study of electron transfer in highly resistive molecular systems.4 figuresMesoscale and Nanoscale PhysicsMaterials Sciencetext