The relative chargeability of particles composed of aggregates of nanoparticles by tribocharging was measured and compared with that of conventional particles. Particles were dispersed through a Teflon tribocharger into a 20.8m3 experimental chamber. The net charge-to-mass ratios of the dispersed particles were measured with a Faraday cup charge measuring device. Tribocharging with a Teflon charger was able to charge the particles positively. NanoActive TiO2 gained the greatest net charge-to-mass ratio (1.21mC/kg, s.d.=0.07) followed by NanoActive MgO (0.81mC/kg, s.d.=0.12) and ISO fine test dust (0.66mC/kg, s.d.=0.13). These net charge-to-mass ratios, however, were small compared to the Gaussian limit (8%). Results suggest that commercially available tribochargers may not be suitable for imparting significant charge to nanostructured aggregates.