Self-assembled films of nanoparticulate TiO2-phytate are prepared on a gold disc-gold disc junction electrode with approximately 6 mu m inter-electrode gap. Charge diffusion dominated by inter-particle hopping of electrons is investigated (in contrast to bulk charge transport) for films immersed in 0.1 M phosphate buffer solution at pH 7 using gold-gold generator-collector voltammetry and chronoamperometry techniques. Numerical simulation based on a basic "randomly propagating" finite difference approach is employed to reveal first approximation potential-dependent apparent diffusion coefficients and apparent concentrations for electrons (D-app increases from 9 x 10(-11) to 18 x 10(-11) m(2) s(-1) and capp increases from 0.2 to 37 M when going from -0.8 to -1.2 V vs. SCE). A mechanistic model for inter-particle versus intra-particle electron hopping is developed. Applications of the inter-particle charge hopping process in electrochemical sensing are suggested. (C) 2012 Elsevier B.V. All rights reserved.