Nanoparticle collision electrochemistry provides extensive capabilities for detection and characterization of nanoparticles. This presentation will describe development of an electrochemical nano-impact technique for evaluating the fundamental surface properties, functionalization and reactivity of metal and metal oxide nanoparticles and its use for quantifying biomolecule-nanoparticle conjugation and biomolecular recognition with a high degree of sensitivity in the absence of exogenous reagents. The presentation will demonstrate the potential of this method for the: 1) assessment of surface reactivity and electron transfer properties of coated nanoparticles, 2) monitoring surface adsorption/desorption and biorecognition events at single particle surfaces, and 3) as a method enabling rapid label free detection of biomolecular recognition targets. We will demonstrate capabilities of this method as a novel tool for characterizing fundamental properties of nanoparticles, and illustrate novel applications of this method for assessing bioconjugation for biosensing design, analytical and diagnostic applications. Potential advantages and limitations of this approach as a method for the routine study of nanoparticles and nanoparticle systems will also be discussed.