This is a copy of the slides presented at the meeting but not formally written up for the volume.

Characterization of nanobioparticles is a demanding task. This problem is particularly evident in the case of biomedical applications of nanoparticles where toxicological indices and ADME parameters are the result of complex interactions of the nanoparticle at the molecular, cellular and tissue levels. Furthermore, particles of this size frequently behave in ways that are intrinsically different than those at meso and sub-nano scale. The success of the biological application of nanoparticles depends, however, to a large extent, on our ability to characterize, and eventually predict and control, the properties and behavior of nanoscale particles in realistic biological environments. To help this process, the development of computer-aided nanoparticle characterization approaches is highly desirable. Nanobioparticles include a large array of dissimilar materials under a common name, making the definition of common microscopic criteria matching the modeled molecular properties with the macroscopically observed ones, a daunting task. In this presentation we will review our efforts at devising strategies that, from in-silico simulations of nanoparticles, will help us infer their behavior in complex environments. The approaches presented rely on the application of sensitivity analysis techniques that probe the intrinsic stability of the particle. Particles will be suitable candidates for biological use only if they show low sensitivity to those challenges. The nature of the parameters explored and the possible generalization of this approach will be discussed by presenting our results using metal-loaded fullerenes, gold particles and dendrimers. This work has been funded in part with funds from the NCI-NIH (Contract No. NO1-CO-12400). The contents of this publication do not necessarily reflect the views or policies of the DHHS, nor does mention of trade names, commercial products, or organizations imply endorsement by the U.S. Government.