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abstract: 'It is now well accepted that cellular responses to materials in a biological medium reflect greatly the adsorbed biomolecular layer, rather than the material itself. Here, we study by molecular dynamic simulations the competitive protein adsorption on a surface (Vroman effect), i.e. the non-monotonic behavior of the amount of protein adsorbed on a surface in contact with plasma as a function of contact time and plasma concentration. We find a complex behavior, with regimes during which small and large proteins are not necessarily competing between them, but are both competing with others in solution. We show how the effect can be understood, controlled and inverted.'
author:
- Pol Vilaseca
- 'Kenneth A. Dawson'
- Giancarlo Franzese
title: 'Understanding and modulating the competitive surface-adsorption of proteins'
---

Introduction
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When nanoparticles are in contact with blood plasma, or other biological fluids, biomolecules rapidly coat the bare surface in a relatively selective manner [@Ced2007]. It is increasingly accepted that the early biological responses to nanoparticles will be determined by the adsorbed biomolecules rather than the pristine surface alone [@Mono2011; @Kim2012; @Wal2010]. Because of their size [@Mono2011; @Ober2009] nanoparticles are trafficked by active transport processes throughout the organism, using the information 