Review of computational approaches for predicting the physicochemical and biological properties of nanoparticles

In the growing field of nanotechnology there is a need to determine the physicochemical and potential toxicological properties of nanomaterials since many industrial, medical and consumer applications are based on an understanding of these properties and on a controlled exposure to the materials. This document provides a literature review on the current status of computational studies aimed at predicting the physicochemical properties and biological effects (including toxicity) of nanomaterials, with an emphasis on medical applications. Although a number of models have been published for physicochemical property prediction, very few models have been published for predicting biological effects, toxicity or the underlying mechanisms of action. This is due to two main reasons: a) nanomaterials form a colloidal phase when in contact with biological systems making the definition and calculation of properties (descriptors) suitable for the prediction of toxicity a new and challenging task, and b) nanomaterials form a very heterogeneous class of materials, not only in terms of their chemical composition, but also in terms of size, shape, agglomeration state, and surface reactivity. There is thus an urgent need to extend the traditional structure-activity paradigm to develop methods for predicting the toxicity of nanomaterials, and to make the resulting models readily available. This document concludes by proposing some lines of research to fill the gap in knowledge and predictive methodology. LIST OF ABBREVIATIONS CAS Chemical Abstract Service CDNP Combustion-Derived Nanoparticle CNN Computational Neural Networks CNT Carbon Nanotube CPMD Car-Parrinello Molecular Dynamics DFT Density Functional Theory EINECS European INventory of Existing commercial Chemical Substances EU European Union JRC Joint Research Centre LSER Linear Solvation Energy Relationship LSSVM Least-Squares Support Vector Machine MC Monte Carlo MCDM Multi-Criteria Decision Making MD Molecular Dynamics MI-QSAR Membrane-Interaction Quantitative Structure-Activity Relationship MOT Mobile Order Theory MLR Multilinear Regression MNP Manufactured Nanoparticle NM Nanomaterial NP Nanoparticle OECD Organisation for Economic Co-operation and Development PAH Polycyclic Aromatic Hydrocarbon PE Polyethylene PM Particulate Matter QD Quantum Dot QSAR Quantitative Structure-Activity Relationship REACH Registration, Evaluation, Authorisation and Restriction of Chemicals ROS Reactive Oxygen Species SAR Structure-Activity Relationship SMILES Simplified Molecular Input Line Entry System SVF Synthetic Vitreous Fibres SWNT Single Wall Nanotube