Deliverable Report D4.2 Descriptor Calculation Algorithms and Methods

This deliverable focuses on extensions to the OpenTox descriptor calculation services, in order to account for the supra-molecular pattern (size, shape, porosity and irregularity of the surface area and coatings) governing the activities, effects and properties of ENMs. New descriptors have been derived by applying image analysis techniques on raw microscopy nanomaterial images. The quantummechanical semi-empirical calculation services using the MOPAC open-source software have been adapted and tested on the special requirements of ENM. Experimentally measured compositions of protein coronas (nano-bio interfaces) have been used as fingerprints of ENMs, addressing ENM exposure and life cycle assessment, as well as human and ecological hazard assessment. Further analysis of protein corona data, based on the integration of information form Gene Ontology (GO) resulted in the derivation of GO descriptors. Finally, the popular Java-based Chemistry Development Kit (CDK) has been extended to include nanomaterial descriptors.