Towards defining new nano-descriptors: extracting morphological features from transmission electron microscopy images

Abstract

Due to the important role of surface-related properties of NPs in their biological behavior, simple and fast methods that could precisely demonstrate accurate information about NPs' surface, structure and morphology are highly desirable. In this study a set of surface morphological nano-descriptors (size, shape, surface area, agglomeration state, curvature, corner count and aspect ratio) have been defined and extracted from Transmission Electron Microscopy (TEM) images of nanoparticles (NPs) by Digital Image Processing methods. The extracted data represent a thorough description of the surface and morphologies of NPs lying beyond their TEM images and can supply the data required for a nano-QSAR approach for predicting toxicity profiles of NPs. These nano-descriptors can provide a framework to further understand the mechanisms which govern the adverse effects of NPs in biological systems. Metallic nanostructures (gold, silver, palladium…) with different sizes (10 to 100 nm), shapes (cube, sphere, rod…) and characteristics were taken into account for which physicochemical indexes were reported. To the best of our knowledge, this is the first ever study that presents numerical values for properties such as shape and agglomeration state which significantly affect NPs behavior.