Nanomaterials in soils

Soils are complex mixtures of solids from millimeter to nanometer in particle size, which may contain moisture. It is now possible to understand these structures using techniques developed for nanotechnology such as Transmission Electron Microscopy and Atomic Force Microscopy. These techniques illustrate the organisation of colloidal material in soils such as phyllosilicates, and humic acids and the discovery of new particles such as nanoparticles of iron oxides. They show that a micellular host guest supramolecular complex is the correct description for humic material. They show how humic materials restructure and rearrange in response to environmental change such as pH and ionic strength. Nanotechnology offers further potential in identifying single cells, individual DNA molecules. proteins, genes and other biological structures in soils. (c) 2008 Elsevier B.V. All rights reserved