Enhancing surface interactions with colon cancer cells on a transferrin-conjugated 3D nanostructured substrate

A transferrin-conjugated PEG-Fe(3) O(4) nanostructured matrix is developed to explore cellular responses in terms of enhanced cell adhesion, specific interactions between ligands in the matrix and molecular receptors on the cell membrane, comparison of cell shapes on 2D and 3D surfaces, and effect of polymer architecture on cell adhesion. Integration of such advanced synthetic nanomaterials into a functionalized 3D matrix to control cell behavior on surfaces will have implications in nanomedicine.

Light-directed nanosynthesis: near-field optical approaches to integration of the top-down and bottom-up fabrication paradigms

The integration of top-down (lithographic) and bottom-up (synthetic chemical) methodologies remains a major goal in nanoscience. At larger length scales, light-directed chemical synthesis, first reported two decades ago, provides a model for this integration, by combining the spatial selectivity of photolithography with the synthetic utility of photochemistry. This review describes attempts to realise a similar integration at the nanoscale, by employing near-field optical probes to initiate selective chemical transformations in regions a few tens of nm in size. A combination of near-field exposure and an ultra-thin resist yields exceptional performance: in self-assembled monolayers, an ultimate resolution of 9 nm (ca. λ/30) has been achieved. A wide range of methodologies, based on monolayers of thiols, silanes and phosphonic acids, and thin films of nanoparticles and polymers, have been developed for use on metal and oxide surfaces, enabling the fabrication of metal nanowires, nanostructured polymers and nanopatterned oligonucleotides and proteins. Recently parallel lithography approaches have demonstrated the capacity to pattern macroscopic areas, and the ability to function under fluid, suggesting exciting possibilities for surface chemistry at the nanoscale.