This thesis describes the optimisation of the fabrication protocols for vertically-aligned nanostructures to be interfaced with living cells. The dissertation is organised around four aims. The first aim describes the optimisation of a nanoneedle fabrication process. Nanoneedles are regular arrays of conical mesoporous-silicon nanostructures, recently developed by the Stevens Group. The second aim describes one potential novel development for nanoneedles, in the field of biosensing. This involves the selective deposition of silver nanoparticles at the nanoneedle tips, in order to take advantage of Raman-spectroscopy-signal-enhancement phenomena. These were envisioned to facilitate the detection of Raman-active molecules, as well as the investigation of cellular processes. The third aim represents another direction in broadening the horizon of the nanoneedle applications, in the field of cell transfection. This concerns the fabrication of interdigitated, planar electrodes, having nanoneedle-bearing digits. This way, a portable device was envisioned, which could exploit tip-field-enhanced electroporation, as well as tight membrane interface, for improved delivery of molecules to cells. The fourth aim describes the optimisation of the fabrication of nanowires. These were interfaced with bacteria, for prokaryotic-cell transformation purposes. This project is conceptually similar to the nanoneedle-mediated delivery of molecules that has been proven in the literature, but on a smaller scale. Bacteria cells are indeed smaller that eukaryotic ones, thus smaller nanostructures were developed to deliver cargoes into them. This thesis aims to give a contribution to the field of vertically-aligned nanostructures for nanomedicine. This field needs further insights before devices can be used in clinical settings but holds great promises for the future.