Au coated Ni nanowires with tuneable dimensions for biomedical applications

Due to their shape anisotropy, high aspect ratio magnetic nanoparticles offer many advantages in biomedical applications. For biocompatibility, it is essential to have full control over the dimensions and surface chemistry of the particles. The aim of this study was to synthesize biocompatible nanowires with tuneable dimensions. This was achieved by electrodeposition of Ni in polycarbonate membranes. To ensure biocompatibility, a continuous gold coating was deposited onto the Ni wires by a newly developed electroless deposition method. The coating was analysed using electron microscopy and X-ray diffraction. Magnetic properties, anisotropy and Au film thickness were studied using vibrating sample magnetometry. After biofunctionalization, no significant cytotoxic effects were found in studies involving a diverse range of primary and tumour cells exposed to increasing concentrations of nanowires for up to 7 days. These nanowires may thus be used for in vivo applications such as magnetic drug delivery.