DNA-templated fabrication of nickel nanocluster chains

One-dimensional Ni(0) nanocluster chains have been formed on deoxyribonucleic acid (DNA) templates by a multi-step process: activation of DNA by Pd(II), self-organization of Pd(0) nanoparticles on DNA, and deposition of Ni(0) on the Pd(0) on DNA by electroless plating. Immobilization of DNA molecules on a solid support enabled reproducible fabrication of the metallic one-dimensional structures. Analysis of the structures by atomic force microscopy (AFM), UV-vis spectrometry (UVS), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX) revealed that they are microns long, ∼22 nm thick, and made of Ni(0) and Pd(0). Parallel arrays of Ni(0) nanocluster chains have been obtained by metallization of DNA templates oriented by molecular combing. The approach outlined here could be useful in the development of magnetic nanowires.