Direct laser microprinting of hydroxyapatite-clad structures by photoreduction-triggered nanomaterial deposition

Abstract

Hydroxyapatite-based micropatterns were fabricated via near-infrared femtosecond laser irradiation. The micropatterns had a hierarchical cross-section comprising an Ag-based core and an overlying thick layer of non-photosensitive hydroxyapatite nanoparticles. Such micropatterns were continuously formed by the translation of the laser focus in hydroxyapatite nanoparticle-containing AgNO3 solution. A pattern more than quadruple in width was obtained by adding nanoparticles to the solution, despite the same laser irradiation conditions. Raman spectroscopy indicated that the hydroxyapatite nanoparticles retained their crystalline nature even after laser printing. Furthermore, we demonstrate the fabrication of hydroxyapatite-clad patterns on the inner walls of glass capillaries using laser printing.