Fabrication of Inkjet-Printed Gold Nanostar Patterns with Photothermal Properties on Paper Substrate

Inkjet printing technology has brought significant advances in patterning
various functional materials that can meet important challenges in personalized medical
treatments. Indeed, patterning of photothermal active anisotropic gold nanoparticles is
particularly promising for the development of low-cost tools for localized photothermal
therapy. In the present work, stable inks containing PEGylated gold nanostars (GNSs)
were prepared and inkjet printed on a pigment-coated paper substrate. A significant
photothermal effect (ΔT ≅ 20 °C) of the printed patterns was observed under near
infrared (NIR) excitation of the localized surface plasmon resonance (LSPR) of the GNS
with low laser intensity (I ≅ 0.2 W/cm2). Besides the pronounced photothermal effect, we
also demonstrated, as an additional valuable effect, the release of a model fluorescent thiolterminated
Bodipy dye (BDP-SH) from the printed gold surface, both under bulk heating
and NIR irradiation. These preliminary results suggest the way of the development of a
new class of low-cost, disposable, and smart devices for localized thermal treatments
combined with temperature-triggered drug release