Fabrication of micro-patterned substrates for plasmonic sensing by piezo-dispensing of colloidal nanoparticles
in: Analytical and Bioanalytical Chemistry (2019)
In this work we describe a very fast and flexible method for fabrication of plasmon supporting substrates with micro-patterning capability. We combined a wet chemistry approach to synthesize metallic nanoparticles with a piezo-dispensing system enabling to deposit the nanoparticles with micrometers precision on the substrates. In this way, arbitrary pattern consisting of 200 micrometer small spots containing plasmonic nanostructures can be produced. Patterns with various nanoparticles exhibiting different plasmonic properties were combined, and the surface density of the particles could be easily varied by their solution concentrations. We showed that under proper conditions the dispensing process caused no aggregation of the particles and it enables full transfer of the colloidal solutions on the substrate. We demonstrated the functionality of such substrates by a detection of small protein adsorption on the spots based on plasmon label-free sensing method.