Inkjet-Printed Biofunctional Thermo-Plasmonic Interfaces for Patterned Neuromodulation

Abstract

Localized heat generation by the thermo-plasmonic effect of metal nanoparticles has great potential in biomedical engineering research. Precise patterning of the nanoparticles using inkjet printing can enable the application of the thermo-plasmonic effect in a well-controlled way (shape and intensity). However, a universally applicable inkjet printing process that allows good control in patterning and assembly of nanoparticles with good biocompatibility is missing. Here we developed inkjet-printing-based biofunctional thermo-plasmonic interfaces that can modulate biological activities. We found that inkjet printing of plasmonic nanoparticles on a polyelectrolyte layer-by-layer substrate coating enables high-quality, biocompatible thermo-plasmonic interfaces across various substrates (rigid/flexible, hydrophobic/hydrophilic) by induced contact line pinning and electrostatically assisted nanoparticle assembly. We experimentally confirmed that the generated heat from the inkjet-printed thermo-plasmonic patterns can be applied in micrometer resolution over a large area. Lastly, we demonstrated that the patterned thermo-plasmonic effect from the inkjet-printed gold nanorods can selectively modulate neuronal network activities. This inkjet printing process therefore can be a universal method for biofunctional thermo-plasmonic interfaces in various bioengineering applications.

Surface Micro‐ and Nanoengineering: Applications of Layer‐by‐Layer Technology as a Versatile Tool to Control Cellular Behavior

“…C) Gold nanorod (GNR) ink is inkjet printed on the LbL coated substrates in desired patterns, where heat is generated upon near infrared (NIR) illumination. Electrostatic force between oppositely charged gold nanorods and LbL coating is formed to help immobilization and uniform assembly of the nanorods (Adapted with permission . Copyright 2018, American Chemical Society).…”

“…Another strategy is represented in Figure C, where an inkjet printing–based biofunctional thermo‐plasmonic interfaces that can modulate biological activities were developed. They found that inkjet printing of plasmonic nanoparticles on polyelectrolyte LbL substrate coating provides high quality biocompatible thermo‐plasmonic interfaces across different substrates (rigid/flexible, hydrophobic/hydrophilic . W. Chien et al produced LbL multilayer films composed of PAA/PAM with interwoven PAA conjugated with 4‐azidoaniline.…”

Photoactive Organic Substrates for Cell Stimulation: Progress and Perspectives

“…However, inorganic silicon and organic materials remain the predominant active components in optoelectronic devices for cell stimulation. Owing to their localized surface plasmons, metals, in the form of nanoparticles or nanorods, can generate heat due to strong light absorption at certain wavelengths, leading to modulation of neural activities. For inorganic semiconductors, irradiation with photons having energy exceeding the band gap energy can produce electron–hole pairs in the bulk material.…”

Printed 3D Electrode Arrays with Micrometer‐Scale Lateral Resolution for Extracellular Recording of Action Potentials

“…However, cleanroom processing of new MEA designs can be costly or require long development times, which is not ideal for rapid prototyping. Alternative fabrication methods such as additive manufacturing have come to fruition enabling overall lower material waste and faster production times for low‐volume novel designs, using a broad range of different materials . In particular, inkjet technology has become of considerable interest for fabricating MEAs due to its maskless design flexibility and printing capabilities of dielectric and conducting materials .…”